WO2013111382A1 - Optical disk device - Google Patents

Optical disk device Download PDF

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Publication number
WO2013111382A1
WO2013111382A1 PCT/JP2012/074615 JP2012074615W WO2013111382A1 WO 2013111382 A1 WO2013111382 A1 WO 2013111382A1 JP 2012074615 W JP2012074615 W JP 2012074615W WO 2013111382 A1 WO2013111382 A1 WO 2013111382A1
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WO
WIPO (PCT)
Prior art keywords
recording
optical disc
signal
layer
spot
Prior art date
Application number
PCT/JP2012/074615
Other languages
French (fr)
Japanese (ja)
Inventor
愼介 尾上
岳 緒方
幸修 田中
鈴木　基之
Original Assignee
日立コンシューマエレクトロニクス株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from JP2012014715A external-priority patent/JP2013157045A/en
Priority claimed from JP2012049918A external-priority patent/JP2013186915A/en
Priority claimed from JP2012066529A external-priority patent/JP2013196754A/en
Application filed by 日立コンシューマエレクトロニクス株式会社 filed Critical 日立コンシューマエレクトロニクス株式会社
Publication of WO2013111382A1 publication Critical patent/WO2013111382A1/en

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    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/08—Disposition or mounting of heads or light sources relatively to record carriers
    • G11B7/09—Disposition or mounting of heads or light sources relatively to record carriers with provision for moving the light beam or focus plane for the purpose of maintaining alignment of the light beam relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following
    • G11B7/094—Methods and circuits for servo offset compensation
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/08—Disposition or mounting of heads or light sources relatively to record carriers
    • G11B7/09—Disposition or mounting of heads or light sources relatively to record carriers with provision for moving the light beam or focus plane for the purpose of maintaining alignment of the light beam relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following
    • G11B7/095—Disposition or mounting of heads or light sources relatively to record carriers with provision for moving the light beam or focus plane for the purpose of maintaining alignment of the light beam relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following specially adapted for discs, e.g. for compensation of eccentricity or wobble
    • G11B7/0956—Disposition or mounting of heads or light sources relatively to record carriers with provision for moving the light beam or focus plane for the purpose of maintaining alignment of the light beam relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following specially adapted for discs, e.g. for compensation of eccentricity or wobble to compensate for tilt, skew, warp or inclination of the disc, i.e. maintain the optical axis at right angles to the disc
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/004—Recording, reproducing or erasing methods; Read, write or erase circuits therefor
    • G11B7/0045—Recording
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/12—Heads, e.g. forming of the optical beam spot or modulation of the optical beam
    • G11B7/135—Means for guiding the beam from the source to the record carrier or from the record carrier to the detector
    • G11B7/1392—Means for controlling the beam wavefront, e.g. for correction of aberration
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
    • G11B7/2403—Layers; Shape, structure or physical properties thereof
    • G11B7/24035—Recording layers
    • G11B7/24038—Multiple laminated recording layers
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/24—Record carriers characterised by shape, structure or physical properties, or by the selection of the material
    • G11B7/2403—Layers; Shape, structure or physical properties thereof
    • G11B7/24047—Substrates
    • G11B7/2405—Substrates being also used as track layers of pre-formatted layers

Definitions

  • the present invention relates to an optical disc apparatus for reproducing information from an optical disc using a laser or recording information on the optical disc.
  • a layer having a physical groove structure (hereinafter referred to as a servo layer) including addresses for addressing and tracking servo control is provided.
  • Patent Document 1 proposes an optical disc composed of a layer (hereinafter referred to as a recording layer) that performs recording and reproduction without a physical groove structure called a groove structure.
  • a recording layer a layer that performs recording and reproduction without a physical groove structure
  • An optical disc in which the recording / reproducing layer does not have a physical groove structure is hereinafter referred to as a grooveless disc.
  • Patent Document 1 states that, “After recording while following the guide track, the tilt state of the disc with respect to the optical axis of the irradiation beam has changed due to warpage due to the change of the disc over time or attachment to the device. When additional recording is performed while following the guide track, a deviation occurs between the recorded recording track and the recording track at the time of additional recording, as shown in FIG.
  • Patent Document 1 states that “the additional recording start position following the recorded area in the recording layer of the guide layer separation type optical recording medium is detected and separated from the additional recording start position to the unrecorded area side at the start of additional recording.
  • the irradiation spot of the first laser beam for servo By moving the irradiation spot of the first laser beam for servo to a position on the guide track opposite to the position, the irradiation spot on the recording layer of the second laser beam for recording or reproduction is moved to follow, and after the movement, “Additional recording on the recording layer is started from the irradiation spot position of the second laser beam”.
  • Patent Document 2 “for tracking using a second spot while irradiating at least a first light spot and a second light spot on a disk-shaped optical recording medium and performing tracking using the first light spot.
  • the technology for forming a mark or a guide groove is disclosed.
  • FIG. 7B shows a case where servo areas 500 aligned in the radial direction are allocated, and a sample servo can be used for tracking.
  • the address information is gray code or CAPA (Complementary Allocated Pit Address). Accordingly, there is a description that the spot interval between the tracks of the first light spot 121 is a half-integer multiple.
  • Patent Document 3 has a problem that “the position accuracy in the radial direction can be improved when a plurality of mark layers are formed in the recording layer of the optical disk”. Then, as a means for solving the problem, “the optical disk apparatus 10 appropriately adjusts the optical paths of the servo light beam LS, the information light beam LM, and the tracking light beam LK in the optical path forming unit 70 of the optical pickup 17, and then the objective lens 18.
  • the servo light beam LS, the information light beam LM, and the tracking light beam LK are condensed respectively, and the optical pickup 17 controls the focus of the objective lens 18 so that the servo light beam LS is focused on the reference layer 104, and By performing tracking control of the objective lens 18 so that the tracking light beam LK is focused on the reference track TE of the target mark layer YG, the focus FM of the information light beam LM condensed by the objective lens 18 is changed to the target mark layer YG. Can be matched to the target track TG " It has been described.
  • the relative position of the light spot irradiated on the recording layer is shifted due to the deviation of the relative angle between the optical disc and the pickup in the radial direction. Due to this relative positional deviation, for example, there is a problem that overwriting of a mark already recorded at the time of additional recording occurs and data is lost.
  • the optical disk recording / reproducing apparatus copes with variations in recording film characteristics and the like for each disk by performing a process called OPC (Optimum Power Power Control) for obtaining the optimum light intensity for recording.
  • OPC Optimum Power Power Control
  • recording is performed while changing the intensity of the laser beam in an OPC area provided on the disk, and a portion is recorded that deviates from the optimum light intensity.
  • Patent Document 1 additional recording is started with a gap from the final recording position of the recorded area. Therefore, the light of each laser beam is caused by warpage due to aging of the optical disk, differences in recording devices, and the like. Even if there is a tilt (tilt) in the optical disc with respect to the axis, overwriting in the recorded area is suppressed.
  • the solution of the above-mentioned Patent Document 1 has a problem that a wasteful area is formed every time additional recording is performed, resulting in a decrease in disk capacity.
  • an object of the present invention is to provide an optical disc apparatus capable of appropriately performing additional recording on a grooveless disc.
  • an optical disc apparatus capable of appropriately performing additional recording on a grooveless disc.
  • FIG. 1 is a block configuration diagram showing an optical disc apparatus of Embodiment 1.
  • FIG. FIG. 2 is a block configuration diagram illustrating a servo error signal generation circuit 104 according to the first embodiment.
  • 1 is a block configuration diagram illustrating a signal processing circuit 105 according to a first embodiment. It is a figure explaining the structure of the optical disk 102, and each laser spot.
  • FIG. 6 is a diagram illustrating the function of a recording layer sub-spot R_SubLS of Example 1.
  • 3 is a flowchart of a setup process according to the first embodiment.
  • 3 is a flowchart of a recording process according to the first embodiment.
  • 7 is a correspondence table showing the operating states of the tracking control system and the focus control system in various operating states and names defined in the present specification.
  • FIG. 6 is a schematic diagram showing a laser spot on a recording layer when performing recording layer SubSpot tracking control according to Example 1; It is a schematic diagram showing a laser spot on the recording layer when the voltage V_TpAdj output from the recording layer track pitch adjustment voltage generation circuit is changed. It is a wave form diagram explaining R_MainTE signal at the time of changing voltage V_TpAdj which a recording layer track pitch adjustment voltage generation circuit outputs. It is a figure explaining the method of calculating the optimal value of the signal of each part in the middle of track pitch adjustment of a present Example, and voltage V_TpAdj. 10 is a flowchart of recording processing according to the second embodiment.
  • FIG. 6 is a configuration diagram showing an optical disk device according to a fifth embodiment.
  • FIG. 6 is a configuration diagram illustrating an optical disc device according to a sixth embodiment Image of change of optical axis due to change of angle of variable angle raising mirror of embodiment 6 Image diagram when the variable angle raising mirror rotates counterclockwise Waveform image diagram of error signal in optical disc apparatus of Examples 5 and 6
  • FIG. 1 is a block diagram showing an embodiment of an optical disc apparatus according to the present invention.
  • the optical disc apparatus 101 records or reproduces information by irradiating an optical disc 102 mounted on the apparatus with laser light, and communicates with a host 114 such as a PC (Personal Computer) through an interface such as SATA (Serial Advanced Technology Attachment). Do.
  • a host 114 such as a PC (Personal Computer) through an interface such as SATA (Serial Advanced Technology Attachment).
  • SATA Serial Advanced Technology Attachment
  • the structure of the optical disk 102 is illustrated in FIG.
  • the optical disk 102 has a servo layer having a track (guide groove) structure and N recording layers (N ⁇ 1, N is a natural number) not having a track structure.
  • a track on the servo layer is referred to as a servo layer track.
  • the pitch (interval) of the servo layer tracks is represented by Tp.
  • Tp The pitch (interval) of the servo layer tracks.
  • Tp The pitch (interval) of the servo layer tracks.
  • S_LB indicates the laser beam irradiated on the servo layer
  • R_LB indicates the laser beam irradiated on the recording layer.
  • the objective lens 1311 generates two laser spots on the recording layer, that is, a recording layer main spot R_MainLS and a recording layer sub-spot R_SubLS. Also, a servo layer laser spot S_LS can be generated for the servo layer.
  • the radial distance between the two laser spots R_MainLS and R_SubLS generated on the recording layer is arranged so as to be substantially equal to the track pitch Tp of the servo layer.
  • FIG. 5 shows the positional relationship between the optical disc 102 and each laser spot when information is additionally recorded on the optical disc 102.
  • FIG. 5 shows a case where information is recorded from the inner periphery toward the outer periphery. That is, a recorded mark row exists in the inner circumferential direction (left direction in FIG. 5) from the recording layer main spot R_MainLS.
  • the mark row formed on the recording layer is hereinafter referred to as a recording layer track in this specification.
  • information is recorded at the recording layer main spot R_MainLS while tracking control is performed using the recording layer sub-spot R_SubLS. Since the distance in the radial direction of R_MainLS and R_SubLS is substantially equal to the track pitch Tp of the servo layer, when information is recorded from the inner circumference to the outer circumference at the recording layer main spot R_MainLS as shown in FIG. By irradiating the recording layer sub-spot R_SubLS on the recording layer track adjacent to this track, the position of the recording layer main spot R_MainLS is controlled at a position on the outer peripheral side by Tp, and information is recorded.
  • the recording layer track irradiated with the recording layer sub-spot R_SubLS is hereinafter referred to as an adjacent recording layer track.
  • the direction perpendicular to the disk surface is the focus direction
  • the disk radial direction is the radial direction
  • the direction perpendicular to the radial direction in the plane parallel to the disk surface is the tangential direction.
  • the optical disk apparatus 101 includes an optical pickup 103, a servo error signal generation circuit 104 that generates various error signals used for servo control, a signal processing circuit 105, a signal processing circuit 106, and a spindle motor for rotating the optical disk 102. 107, a spindle drive circuit 108 that drives the spindle motor 107 according to the rotation signal generated by the spindle drive circuit 108 and generates an FG signal having a frequency corresponding to the rotation speed of the spindle motor 107, and an optical pickup 103.
  • a motor 112 and a slider drive circuit 113 for driving the slider motor 112 are provided.
  • the servo error signal generation circuit 104 includes a recording layer sub tracking error signal generation circuit 1401 that generates a recording layer sub tracking error signal R_SubTE indicating the amount of displacement between the recording layer track and the recording layer sub-spot R_SubLS.
  • a servo layer tracking error signal generation circuit 1403 that generates a servo layer tracking error signal S_TE, and a deviation amount between the recording layer of the optical disc 102 and the focal position of the laser spot R_MainLS.
  • a recording layer focus error signal generation circuit 1404 for generating a recording layer focus error signal R_FE, and a servo layer focus for generating a servo layer focus error signal S_FE indicating a deviation amount between the servo layer of the optical disk 102 and the focal position of the laser spot S_LS.
  • An error signal generation circuit 1405 is provided. Each error signal is output with reference to the potential Vref.
  • the signal processing circuit 105 is a circuit that performs various types of signal processing of the optical disc apparatus, and operates with the potential Vref as a reference.
  • the signal processing circuit 105 includes a system control circuit 1501, A recording layer focus control circuit 1502 that generates a signal for driving the objective lens 1311 in the focus direction according to the R_FE signal, a switch 1503 that switches the output of the recording layer focus control circuit 1502 based on the R_FON signal, and the objective lens 1311
  • Recording layer focus driving voltage generation circuit 1504 for generating a voltage for driving the image in the focusing direction, and an adder for adding the output signal of the switch 1503 and the output signal of the recording layer focus driving voltage generation circuit 1504 to output as an R_FOD signal 1505
  • a servo layer focus control circuit 1506 that generates a signal for driving the relay lens 1321 in the focus direction according to the S_FE signal, a switch 1507 that switches the output of the servo
  • a switch 1517 that switches the output of the recording layer tracking control circuit 1516 based on the R_TON signal and outputs it as an R_TRD signal, and a selector that selects and outputs either the R_TRD signal or the S_TRD signal based on the OL_TSEL signal.
  • a tracking drive voltage generation circuit 1519 that generates a voltage for driving the objective lens 1311 in the radial direction, and the output signal of the selector 1518 and the output signal of the tracking drive voltage generation circuit 1519 are added to form an OL_TRD signal.
  • An adder 1520 that outputs as A recording layer MainTE signal monitor circuit 1523 that monitors the R_Main signal, a slider control circuit 1521 that generates a signal for moving the slider motor 112, and a spindle control circuit 1522 that generates a rotation signal for rotating the spindle motor 107. I have.
  • the optical pickup 103 performs servo control on the servo layer, and also stores data in a servo layer optical system for reproducing an address corresponding to a position on the disk and information unique to the disk, and a plurality of recording layers at different distances from the servo layer. Is composed of a recording layer optical system for recording / reproducing data.
  • the laser power control circuit 1301 is controlled by the system control circuit 1501 and outputs a current for driving the laser diode 1302. This driving current is applied with high frequency superposition of several hundred MHz in order to suppress laser noise.
  • the laser diode 1302 emits a laser beam R_LB having a wavelength of 405 nm, for example, with a waveform corresponding to the drive current.
  • the emitted laser light is converted into parallel light by the collimator lens 1303, partly reflected by the beam splitter 1304, and condensed on the power monitor 1306 by the condenser lens 1305.
  • the power monitor 1306 feeds back a current or voltage corresponding to the intensity of the laser light to the system control circuit 1501 as an R_PM signal.
  • the intensity of the laser beam R_LB focused on the recording layer of the optical disc 102 is maintained at a desired value such as 2 mW.
  • the laser beam R_LB that has passed through the beam splitter 1304 is reflected by the polarization beam splitter 1307, and the convergence and divergence are controlled by the spherical aberration correction element 1309 driven by the aberration correction element drive circuit 111, and transmitted through the dichroic mirror 1308.
  • the dichroic mirror 1308 is an optical element that reflects light of a specific wavelength and transmits light of other wavelengths.
  • the laser beam R_LB that has passed through the dichroic mirror 1308 becomes circularly polarized light by the quarter-wave plate 1310 and is condensed as a laser spot R_MainLS on the recording layer of the optical disc 102 by the objective lens 1311. Further, as described with reference to FIG. 4, the recording layer sub-spot R_SubLS is condensed at a position separated from the recording layer main spot R_MainLS by the track pitch Tp of the servo layer in the radial direction.
  • the spherical aberration correction element 1309 is controlled from the system control circuit 1501 via the aberration correction element driving circuit 111 so as to be at a predetermined position corresponding to the recording layer of the grooveless disk.
  • the intensity of the laser beam R_LB reflected by the optical disc 102 is modulated according to information recorded on the optical disc 102.
  • the light is linearly polarized by the quarter-wave plate 1310, passes through the dichroic mirror 1308, and passes through the polarization beam splitter 1307 and the spherical aberration correction element 1309.
  • the transmitted laser beam R_LB is condensed on the detector 1314 and the detector 1324 by the condenser lens 1313.
  • the detector 1314 and the detector 1324 detect the intensity of the laser beam R_LB and output a signal corresponding to the detected intensity. At this time, the detector 1314 detects the intensity of the light reflected at the recording layer main spot R_MainLS, and the detector 1324 detects the intensity of the light reflected at the recording layer sub-spot R_SubLS.
  • the output signal of the detector 1314 is output to the servo error signal generation circuit 104 and the reproduction signal generation circuit 106, and the output signal of the detector 1324 is output to the servo error signal generation circuit 104.
  • a recording layer focus error signal generation circuit 1404 indicates a recording layer focus error signal indicating the amount of deviation between the recording layer of the optical disc 102 and the focal position of the laser spot R_MainLS from the signal output from the detector 1314.
  • R_FE is generated.
  • the signal output from the detector 1314 is also input to the recording layer main tracking error signal generation circuit 1402 to generate a recording layer main tracking error signal R_MainTE indicating the amount of displacement between the recording layer track and the recording layer main spot R_MainLS.
  • the signal output from the detector 1324 is input to the recording layer sub tracking error signal generation circuit 1401 to generate a recording layer sub tracking error signal R_SubTE indicating the amount of displacement between the recording layer track and the recording layer sub-spot R_SubLS.
  • the error signal generated by the servo error signal generation circuit 104 is input to the signal processing circuit 105, and focus control and tracking control for the recording layer are performed.
  • the recording layer focus control circuit 1502 performs gain and phase compensation for the recording layer focus error signal R_FE in response to a command signal from the system control circuit 1501, and outputs a drive signal for performing focus control on the recording layer.
  • the drive signal output from the recording layer focus control circuit 1502 is input to the actuator drive circuit 109 via the switch 1503 and the adder 1505.
  • the switch 1503 selects and outputs the output signal of the recording layer focus control circuit 1502 or the reference potential Vref based on the R_FON signal output from the system control circuit 1501.
  • the switch 1503 selects the terminal a, and the output signal of the recording layer focus control circuit 1502 is output to the actuator drive circuit 109 via the adder 1505.
  • the switch 1503 selects the terminal b and outputs the reference potential Vref.
  • the R_FON signal is a signal for instructing on / off of focus control for the recording layer.
  • the switch 1503 functions as a switch for switching on / off the focus control for the recording layer.
  • the focus control for the recording layer is turned on, and this operation is called a focus pull-in operation.
  • the recording layer focus drive voltage generation circuit 1504 outputs a predetermined voltage in response to a command signal from the system control circuit 1501.
  • the recording layer focus drive voltage generation circuit 1504 outputs, for example, a sweep voltage in the focus sweep operation and a jump voltage at the time of focus jump.
  • a general CPU can be used as the recording layer focus drive voltage generation circuit 1504.
  • the adder 1505 adds the output signal of the switch 1503 and the output signal of the recording layer focus drive voltage generation circuit 1504, and outputs the result to the actuator drive circuit 109 as the recording layer focus drive signal R_FOD.
  • Actuator drive circuit 109 drives actuator 1312 configured to operate integrally with objective lens 1311 in a direction perpendicular to the disk surface in accordance with recording layer focus drive signal R_FOD.
  • the actuator drive circuit 109 drives the actuator 1312 according to the recording layer focus drive signal R_FOD to displace the position of the objective lens 1311 in the focus direction, and the recording layer focus servo control so that the laser beam R_LB is focused on the recording layer. I do.
  • this control is called recording layer focus control.
  • the recording layer tracking control circuit 1516 performs gain and phase compensation for the recording layer tracking error signal R_TE according to a command signal from the system control circuit 1501, and outputs a drive signal for performing tracking control on the recording layer.
  • the drive signal output from the recording layer tracking control circuit 1516 is input to the actuator drive circuit 109 via the switch 1517, the selector 1518, and the adder 1520.
  • the recording layer tracking error signal R_TE input to the recording layer tracking control circuit 1516 is either an R_Sub signal or an R_Main signal, and the selector 1513 performs signal selection based on the R_TESEL signal from the system control circuit 1501. Is called.
  • the selector 1513 selects the terminal g and outputs the R_Sub signal.
  • the selector 1513 selects the terminal h and outputs the R_Main signal. To do.
  • the recording layer tracking error signal R_TE selected by the selector 1513 is added to the signal R_TpAdj output from the recording layer track pitch adjustment voltage generation circuit 1514 by the adder 1515 and then input to the recording layer tracking control circuit 1516.
  • the recording layer track pitch adjustment voltage generation circuit 1514 outputs a predetermined voltage as the R_TpAdj signal.
  • the voltage of the R_TpAdj signal is represented by V_TpAdj.
  • the switch 1517 selects the output signal of the recording layer tracking control circuit 1516 or the reference potential Vref based on the R_TON signal output from the system control circuit 1501, and outputs it as the recording layer tracking drive signal R_TRD.
  • the switch 1517 selects the terminal i, and the output signal of the recording layer tracking control circuit 1516 is output to the actuator drive circuit 109.
  • the switch 1517 selects the terminal j and outputs the reference potential Vref.
  • the R_TON signal is a signal for instructing on / off of tracking control for the recording layer.
  • the switch 1517 functions as a switch for switching on / off the tracking control for the recording layer.
  • tracking control for the recording layer is turned on, and this operation is called a track pull-in operation.
  • the recording layer tracking drive signal R_TRD output from the switch 1517 is input to the selector 1518.
  • the selector 1518 selects and outputs either the R_TRD signal or the S_TRD signal described later based on the OL_TSEL signal output from the system control circuit 1501. Here, since the recording layer optical system is described, it is assumed that the selector 1518 outputs an R_TRD signal.
  • the tracking drive voltage generation circuit 1519 outputs a predetermined voltage in response to a command signal from the system control circuit 1501. For example, the tracking drive voltage generation circuit 1519 outputs a jump voltage at the time of track jump.
  • the tracking drive voltage generation circuit 1519 also receives an FG signal output from the spindle drive circuit 108, and outputs a jump voltage at the time of track jump in synchronization with the rotation of the optical disk 101 using the FG signal. An operation of continuing to follow the same track 101 can also be performed.
  • a general CPU can be used as the tracking drive voltage generation circuit 1519.
  • the adder 1520 adds the output signal of the selector 1518 and the output signal of the tracking drive voltage generation circuit 1519 and outputs the result to the actuator drive circuit 109 as an objective lens drive tracking drive signal OL_TRD.
  • the actuator drive circuit 109 drives the actuator 1312 in the radial direction according to the objective lens drive tracking drive signal OL_TRD, thereby displacing the position of the objective lens 1311 and irradiating the laser spot on the recording layer track or the servo layer track. Tracking control.
  • the actuator drive circuit 109 in this embodiment includes a circuit that drives in the focus direction and a circuit that drives in the tracking direction.
  • control in the case of using R_SubTE as the R_TE signal is hereinafter referred to as recording layer SubSpot tracking control.
  • control in the case of using R_MainTE as the R_TE signal is hereinafter referred to as recording layer MainSpot tracking control.
  • the laser power control circuit 1301 is controlled by the system control circuit 1501 and outputs a current for driving the laser diode 1315.
  • the laser diode 1315 emits laser light S_LB having a wavelength of 650 nm, for example.
  • Part of the laser light S_LB passes through a collimator lens 1316, a beam splitter 1317, and a condenser lens 1318, and the power is monitored by a power monitor 1319.
  • the intensity of the laser light S_LB focused on the servo layer of the optical disc 102 is maintained at a desired power such as 3 mW.
  • the laser beam S_LB that has passed through the beam splitter 1317 passes through the polarization beam splitter 1320, and is controlled to converge and diverge by the relay lens 1321.
  • the laser beam S_LB that has passed through the relay lens 1321 is reflected by the dichroic mirror 1308, passes through the quarter-wave plate 1310, and is condensed as a laser spot S_LS on the servo layer of the optical disc 102 by the objective lens 1311.
  • the laser beam S_LB reflected by the optical disk 102 is reflected by the polarization beam splitter 1320 and condensed on the detector 1323 by the condenser lens 1322.
  • the detector 1323 detects the intensity of the laser beam and outputs a signal corresponding to the intensity to the signal processing circuit 106.
  • the signal processing circuit 106 is a synchronization signal for controlling the rotation of the optical disc 102 based on a signal corresponding to a track formed by wobbling the servo layer output from the detector 1323, and a clock used as a reference for recording or reproduction. A signal is generated, and an address corresponding to the position on the disc that the laser spot S_LS is following is reproduced and output to the system control circuit 1501.
  • a servo layer focus error signal generation circuit 1404 indicates a servo layer focus error signal indicating an amount of deviation between the servo layer of the optical disc 102 and the focal position of the laser spot S_LS from the signal output from the detector 1323.
  • S_FE is generated.
  • the signal output from the detector 1323 is also input to the servo layer tracking error signal generation circuit 1402 to generate a servo layer tracking error signal S_TE indicating the amount of displacement between the servo layer track and the laser spot S_LS.
  • the error signal generated by the servo error signal generation circuit 104 is input to the signal processing circuit 105, and focus control and tracking control for the servo layer are performed.
  • Servo layer focus control circuit 1506 performs gain and phase compensation for servo layer focus error signal S_FE in response to a command signal from system control circuit 1501, and outputs a drive signal for performing focus control on the servo layer.
  • the drive signal output from the servo layer focus control circuit 1506 is input to the relay lens drive circuit 110 via the switch 1507 and the adder 1509.
  • the switch 1507 selects and outputs the output signal of the servo layer focus control circuit 1506 or the reference potential Vref based on the S_FON signal output from the system control circuit 1501.
  • the switch 1507 selects the terminal c, and the output signal of the servo layer focus control circuit 1506 is output to the relay lens driving circuit 110 via the adder 1509.
  • the switch 1507 selects the terminal d and outputs the reference potential Vref.
  • the S_FON signal is a signal for instructing on / off of focus control for the servo layer.
  • the switch 1507 functions as a switch for switching on and off the focus control for the servo layer.
  • the focus control for the servo layer is turned on, and this operation is called a focus pull-in operation.
  • Servo layer focus drive voltage generation circuit 1508 outputs a predetermined voltage in response to a command signal from system control circuit 1501.
  • the servo layer focus drive voltage generation circuit 1508 outputs, for example, a sweep voltage in the focus sweep operation and a jump voltage at the time of focus jump.
  • a general CPU can be used as the servo layer focus drive voltage generation circuit 1508, for example, a general CPU can be used.
  • the adder 1509 adds the output signal of the switch 1507 and the output signal of the servo layer focus drive voltage generation circuit 1508, and outputs the result to the relay lens drive circuit 110 as the servo layer focus drive signal S_FOD.
  • the relay lens drive circuit 110 drives the relay lens 1321 according to the servo layer focus drive signal S_FOD, thereby displacing the focal position of the laser light S_LB in the focus direction, and focus control so that the laser light S_LB is focused on the servo layer. I do. In this specification, this control is called servo layer focus control.
  • Servo layer tracking control circuit 1510 performs gain and phase compensation for servo layer tracking error signal S_TE in response to a command signal from system control circuit 1501, and outputs a drive signal for performing tracking control on the recording layer.
  • the drive signal output from the servo layer tracking control circuit 1510 is input to the actuator drive circuit 109 via the switch 1511, the selector 1518, and the adder 1520, and simultaneously input to the relay lens drive circuit 110 via the switch 1511 and the selector 1517. Is done.
  • the switch 1511 selects the output signal of the servo layer tracking control circuit 1510 or the reference potential Vref based on the S_TON signal output from the system control circuit 1501, and outputs it as the servo layer tracking drive signal S_TRD.
  • the switch 1511 selects the terminal i, and the output signal of the servo layer tracking control circuit 1510 is output.
  • the switch 1511 selects the terminal j and outputs the reference potential Vref.
  • the S_TON signal is a signal for instructing on / off of tracking control for the servo layer.
  • the switch 1511 functions as a switch for switching on / off of tracking control for the servo layer.
  • tracking control for the servo layer is turned on, and this operation is called a track pull-in operation.
  • Servo layer tracking drive signal S_TRD output from switch 1511 is input to selector 1518 and selector 1512.
  • the selector 1518 selects either the R_TRD signal or the S_TRD signal based on the OL_TSEL signal output from the system control circuit 1501 and outputs it as the objective lens drive tracking drive signal OL_TRD.
  • the selector 1518 selects the terminal k and outputs the R_TRD signal.
  • the selector 1518 selects the terminal l and outputs the S_TRD signal. To do.
  • the selector 1512 selects either the S_TRD signal or the reference potential Vref based on the RL_TSEL signal output from the system control circuit 1501 and outputs it as the relay lens drive tracking drive signal RL_TRD.
  • the selector 1512 selects the terminal g and outputs the S_TRD signal.
  • the selector 1512 selects the terminal h and sets the reference potential Vref. Output.
  • the relay lens drive circuit 110 drives the relay lens 1321 in accordance with the tracking drive signal RL_TRD, thereby displacing the focal position of the laser light S_LB in the radial direction and performing tracking control so that the laser spot is irradiated onto the servo layer track.
  • the relay lens driving circuit 110 in this embodiment includes a circuit for driving the focal position of the laser light S_LB in the focus direction and a circuit for driving in the tracking direction.
  • the servo layer tracking drive signal S_TRD is input to the actuator drive circuit 109 or the relay lens drive circuit 110 by the RL_TSEL signal and the OL_TSEL signal. Also, it is assumed that they are not input to both at the same time. In other words, the tracking control for the servo layer in the optical disc apparatus 101 of this embodiment can be switched between a circuit configuration for driving the actuator 1312 and a circuit configuration for driving the relay lens 1321.
  • the control performed by driving the actuator 1312 is hereinafter referred to as objective lens driving servo layer tracking control.
  • the control in the case where the relay lens 1321 is driven is hereinafter referred to as relay lens driving servo layer tracking control.
  • Control performed when the actuator 1312 is driven is hereinafter referred to as relay lens drive servo layer tracking control.
  • the slider control circuit 1521 outputs a slider drive signal SLD for driving the slider motor 112 based on the average value of the output signals of the selector 1518 in response to a command signal from the system control circuit 1501.
  • the slider motor 112 is driven by the slider drive circuit 113 in accordance with this SLD signal, and the optical pickup 103 is moved in the disk radial direction so that the actuator 1312 operates in the vicinity of the center position of the movable range in the disk radial direction.
  • the operation of the signal processing circuit 106 will be described.
  • tracking servo control is performed so that the laser spot S_MainLS follows the servo layer track.
  • a reproduction signal from the servo layer is output from the detector 1323 and input to the signal processing circuit 106.
  • data to be recorded on the recording layer input from the host 114 and address information corresponding to the position on the disk where the data is recorded are output from the system control circuit 1501 to the signal processing circuit 106.
  • the signal processing circuit 106 modulates the input data and address information by a predetermined method based on the reference clock signal reproduced from the servo layer, and outputs it to the laser power control circuit 1301.
  • the laser power control circuit 1301 outputs a drive current corresponding to the output of the signal processing circuit 106 to the laser diode 1302, and the laser diode 1302 emits the laser beam R_LB with a corresponding intensity, so that recording is performed on the recording layer of the optical disc 102. Is called.
  • recording is performed on the recording layer while following the tracks formed on the guide layer, so that information is recorded on the recording layer along the same locus as the spiral of the track of the guide layer.
  • the guide layer track is formed in a spiral shape from the inner periphery to the outer periphery
  • the track recorded by the recording layer is formed in a spiral shape from the inner periphery to the outer periphery in the same manner. .
  • tracking servo control is performed so that the laser spot R_MainLS follows a track formed by the locus of information recorded on the recording layer.
  • a reproduction signal from the recording layer is output from the detector 1314 and input to the signal processing circuit 106.
  • the signal processing circuit 106 generates a synchronization signal for controlling the rotation of the optical disc 102 and a clock signal serving as a reference for reproduction from the input reproduction signal.
  • the signal processing circuit 106 performs processing such as amplification, equalization, and decoding on the reproduction signal, and outputs the decoded data and address information corresponding to the position of the data on the disk to the system control circuit 1501.
  • the system control circuit 1501 outputs the reproduced data to the host 114.
  • the synchronization signal output from the signal processing circuit 106 and the FG signal output from the spindle driving means 108 are input to the spindle control circuit 1522.
  • the spindle control circuit 1522 outputs a spindle drive signal SPD based on an FG signal having a frequency corresponding to the rotation speed of the spindle motor 107 when the optical disk 102 is rotated at a constant angular speed according to a command signal from the system control circuit 1501.
  • a spindle drive signal SPD based on a synchronization signal reproduced from the servo layer or the recording layer is output.
  • the spindle drive circuit 108 performs spindle control so that the rotational speed of the optical disk becomes a predetermined value by driving the spindle motor 107 in accordance with the SPD signal.
  • FIG. 6 shows a flowchart of the setup process when the optical disc 102 is inserted into the optical disc apparatus 101 of the present embodiment.
  • a setup process is started (step S601).
  • the optical disk apparatus first performs a disk recognition process (step S602).
  • the disc recognition process the presence / absence of the disc and the disc type are confirmed.
  • the system control circuit 1301 instructs the laser power control circuit 1301 to cause one of the laser diodes to emit light, and at the same time, the system control circuit 1301 instructs the recording layer focus drive voltage generation circuit 1504 to objective lens 1311.
  • the system control circuit 1301 instructs the laser power control circuit 1301 to cause one of the laser diodes to emit light
  • the system control circuit 1301 instructs the recording layer focus drive voltage generation circuit 1504 to objective lens 1311.
  • reflected light is detected by any detector, and recognition can be performed using the detected signal.
  • the optical disc apparatus performs an aberration correction element driving process (step S603). This is preparation for a focus pull-in process, which will be described later, and the aberration correction element 1309 is driven so that a predetermined aberration correction amount is obtained.
  • the optical disc apparatus performs a relay lens driving process (step S604). This is preparation for a focus pull-in process described later, and the relay lens 1321 is driven so that the position of the relay lens becomes a predetermined position.
  • step S604 focus pull-in processing is performed on the recording layer of the optical disc 101 (step S605).
  • the system control circuit 1301 instructs the recording layer focus drive voltage generation circuit 1504 to output a voltage having a predetermined pattern, and changes the R_FON signal from Low level to High level.
  • An actuator 1312 configured to operate integrally with the objective lens 1311 is driven by the recording layer focus drive voltage generation circuit 1504 in a direction perpendicular to the disk surface, and the switch 1311 is switched by changing the level of the R_FON signal to control the recording layer focus. Is turned on.
  • step S606 focus pull-in processing is performed on the servo layer of the optical disc 101 (step S606).
  • the system control circuit 1301 instructs the servo layer focus drive voltage generation circuit 1508 to output a predetermined pattern voltage, and changes the S_FON signal from the Low level to the High level.
  • the relay lens 1311 is driven by the servo layer focus drive voltage generation circuit 1508 to displace the focus position of the laser light S_LB in the focus direction, and the switch 1311 is switched by changing the level of the S_FON signal, and the servo layer focus control is turned on.
  • the optical disc apparatus performs track pull-in processing on the recording layer track of the optical disc 101 (step S607).
  • the system control circuit 1301 changes the control signal related to tracking control, and then changes the R_TON signal from the Low level to the High level.
  • the switch 1311 is switched and the recording layer tracking control is turned on.
  • step S608 adjustment processing for optimizing various parameters in the optical disc apparatus is performed on the inserted optical disc 101 (step S608).
  • the various parameters include adjusting the amplification factor of the amplifier included in the recording layer focus control circuit 1502 and the recording layer tracking control circuit 1516 in accordance with the reflectance of the optical disc 101.
  • step S608 After performing step S608, a management information reading process for reading management information recorded on the optical disc 101 is performed (step S609).
  • step S609 the setup process ends (step S610).
  • step S610 the setup process ends (step S610).
  • timing of the adjustment process S607 is not limited to this, and part of the adjustment process may be performed before the focus pull-in process S605 or after the management information read process S609.
  • the circuit configuration of the servo system of the optical disc apparatus 101 after the setup process has been completed will be described.
  • 8 to 10 are tables for explaining the states of the tracking control system and the focus control system of the optical disc apparatus 101 in various operation states. In each table, names described in the column of the operation state will be described later.
  • the servo system circuit configuration of the optical disc apparatus 101 in this embodiment has four patterns depending on the operating state. Using the numbers shown in the No column, the state operating with the circuit configuration of No. 1 will be referred to as state 1.
  • FIG. 8 is a table showing the operating states of the tracking control system and the focus control system in various operating states and the names defined in this specification. For each operation state, two stages are indicated by broken lines. The upper part shows the control for the recording layer, and the lower part shows the control for the servo layer. Also, in the table, the part indicated by “-” indicates that control is not performed. For example, regarding state 1, it means that focus control is performed on the recording layer, but tracking control is not performed on the recording layer.
  • FIG. 9 shows values of control signals output from the system control circuit 1501 in order to realize the circuit configuration of the control system shown in FIG.
  • the part described as “NoCare” indicates that it may be a high level or a low level.
  • FIG. 10 shows which drive signal is used for focus driving and tracking driving of the objective lens and the relay lens as a result of the control signal shown in FIG.
  • the recording layer tracking control for driving the objective lens in the tracking direction even if the name of the drive signal is R_TRD signal, the selection state of the recording layer tracking error signal R_TE in the selector 1513 at the preceding stage is also important.
  • the objective lens tracking drive is the R_TRD signal, it also indicates which of the R_SubTE signal and the R_MainTE signal is selected as the R_TE signal.
  • the circuit configuration of the servo system after the setup process is completed corresponds to the state 4 in FIGS. That is, as shown in FIG. 8, both the recording layer and the servo layer are controlled for focus control, and only the recording layer is controlled for tracking control.
  • the control is recording layer MainSpot tracking control.
  • the tracking driving of the relay lens is not performed as shown in FIG.
  • the OL_TSEL signal is High and the R_TON signal is High
  • the objective lens is driven for tracking by the R_TRD signal as shown in FIG.
  • the R_MainTE signal is selected as the R_TE signal. That is, the recording layer MainSpot tracking control is performed as shown in FIG.
  • FIG. 7 shows a flowchart of the recording process of the optical disc apparatus 101 of the present embodiment when an instruction to record information is given from the host 114.
  • the optical disc apparatus 101 When the recording of information is instructed from the host 114, the optical disc apparatus 101 starts the recording process (step S701). In the recording process, the optical disk apparatus 101 first confirms whether or not the recording by the recording process is the first recording for the currently inserted optical disk (step S702). This can be determined, for example, from the information read out by the management information reading process in step S609 in the setup process shown in FIG. Alternatively, the seek operation may actually be performed in step S702 to read the management information and the like.
  • step S703 the optical disc apparatus 101 starts the objective lens drive servo layer tracking control (step S703). This process corresponds to switching the operation state in FIGS. 8 to 10 from state 4 to state 1.
  • both the recording layer and the servo layer are controlled for focus control, and only the servo layer is controlled for tracking control.
  • the control is objective lens driving servo layer tracking control.
  • step S703 the state 4 is switched to the state 1 by, for example, first setting the S_TON signal and the R_TON signal to the low level, setting the S_TRD signal and the T_TRD signal to the reference potential Vref, and then switching the OL_TSEL signal from the high level to the low level. Then, the S_TRD signal is set to High and track pull-in is performed with respect to the servo layer.
  • the circuit change of the tracking control system according to the present embodiment is performed by setting both the S_TON signal and the R_TON signal, which are signals for instructing on / off of the tracking control, to the low level, and then the signals OL_TSEL and RL_TSEL which are the circuit switching signals. This can be realized by switching R_TESEL as necessary, and then changing the S_TON signal and the R_TON signal to High level as necessary to perform track pull-in to a desired layer.
  • the optical disc apparatus 101 issues a command from the system control circuit 1501 to the slider control circuit 1521 to drive the slider motor 112 so that the optical pickup 103 comes to a predetermined radius (step S704).
  • the predetermined radius is assumed to be the innermost radius of the optical disc 102.
  • the optical disc apparatus 101 records a part of information instructed to be recorded by the host 114. At this time, recording is performed for two or more rotations of the disc (step S705). This operation is hereinafter referred to as initial recording.
  • the optical disc apparatus 101 After recording information of two or more revolutions of the disc in step S705, the optical disc apparatus 101 stops the initial recording (step S706).
  • step S706 the optical disc apparatus 101 ends the objective lens drive servo layer tracking control (step S707). This can be realized by setting the S_TON signal to a low level. After step S707, the process returns to step S702.
  • the disk device 101 issues a command from the system control circuit 1501 to the slider control circuit 1521 to The slider motor 112 is driven so that the pickup 103 comes to a predetermined radius (step S708).
  • the predetermined radius is a radius common to step S704 and is a radius of the innermost circumference of the optical disc 102.
  • step S708 information has been recorded in the past on the optical disk inserted at the time when the recording of information is instructed from the host 114, or the recording of information from the host 114 has occurred.
  • the processing after step S708 is performed in a state where the innermost radial position of the optical disc 102 is recorded over two or more tracks.
  • step S708 the optical disc apparatus 101 performs track pitch adjustment from step S709 to step S716.
  • the area where the track pitch adjustment is performed is an area recorded by the initial recording, and the initial recording in this embodiment can be said to be a process for creating a recording unit for adjusting the track pitch.
  • step S709 recording layer SubSpot tracking control is started (step S709). This process corresponds to switching the operation state in FIGS. 8 to 10 from state 1 to state 2.
  • the optical disc apparatus 101 performs a one-track jump in synchronization with the rotation of the optical disc 101 so as to keep following the same track (step S710).
  • the optical disc apparatus 101 stores the value of the R_MainTE signal monitored by the recording layer MainTE signal monitor circuit 1523 (step S711). Subsequently, the recording layer track pitch adjustment voltage generation circuit 1514 is instructed to change the voltage V_TpAdj of the R_TpAdj signal (step S712).
  • step S712 it is confirmed from the information of the R_MainTE signal monitored by the recording layer MainTE signal monitor circuit 1523 whether the level of the R_MainTE signal has changed across the reference potential Vref.
  • step S713 If the level of the R_MainTE signal does not change across the reference potential Vref (No in step S713), the process returns to step S711. That is, the operation of repeating steps S711 and S712 is repeated until the level of the R_MainTE signal changes across the reference potential Vref.
  • step S713 When the level of the R_MainTE signal changes across the reference potential Vref (Yes in step S713), the one-track jump operation is stopped in synchronization with the rotation of the optical disc 101 started in step S710 (step S714).
  • the optical disc apparatus 101 calculates the optimum value of the voltage V_TpAdj output from the recording layer track pitch adjustment voltage generation circuit 1514 from the voltage V_TpAdj set in Step S712 and the value of the R_MainTE signal stored at that time (Step S712). S715).
  • step S715 the optical disc apparatus 101 instructs the recording layer track pitch adjustment voltage generation circuit 1514 to change the voltage V_TpAdj of the R_TpAdj signal to an optimum value (step S716).
  • step S717 the optical disc apparatus 101 starts relay lens driving servo layer tracking control. This process corresponds to switching the operation state in FIGS. 8 to 10 from state 2 to state 3.
  • step S717 After starting relay lens drive servo layer tracking control in step S717, information is recorded, and all information instructed to be recorded by the host 114 is recorded (step S718). If the initial recording in step S705 has been performed, the recording of information is resumed from the recorded continuation. When the information recording is finished in step S718, the recording process is finished (step S719).
  • step S715 Before describing the method of calculating the optimum value of V_TpAdj in step S715, first, the effect of this embodiment will be described. Then, the calculation method of the optimal value of V_TpAdj for achieving the purpose will be described.
  • the effect of the present embodiment is that the problem in the case of performing the recording layer SubSpot tracking control can be solved. Therefore, first, the advantage of performing the recording layer SubSpot tracking control will be described. Subsequently, a problem when performing the recording layer SubSpot tracking control will be described, and finally, the effect of the present embodiment will be described.
  • FIG. 11 shows the positional relationship between the optical disc 102 and the laser spot when information is recorded on the recording layer without performing the recording layer SubSpot tracking control.
  • FIG. 11A shows an ideal state where the optical disk 102 is not inclined with respect to the objective lens.
  • the tracking control is performed by a method referred to as servo layer tracking control in this specification.
  • servo layer tracking control in this specification.
  • the servo layer laser spot S_LS is generated on the servo layer by the laser beam S_LB irradiated to the servo layer, and tracking control is performed using this.
  • the recording layer laser spot R_LS is generated in the recording layer by the laser beam R_LB irradiated to the recording layer, and information is recorded using this.
  • the servo layer laser spot S_LS and the recording layer laser spot R_LS are located on an axis perpendicular to the disk.
  • FIG. 11B shows a state where the optical disc 102 is tilted with respect to the objective lens
  • A shows the position of the recording layer laser spot R_LS when the optical disc 102 is not tilted with respect to the objective lens.
  • the recording layer laser spot R_LS when the optical disk 102 is tilted with respect to the objective lens does not coincide with A.
  • Factors that change the relative inclination of the optical disk 102 and the objective lens include a change in warpage of the optical disk itself due to temperature and humidity, and a change in the relative positional relationship between the optical disk device 101 and the optical disk 102 due to chucking.
  • the adjacent recording layer track is irradiated with the recording layer sub-spot R_SubLS to perform tracking control, and the recording layer main is located at a position separated by Tp in the radial direction.
  • the position of the spot R_MainLS is controlled. Therefore, by using the recording layer SubSpot tracking control, it is possible to solve the problem of overwriting recorded data when the relative inclination of the optical disk 102 and the objective lens changes. That is, by using the recording layer SubSpot tracking control, additional information can be recorded on the grooveless disc.
  • the recording layer SubSpot tracking control is a control method that can realize additional recording of information on the grooveless disc.
  • another problem exists in realizing the recording layer SubSpot tracking control. Next, this problem will be described.
  • FIG. 12 is a schematic diagram showing a laser spot on the recording layer when the recording layer SubSpot tracking control is performed.
  • the dotted line indicates the position of the track formed in the recording layer, and the recording layer sub-spot R_SubLS exists at a position separated from the recording layer main spot R_MainLS by the track pitch Tp of the servo layer in the radial direction.
  • the distance between the center of the recording layer main spot R_MainLS and the center of the recording layer sub-spot R_SubLS is d, and the angle between the line segment connecting the center of the recording layer main spot R_MainLS and the center of the recording layer sub-spot R_SubLS and the tangential direction is ⁇ . Show.
  • the distance d and the angle ⁇ vary due to reasons such as component manufacturing variations and assembly variations. When the variation occurs, the track pitch of the recording layer track formed in the recording layer deviates from Tp which is the design center.
  • the track pitch of the recording layer track deviates from Tp, an error occurs in the calculation when seeking, and seek performance deteriorates. Further, when the track pitch is reduced, the reproduction performance is deteriorated due to the influence of adjacent marks. Further, when the track pitch of the recording layer track changes, the recording capacity per layer also changes, and the data capacity of the optical disc 102 cannot be defined.
  • a problem in performing the recording layer SubSpot tracking control is that the track pitch of the recording layer track formed on the recording layer is deviated from Tp due to manufacturing variations or assembly variations of parts.
  • FIG. 13 is a schematic diagram showing a laser spot on the recording layer when the recording layer SubSpot tracking control is performed.
  • This shows a case where the track pitch of the recording layer track formed on the recording layer is deviated from Tp due to parts manufacturing variation or assembly variation, and shows a case where the track pitch is shortened by ⁇ Tp. ing. It is assumed that information is recorded from the inner periphery toward the outer periphery. That is, the left direction in the figure corresponds to the inner circumferential direction.
  • FIG. 13A shows a case where the recording layer SubSpot tracking control is performed without using this embodiment, and the track pitch of the recording layer track is Tp ⁇ Tp.
  • the control position of the recording layer sub-spot R_SubLS is changed. That is, the recording layer sub-spot R_SubLS is not controlled to follow the adjacent track, but is controlled to a position on the outer peripheral side by ⁇ Tp from the adjacent track. Thereby, the track pitch of the recording layer track becomes Tp.
  • Such a change in the control position can be realized by applying an offset to the tracking error signal.
  • the recording layer track pitch adjustment voltage generation circuit 1514 functions as an offset output unit.
  • the voltage V_TpAdj output from the recording layer track pitch adjustment voltage generation circuit 1514 corresponds to the offset.
  • the track pitch is shifted from the state as shown in FIG. 13A to the state shown in FIG. 13B where the track pitch of the recording layer track becomes Tp.
  • the value of the R_MainTE signal when the voltage V_TpAdj is changed is monitored. This meaning will be described with reference to FIGS.
  • FIG. 14 is a schematic diagram showing a laser spot on the recording layer when the voltage V_TpAdj is changed.
  • FIG. 14A shows the initial state, and the state where the track pitch of the recording layer track is Tp ⁇ Tp is the initial state as in FIG.
  • FIG. 14B shows a state in which the voltage V_TpAdj is an optimal value and the track pitch is Tp.
  • the optimum value of the optimum V_TpAdj is V_BestTpAdj.
  • FIG. 14C shows a case where the value of the voltage V_TpAdj is 2 ⁇ V_BestTpAdj.
  • FIG. 14C shows a state in which the recording layer sub-spot R_SubLS has moved by 2 ⁇ ⁇ Tp from the initial state of FIG. Therefore, in the comparison with the optimum state in FIG. 14B, the recording layer sub-spot R_SubLS has a relationship of moving by ⁇ Tp to the outer peripheral side.
  • (a) and (c) are in a symmetrical relationship with the optimum state (b) as the center.
  • FIG. 15 shows the waveform of the R_MainTE signal when the recording layer main spot R_MainLS crosses the track.
  • (A), (b), and (c) in FIG. 15 correspond to (a), (b), and (c) in FIG. 14, respectively.
  • the R_MainTE signal is generated by the DPD (Differential Phase. Detection) method
  • the R_MainTE signal becomes a triangular wave as shown in FIG.
  • a region A having a positive slope is called a negative period region, and this range is a range in which tracking control can be controlled.
  • a region where the slope indicated by B is negative is a region where tracking control cannot be performed.
  • the R_MainTE signal takes the value of the reference potential Vref. Therefore, in FIG. 15B, the R_MainTE signal is Vref. Further, (a) and (c) have a symmetrical relationship with the optimum state (b) as the center as shown in FIG. This is because the R_MainTE signal is a signal indicating the radial distance between the recording layer main spot R_MainLS and the adjacent track.
  • FIG. 16 shows a signal for each part during the track pitch adjustment of this embodiment and a method for calculating the optimum value of the voltage V_TpAdj.
  • FIG. 16A shows the value of the voltage V_TpAdj during the track pitch adjustment of this embodiment
  • FIG. 16B shows the R_MainTE signal monitored by the recording layer MainTE signal monitor circuit 1523 at that time. (DC level).
  • M_TE the value of the R_MainTE signal monitored by the recording layer MainTE signal monitor circuit 1523
  • V_TpAdj the value of V_TpAdj for the i-th time
  • M_TE [i] the value of the R_MainTE signal monitored for the i-th time
  • the change amount of the voltage V_TpAdj that is changed in step S712 is a fixed value
  • the voltage V_TpAdj changes stepwise in the vertical axis direction at equal intervals.
  • changing the voltage V_TpAdj output from the recording layer track pitch adjustment voltage generation circuit 1514 at equal intervals is equivalent to moving the recording layer sub-spot R_SubLS at equal intervals in the radial direction. To do.
  • the DC level of the R_MainTE signal is a signal indicating the radial distance between the recording layer main spot R_MainLS and the adjacent track
  • the voltage V_TpAdj changes stepwise as shown in FIG. 16A
  • the R_MainTE signal The DC level also changes stepwise as shown in FIG.
  • V_TpAdj [i] and M_TE [i] obtained in this way are plotted on a graph of V_TpAdj and M_TE as shown in FIG. 16C, each data is arranged in a straight line.
  • the optimum value of the voltage V_TpAdj to be finally obtained in the track pitch adjustment is the value of the voltage V_TpAdj that causes the recording layer main spot R_MainLS to overlap the adjacent track.
  • the value of the voltage V_TpAdj is obtained so that the DC level of the R_MainTE signal monitored by the recording layer MainTE signal monitor circuit 1523 becomes the reference potential Vref.
  • step S716 the optimum value calculated in step S715 is set, and the state is continued thereafter.
  • the problem in performing the recording layer SubSpot tracking control is that the distance in the radial direction between the recording layer main spot R_MainLE and the recording layer sub-spot R_SubLS is the track pitch Tp of the servo layer as shown in FIGS. It was to deviate from.
  • the control position of the recording layer sub-spot R_SubLS can be changed to the optimum position so that the state shown in FIG.
  • the track pitch of the recording layer track can be set to Tp.
  • the effect of this embodiment is that the radial distance between the recording layer main spot R_MainLE and the recording layer sub-spot R_SubLS deviates from the track pitch Tp of the servo layer for reasons such as manufacturing variations and assembly variations of parts.
  • the track pitch of the recording layer track can be set to Tp. Thereby, deterioration of seek performance and reproduction performance can be suppressed.
  • step S718 in which information is recorded by the recording layer sub-spot tracking control the optimum V_TpAdj has already been set.
  • the track pitch adjustment is performed before the information is recorded by the recording layer sub-spot tracking control.
  • the track pitch adjustment is an adjustment necessary for recording information by the recording layer sub-spot tracking control, it is obvious that this order is necessary.
  • an operation of performing one track jump in synchronization with the rotation is performed.
  • the track pitch adjustment monitors the R_MainTE signal, it is desirable to monitor one rotation of the disk and use the average value (ie, DC level). From the above, in order to adjust the track pitch while performing one track jump in synchronization with the rotation, it is necessary to adjust the track pitch in the recorded area of two or more tracks. Therefore, in the initial recording in step S705, it is necessary to perform recording for two or more rotations of the disc.
  • FIG. 15 shows the waveform of the R_MainTE signal when the recording layer main spot R_MainLS crosses the track, but the R_SubTE signal has the same waveform.
  • the controllable range of the tracking control is the negative feedback region indicated by A in FIG. 15. Therefore, the value of the voltage V_TpAdj to be changed by the track pitch adjustment is such that the detrack amount related to the R_SubTE signal is within the negative feedback region. It is necessary to set within the range that does not appear. In the case of FIG. 15, this corresponds to setting the absolute value of the voltage V_TpAdj within a range that does not exceed the absolute value of the R_SubTE signal at both ends of the region A.
  • the value of the voltage V_TpAdj is adjusted so that the DC level of the R_MainTE signal monitored by the recording layer MainTE signal monitor circuit 1523 becomes the reference potential Vref.
  • the optical disc apparatus 101 may be provided with a circuit for removing the offset.
  • the adjustment target potential of the R_MainTE signal deviates from the reference potential Vref of the signal processing circuit 105 by the amount of offset to be removed. Therefore, more precisely, it is more accurate to express that the DC level of the R_MainTE signal monitored by the recording layer MainTE signal monitor circuit 1523 is adjusted to a predetermined value.
  • the predetermined value is equal to the reference potential Vref.
  • the recording layer main spot R_MainLS and the R_MainTE signal which is a signal indicating the radial distance between adjacent tracks, are monitored to adjust the track pitch.
  • another signal may be used as the signal monitored by the track pitch adjustment as long as the signal exhibits a behavior corresponding to the radial distance between the recording layer main spot R_MainLS and the adjacent track.
  • a reproduction signal can be used as such a signal.
  • the optical disc apparatus 101 may be provided with a circuit for monitoring the amplitude of the reproduction signal obtained by R_MainLS, and the track pitch adjustment for obtaining the value of the voltage V_TpAdj that maximizes the amplitude may be performed.
  • the R_MainTE signal and the reproduction signal obtained by R_MainLS have been described as examples of signals to be monitored when track pitch adjustment is performed. These are common in that they are generated from a detector 1314 that detects the intensity of light reflected at the recording layer main spot R_MainLS. That is, the output of the detector 1314 may be used as a signal for confirming whether or not the recording layer main spot R_MainLS is irradiated on the adjacent track. Further, it is obvious that signals other than the above two may be monitored as long as the signals are generated from the detector 1314.
  • the problem in the case of performing the recording layer SubSpot tracking control can be solved, and the recording layer SubSpot tracking control can be appropriately performed.
  • the track pitch of the recording layer track can be made to coincide with the track pitch Tp of the servo layer with high accuracy, and good seek performance and good reproduction performance can be achieved. Furthermore, the data capacity of the optical disk 102 can be defined reliably.
  • the track pitch adjustment is performed using the recording unit of the optical disc 102 inserted in the optical disc apparatus 101 in the recording process when the host 114 is instructed to record information. This is for solving the problem that the track pitch of the recording layer track deviates from Tp, and there are two causes for this problem in this specification. One is the manufacturing variation or assembly variation of the parts, and the other is the warp of the optical disc itself or the inclination when the optical disc 102 is mounted.
  • the recording layer track pitch deviation is a value specific to the pickup.
  • the present embodiment is an embodiment paying attention to this.
  • FIG. 1 is a block diagram of the first embodiment.
  • the configuration of the servo error signal generation circuit 104 and the configuration of the signal processing circuit 105 are also the same as those in FIGS. 2 and 3 which are the configuration diagrams of the first embodiment.
  • FIG. 17 shows a flowchart of the recording process of this embodiment when the host 114 is instructed to record information.
  • the optical disc apparatus 101 When the recording of information is instructed from the host 114, the optical disc apparatus 101 starts the recording process (step S1701). In the recording process, the optical disk apparatus 101 first confirms whether or not the recording by this recording process is the first recording for the currently inserted optical disk (step S1702).
  • the optical disc apparatus 101 starts the objective lens drive servo layer tracking control (step S1703).
  • the optical disc apparatus 101 issues a command to the slider control circuit 1521 from the system control circuit 1501, and drives the slider motor 112 so that the optical pickup 103 comes to a predetermined radius (step S1704).
  • the predetermined radius is assumed to be the innermost radius of the optical disc 102.
  • the optical disc apparatus 101 records a part of information instructed to be recorded by the host 114. At this time, recording is performed for one or more rotations of the disc (step S1705). This operation is hereinafter referred to as initial recording.
  • the optical disc apparatus 101 After recording information of one or more revolutions of the disc in step S1705, the optical disc apparatus 101 stops the initial recording (step S1706).
  • step S1706 the optical disc apparatus 101 ends the objective lens drive servo layer tracking control (step S1707).
  • the optical disk apparatus 101 instructs the recording layer track pitch adjustment voltage generation circuit 1514 to output the R_TpAdj signal.
  • the voltage V_TpAdj is changed to a predetermined value (step S1708).
  • a predetermined value a value stored in a non-volatile memory (not shown) provided in the system control circuit 1501 is used.
  • step S1716 the optical disc apparatus 101 starts recording layer SubSpot tracking control (step S1709), and then starts relay lens drive servo layer tracking control (step S1710).
  • step S1717 After starting the relay lens drive servo layer tracking control in step S1717, information is recorded, and all information instructed to be recorded by the host 114 is recorded (step S1711). If the initial recording in step S1705 has been performed, the recording of information is resumed from the recorded continuation. When the information recording is finished in step S1711, the recording process is finished (step S1712).
  • the present embodiment assumes a case in which the problem that the track pitch of the recording layer track deviates from Tp is caused by the manufacturing variation and assembly variation of components.
  • the component variation and the assembly variation referred to here are related to the components constituting the pickup 103, and are values specific to the pickup 103. Therefore, it is not necessary to adjust the track pitch every time the recording operation is performed as in the first embodiment, and a value unique to the apparatus may be set before recording information by the recording layer sub-spot tracking control.
  • the distance between the two laser spots R_MainLS and R_SubLS generated on the recording layer at the time of manufacturing the optical disc apparatus 101 is investigated, and the investigation result is provided in the system control circuit 1501.
  • Store in non-volatile memory Before the information is recorded by the recording layer sub-spot tracking control, the value is read and the voltage V_TpAdj of the recording layer track pitch adjustment voltage generation circuit 1514 is set to an optimum value.
  • the same effect as in the first embodiment can be achieved. That is, even when the radial distance between the recording layer main spot R_MainLE and the recording layer sub-spot R_SubLS deviates from the track pitch Tp of the servo layer as shown in FIGS. 14A and 14C.
  • the control position of the recording layer sub-spot R_SubLS can be changed to the optimum position, and the state shown in FIG. 14B can be obtained.
  • the problem in the case of performing the recording layer SubSpot tracking control can be solved, and the recording layer SubSpot tracking control can be appropriately performed.
  • the track pitch of the recording layer track can be made to coincide with the track pitch Tp of the servo layer with high accuracy, and good seek performance and good reproduction performance can be achieved. Furthermore, the data capacity of the optical disk 102 can be defined reliably.
  • the structure of the optical disc 102 is such that the recording surface coated with the recording film is laminated in the film thickness direction.
  • the application range of the present invention is not limited to the optical disk having the structure shown in FIG. Any optical disc having a recording layer capable of generating a focus error signal can be applied.
  • the recording layer focus error may occur even in an optical disc in which information is recorded or reproduced by irradiating a uniform medium with a laser beam having a wavelength of 405 nm.
  • a signal can be generated, focus control can be performed on the information recording surface, and the present invention can be applied to tracking control within the surface.
  • a uniform medium has a structure for specifying the recording position of information in the recording medium, and a recording layer focus error signal is generated from the output signal of the detector by the structure, so that the information is obtained in a planar shape.
  • the present invention can be similarly applied to an optical disc in which recording is performed to form a recording layer.
  • the optical disk 102 has a structure having a servo layer, but the present invention can also be applied to an optical disk having no servo layer.
  • the present invention when two laser spots are arranged in the recording layer and tracking is performed with one laser spot and recording light emission is performed with the other laser spot, the track pitch formed in the recording layer is the design target value (above).
  • the problem of deviating from Tp) is solved. Therefore, the present invention can be similarly applied to an optical disc having no servo layer in that the radial distance between mark rows formed on the recording layer is adjusted.
  • the first recording is performed only when the first recording is instructed for the currently inserted optical disk. Therefore, even when there are a plurality of recording layers, initial recording was performed on one of the layers to create a recording portion, and the track pitch was adjusted in the recording portion.
  • the other recording layers were operated using the values obtained by adjusting the track pitch in the above layers.
  • the recording portion may be created in each layer and the track pitch may be adjusted. As a result, even when the interlayer thickness is not uniform and the recording layer is inclined in some recording layers, the track pitch of the recording layer track can be adjusted more accurately to be the same as the servo layer track pitch. it can.
  • the half-pitch position where the first recording is performed is the innermost circumference of the optical disc 102.
  • the radial position where the initial recording is performed may be any radial position on the optical disc 102.
  • the track pitch adjustment is performed at the radial position where the initial recording is performed.
  • the track pitch may be adjusted using any of the recording portions.
  • the initial recording in the above embodiment is an operation performed after the host 114 is instructed to record information, it may be performed before that. For example, you may perform by a setup process.
  • the track pitch adjustment is performed at a plurality of radial positions, and the value of the voltage V_TpAdj output from the recording layer track pitch adjustment voltage generation circuit 1514 is changed according to the radial position, thereby changing the inclination of the optical disk 102 depending on the radius Even so, it can be operated so that the track pitch of the recording layer track is the same as the servo layer track pitch.
  • the method for determining the voltage V_TpAdj according to the radial position the track pitch is adjusted at the innermost circumference and the outermost circumference. There is a method of linear interpolation.
  • the radial distance between the two laser spots R_MainLS and R_SubLS generated on the recording layer is arranged so as to be substantially equal to the track pitch Tp of the servo layer.
  • the distance may be other than Tp.
  • it may be an integral multiple of the track pitch Tp.
  • the recording layer sub-spot R_SubLS is irradiated onto the recording layer track that is two tracks away from the recording track, thereby recording at a position on the outer circumference side by twice Tp.
  • the position of the layer main spot R_MainLS is controlled and information is recorded. Also in this case, since overwriting of recorded data can be prevented when the relative inclination of the optical disc 102 and the objective lens changes, the advantage of the recording layer SubSpot tracking control is maintained also in that case.
  • the radial distance between the two laser spots R_MainLS and R_SubLS generated on the recording layer may be half of the track pitch Tp of the servo layer.
  • the case where the track pitch is half of the track pitch Tp is a case where the servo layer has a CAPA (Complementary Allocated Pit Address) structure such as a DVD-RAM as described in Patent Document 2.
  • CAPA Common Allocated Pit Address
  • the distance between the mark rows in the radial direction is half the track pitch.
  • the track pitch of the recording layer track is half of Tp, but the distance in the radial direction of the laser spots R_MainLS and R_SubLS is the same as the track pitch of the recording layer track. Since the track pitch adjustment is an adjustment related to the recording layer, it is the same as in the first embodiment that the track pitch must be adjusted in an area where two or more tracks are recorded in the recording layer. That is, in the initial recording when the radial distance between the laser spots R_MainLS and R_SubLS is half the track pitch Tp of the servo layer, it is necessary to perform recording for two or more rotations of the disk.
  • the R_SubTE signal is generated by the DPD method.
  • the present invention can be similarly applied when other generation methods are used.
  • the DPP method is known as a method for generating different tracking error signals, and in this case as well, it can be similarly applied, including the discussion regarding the negative feedback region described above.
  • the optical disc apparatus 101 includes the recording layer track pitch adjustment voltage generation circuit 1514, and the track pitch adjustment is performed by adjusting the voltage V_TpAdj output from the recording layer track pitch adjustment voltage generation circuit 1514.
  • the present invention finds that the track pitch of the recording layer track formed in the recording layer deviates from Tp when performing the recording layer SubSpot tracking control, and is an invention for the problem. Therefore, the method of adjusting the track pitch may be other than the method of adjusting the voltage V_TpAdj output from the recording layer track pitch adjustment voltage generation circuit 1514.
  • the optical pickup 103 includes an optical element capable of adjusting a radial distance between two laser spots R_MainLS and R_SubLS generated on the recording layer, and the optical element 103 is used to adjust the radial distance between the two laser spots. The distance may be adjusted.
  • the offset is applied to the tracking error signal, and the voltage V_TpAdj output from the recording layer track pitch adjustment voltage generation circuit 1514 is added to the voltage of the tracking error signal by the adder 1515.
  • offset addition may take a form other than voltage addition.
  • the signal processing circuit 105 is a digital LSI, it is obvious that application of an offset can be read as addition of a digital value.
  • the recording layer tracking error signal R_TE to which the voltage V_TpAdj output from the recording layer track pitch adjustment voltage generation circuit 1514 is added is generated by the servo error signal generation circuit 104 shown in FIG.
  • Each error signal generation circuit in the servo error signal generation circuit 104 preferably performs AGC (Auto Gain Control) based on the total light amount.
  • the recording layer sub-tracking error signal generation circuit 1401 performs normalization based on the AGC based on the total light amount, that is, the total electric signal received by the detector 1324, so that, for example, the reflected light amount changes depending on the recording state of the front recording layer. Can also remove the effect. Therefore, the value to which the voltage V_TpAdj output from the recording layer track pitch adjustment voltage generation circuit 1514 is added can be constant regardless of the recording state of the previous recording layer.
  • the voltage V_TpAdj output from the recording layer track pitch adjustment voltage generation circuit 1514 is added as the R_TE signal that is the input signal of the recording layer tracking control circuit 1516, but the position where the voltage V_TpAdj is added is It may be a signal inside the recording layer tracking control circuit 1516.
  • the same laser power control circuit 1301 is used to drive the laser diode 1302 and the laser diode 1315.
  • each laser diode may be provided with a laser power control circuit unique to each laser diode.
  • the spherical aberration correction element 1309 may be disposed at a position that affects both the 405 nm optical system and the 650 nm optical system.
  • the spherical aberration correction element 1309 may be disposed between the quarter wavelength plate 1310 and the dichroic mirror 1308. .
  • FIG. 20 shows the structure (cross section) of an optical disc 222 targeted by this embodiment.
  • the optical disk 222 shown in the figure is an optical disk 222 having one guide layer with grooves and one or more flat recording layers without grooves.
  • the groove of the guide layer is a spiral groove centered on the disk rotation axis, like the groove found on a disk such as DVD or BD.
  • the groove has a undulation structure (wobble) having a substantially constant period in the length direction as seen in a disk such as a DVD or a BD.
  • information indicating the current position (address) is added to the guide layer so as to be seen on a disc such as a DVD or a BD.
  • a method of adding an address includes adding a portion to be modulated to wobble and adding a pit to the groove structure.
  • the objective lens 311 in the figure is an objective lens 311 of an optical disc recording / reproducing apparatus (not shown) for condensing a laser beam on the optical disc 222.
  • two different light beams pass through the objective lens 311, one light beam generates a laser spot LSg on the guide layer of the optical disk 222, and the other light beam is out of a plurality of recording layers of the optical disk 222.
  • the laser spot LSW is generated.
  • the optical disk 222 targeted by this embodiment performs recording or reproduction using two or two or more light beams.
  • FIG. 19 is a block diagram showing an embodiment of the optical disc recording / reproducing apparatus 221 according to the present invention.
  • the optical disk recording / reproducing apparatus 221 records or reproduces information by irradiating an optical disk 222 mounted on the apparatus with laser light, and communicates with a host 223 such as a PC (Personal Computer) through an interface such as SATA (Serial Advanced Technology Attachment). Communicate.
  • a host 223 such as a PC (Personal Computer) through an interface such as SATA (Serial Advanced Technology Attachment). Communicate.
  • the optical disc recording / reproducing apparatus 221 includes a controller 201, a signal processing unit 202, an optical pickup 203, a slider motor 204 that moves the optical pickup 203 in the radial direction of the optical disc 222, a slider driving unit 205 that drives the slider motor 204, Aberration correction driving means 206 for driving the spherical aberration correction element 309 provided in the optical pickup 203, a spindle motor 207 for rotating the optical disk 222, and a rotation signal for rotating the spindle motor 207 are generated.
  • the optical pickup 203 performs servo control on the guide layer, and data on a guide layer optical system for reproducing an address and disc-specific information corresponding to the position on the disc, and a plurality of recording layers at different distances from the guide layer. Is composed of a recording layer optical system for recording / reproducing data.
  • the laser driver 301 is controlled by the controller 201 and outputs a current for driving the laser diode 302.
  • This drive current is applied with high frequency superposition of several hundred MHz in order to suppress laser noise.
  • the laser diode 302 emits a laser beam LBw having a wavelength of 405 nm, for example, with a waveform corresponding to the drive current.
  • the emitted laser light becomes parallel light by the collimator lens 303, a part of the light is reflected by the beam splitter 304, and is condensed on the power monitor 306 by the condenser lens 305.
  • the power monitor 306 feeds back a current or voltage corresponding to the intensity of the laser light to the controller 201.
  • the intensity of the laser beam LBw focused on the recording layer of the optical disc 222 is maintained at a desired value such as 2 mW.
  • the laser beam LBw that has passed through the beam splitter 304 is reflected by the polarization beam splitter 307, and the convergence / divergence is controlled by the spherical aberration correction element 309 driven by the aberration correction drive means 206, and passes through the dichroic mirror 308.
  • the dichroic mirror 308 is an optical element that reflects light of a specific wavelength and transmits light of other wavelengths. Here, it is assumed that light having a wavelength of 405 nm is transmitted and light having a wavelength of 650 nm is reflected.
  • the laser beam LBw that has passed through the dichroic mirror 308 becomes circularly polarized light by the quarter-wave plate 310 and is condensed as a laser spot LSW on the recording layer of the optical disc 222 by the objective lens 311.
  • the spherical aberration correction element 309 is controlled from the controller 201 via the aberration correction driving means 206 so as to be at a predetermined position corresponding to the recording layer of the grooveless disk.
  • the intensity of the laser beam LBw reflected by the optical disc 222 is modulated in accordance with information recorded on the optical disc 222.
  • the light is linearly polarized by the quarter-wave plate 310, passes through the dichroic mirror 308, and passes through the polarization beam splitter 307 and the spherical aberration correction element 309.
  • the transmitted laser light LSW is condensed on the detector 314 by the condenser lens 313.
  • the detector 314 detects the intensity of the laser beam LBw and outputs a signal corresponding to the intensity to the signal processing means 202.
  • the focus error signal generation unit 211 generates a recording layer focus error signal for the recording layer from the signal output from the detector 314.
  • the focus control unit 212 outputs a focus drive signal corresponding to the focus error signal to the focus drive unit 213 in response to a command signal from the controller 201.
  • the focus drive unit 213 drives the actuator 312 according to the focus drive signal to displace the position of the objective lens 311 in the direction perpendicular to the recording surface, and the recording layer focus servo so that the laser beam LBw is focused on the recording layer. Take control.
  • the signal output from the detector 314 is also input to the tracking error signal generation unit 214 to generate a recording layer tracking error signal for the recording layer.
  • FIG. 28 shows an internal configuration of the tracking error signal generation unit 214.
  • the tracking error signal generation unit 214 performs tracking using the light spot 501 and the SUB tracking error signal generation unit 1101 that generates the tracking error signal from the light spot 502 and the main tracking error signal generation unit 1102 that generates the tracking error signal from the light spot 500.
  • a SUB tracking error signal generating unit 1103 and a tracking error signal selecting unit 1104 for selecting a tracking error signal to be output depending on a state such as recording, reproduction, and OPC are provided.
  • the tracking error signal selection unit 1104 outputs, for example, the tracking error signal generated by the Main tracking error signal generation unit 1102 when reproducing information, and the tracking error generated by the subsequent Sub tracking error signal generation unit 1103 during recording. It operates by switching the tracking error signal to be output as described later during OPC.
  • the tracking error signal generating means there are three light spots 500 to 502 focused on the recording layer.
  • the tracking error signal generating means 214 can output the tracking error signal.
  • the tracking control unit 215 outputs a tracking drive signal corresponding to the output of the tracking error signal generation unit 214 or the tracking error signal generation unit 210 to the tracking drive unit 216 according to a control signal from the controller 201.
  • the laser driver 301 is controlled by the controller 201 and outputs a current for driving the laser diode 315.
  • the laser diode 315 emits laser light LBg having a wavelength of 650 nm, for example.
  • a part of the laser beam LBg is monitored by a power monitor 319 through a collimator lens 316, a beam splitter 317, and a condenser lens 318.
  • the intensity of the laser beam LBg focused on the guide layer of the optical disc 222 is maintained at a desired power such as 3 mW.
  • the laser beam LBg that has passed through the beam splitter 317 passes through the polarization beam splitter 320 and is controlled by the relay lens 321 to converge, diverge, and change the optical axis.
  • the laser beam LBg that has passed through the relay lens 321 is reflected by the dichroic mirror 308, passes through the quarter-wave plate 310, and is condensed as a laser spot LSg on the guide layer of the optical disc 222 by the objective lens 311.
  • the laser beam LBg reflected by the optical disk 222 is reflected by the polarization beam splitter 320 and condensed on the detector 323 by the condenser lens 322.
  • the Detector 323 detects the intensity of the laser beam and outputs a signal corresponding to this to signal processing means 202.
  • the signal processing means 202 is a synchronization signal for controlling the rotation of the optical disc 222 by a signal corresponding to a track formed by wobbling the guide layer output from the detector 323, and a clock used as a reference for recording or reproduction A signal is generated, and an address corresponding to the position on the optical disc 222 that the laser spot LSg follows is reproduced and output to the controller 201.
  • the synchronization signal output from the signal processing unit 202 and the FG signal output from the spindle driving unit 209 are input to the spindle control unit 208.
  • the spindle control means 208 outputs a spindle drive signal based on an FG signal having a frequency corresponding to the rotational speed of the spindle motor 207 when the optical disk 222 is rotated at a constant angular velocity by the control signal from the controller 201, and the optical disk 222 is When rotating at a constant linear velocity, a spindle drive signal based on the synchronization signal reproduced from the guide layer is output.
  • the spindle driving means 209 performs spindle control so that the rotational speed of the optical disc 222 becomes a predetermined value by driving the spindle motor 207 in accordance with the spindle driving signal.
  • the focus error signal generation unit 217 generates a guide layer focus error signal corresponding to the deviation between the guide layer of the optical disc 222 and the in-focus position of the laser spot LSg from the signal output from the detector 323, and the relay lens control unit 218 A relay lens driving signal corresponding to the layer focus error signal is generated.
  • the relay lens driving means 219 performs guide layer focus servo control so that the laser spot LSg is focused on the guide layer by driving the relay lens 321 according to the relay lens drive signal.
  • the relay lens driving means 219 changes the relative position in the radial direction between the laser spot LSg and the laser spot LSw by driving the relay lens 321 to change the optical axis according to the tracking drive signal.
  • the tracking error signal generation unit 210 generates a guide layer tracking error signal corresponding to the positional deviation between the track of the guide layer of the optical disc 222 and the laser spot LSg from the signal output from the detector 323, and the tracking control unit 215 Output to.
  • the tracking control unit 215 outputs a tracking drive signal corresponding to the output of the tracking error signal generation unit 214 or the tracking error signal generation unit 210 to the tracking drive unit 216 according to a control signal from the controller 201.
  • the laser spot LSW is recorded on the recording layer by driving the actuator 312 with the focus drive signal generated based on the recording layer focus error signal output from the focus error signal generating unit 211.
  • the recording layer focus servo control is performed so as to focus on the layer, and the relay lens 321 is driven by the relay lens drive signal generated based on the guide layer focus error signal output from the focus error signal generation unit 217.
  • Guide layer focus servo control is performed so that the laser spot LSg is focused on the guide layer in the recording layer.
  • the tracking drive signal generated based on the tracking error signal output from the tracking error signal generating unit 214 or the tracking error signal generating unit 210 from the tracking control unit 215 by the control signal from the controller 201 is sent to the tracking driving unit 216. Is output.
  • the tracking drive means 216 drives the actuator 312 and the relay lens 321 according to the tracking drive signal, so that the laser spot LSg follows the track of the guide layer, and the light spot 501 or the light spot 502 that does not perform recording is recorded on the recording layer. Tracking servo control is performed so as to follow the mark row.
  • the slider control means 220 that receives the control signal from the controller 201 outputs a slider drive signal for driving the slider motor 204 based on the average value of the tracking drive signal.
  • the slider motor 204 is driven by the slider drive means 205, and the optical pickup 203 is moved in the disk radial direction so that the actuator 312 operates in the vicinity of the center position of the movable range in the disk radial direction.
  • Data to be recorded on the recording layer input from the host 223 and address information corresponding to the position on the optical disc 222 where the data is recorded are output from the controller 201 to the signal processing means 202.
  • the signal processing means 202 modulates the input data and address information by a predetermined method based on the reference clock signal reproduced from the guide layer, and outputs it to the laser driver 301.
  • the laser driver 301 outputs a drive current corresponding to the output of the signal processing means 202 to the laser diode 302, and the laser diode 302 emits the laser beam LBw with a corresponding intensity, so that recording is performed on the recording layer of the optical disc 222.
  • recording can be performed on the recording layer at the focal distance between the light spot 500 for recording and the light spot 501 or the light spot 502 for servo control.
  • the light spot 500 and the light spot 501 or servo spot 502 for which servo control is performed at the same focal distance as the track spacing of the guide layer information is recorded on the recording layer in the same locus as the spiral of the guide layer track. Can be done.
  • the guide layer track is changed from the outer periphery to the inner periphery.
  • a recording mark can be formed in a spiral shape from the outer periphery to the inner periphery.
  • the actuator 312 When reproducing the information recorded on the recording layer, the actuator 312 is driven by the focus drive signal generated based on the recording layer focus error signal output from the focus error signal generating means 211, thereby causing the recording layer to laser. Recording layer focus servo control is performed so that the spot LSW is focused on the recording layer. Further, by driving the relay lens 321 with the relay lens driving signal generated based on the guide layer focus error signal output from the focus error signal generating means 217, the laser spot LSg is focused on the guide layer at the guide layer. The guide layer focus servo control is performed.
  • the tracking error detection unit 214 outputs a tracking error signal corresponding to the deviation between the track formed by the locus of information recorded on the recording layer and the light spot 500 irradiated on the recording layer.
  • a tracking drive signal generated based on the recording layer tracking error signal output from the tracking error signal generation unit 214 is output from the tracking control unit 215 to the tracking drive unit 216 by the control signal from the controller 201.
  • the tracking drive means 216 drives the actuator 312 according to the tracking drive signal, and tracking servo control is performed so that the light spot 500 follows the track formed by the locus of information recorded on the recording layer, and recording is performed from the detector 314.
  • a reproduction signal from the layer is output.
  • the slider control means 220 that receives the control signal from the controller 201 outputs a slider drive signal for driving the slider motor 204 based on the average value of the tracking drive signal.
  • the slider motor 204 is driven by the slider drive means 205, and the optical pickup 203 is moved in the disk radial direction so that the actuator 312 operates in the vicinity of the center position of the movable range in the disk radial direction.
  • the signal processing means 202 generates a synchronization signal for controlling the rotation of the optical disc 222 and a clock signal serving as a reference for reproduction from the input reproduction signal.
  • the signal processing unit 202 performs processing such as amplification, equalization, and decoding on the reproduction signal, and outputs the decoded data and address information corresponding to the position of the data on the optical disk 222 to the controller 201.
  • the controller 201 outputs the reproduced data to the host 223.
  • each laser diode may be provided with a laser driver specific to it.
  • the spherical aberration correction element 309 may be disposed at a position that affects both the 405 nm optical system and the 650 nm optical system, and may be disposed between the quarter wavelength plate 310 and the dichroic mirror 308, for example. .
  • FIG. 21 shows a processing flow of the optical disc recording / reproducing apparatus 221 when the optical disc 222 is inserted into the optical disc recording / reproducing apparatus 221.
  • the optical disc recording / playback device 221 checks the presence / absence of a disc and the disc type in S402. At this time, for example, the optical disc recording / reproducing apparatus 221 can irradiate the optical disc 222 with laser light and perform recognition by reflected light.
  • adjustment processing for making various parameters in the optical disc recording / reproducing apparatus 221 suitable is performed on the inserted optical disc 222.
  • the various parameters include adjusting the amplification factor of the amplifier included in the focus control unit 212 and the tracking control unit 215 in accordance with the reflectance of the optical disc 222.
  • the management information of the optical disc 222 is read in S404.
  • the timing of the adjustment process S403 is not limited to this, and part of the adjustment process may be performed after the management information read S404.
  • FIG. 29 shows a processing flow in the case where a recording command is sent to the optical disc recording / reproducing apparatus 221 in a state where recording or reproduction is possible.
  • the optical disc recording / reproducing apparatus 221 determines whether or not the OPC process is necessary when recording on the optical disc 222 currently inserted (S1202).
  • the OPC processing is necessary when, for example, the optical disc 222 is inserted into the optical disc recording / reproducing apparatus 221 and the optimum laser beam intensity for recording is not obtained for the inserted optical disc 222, such as when the first recording command is received. It is determined. If it is determined that the OPC process is necessary, an OPC process to be described later is performed to obtain an optimum recording laser beam intensity (S1203). Thereafter, a seek operation is performed to position the laser spot LSW and the laser spot LSg at the recording position (S1204). Thereafter, a recording process (S1205) is performed.
  • the recording process (S1204) will be described with reference to FIG.
  • FIG. 22 is an enlarged view of a part of the optical disk 222 having the structure shown in FIG.
  • FIG. 22 shows a state in which a recording light spot 500 is focused on the recording layer and a mark is recorded while proceeding in the tangential direction of the optical disk 222.
  • the tracking servo control light spot 501 and the light are recorded.
  • a spot 502 is placed at a certain distance in the radial direction from the light spot 500 and the optical disc 222, and is focused on the recorded mark and on the area where the mark is to be recorded (unrecorded area). It shows that the light spot 511 is condensed in the groove (track) of the guide layer substantially directly below the light spot 500.
  • the light spots 500, 501, and 502 are originally separated from the same light flux and emitted from the same objective lens 311 (not shown), and are described as laser spots LSW in FIG.
  • the light spot 511 is a light flux different from that of the light spots 500, 501, and 502, but indicates that the light spot 511 is emitted from the same objective lens 311, and is described as a laser spot LSg in FIG.
  • the optical disc recording / reproducing device 221 controls tracking so that the light spot 501 or the light spot 502 follows the recorded mark when a recorded mark exists in the recording layer, and determines the position of the light spot 500 in the disc radial direction. Then, the mark is recorded by changing the intensity of the laser beam of the light spot 500.
  • the light spot 511 is controlled so as to be positioned on the track of the guide layer, and by reading the wobble of the track, the relative speed between the light spot 500 and the optical disk 222 is obtained, thereby determining the length of the mark to be recorded. .
  • the recording operation ends (S1206). If it is determined that the OPC process is unnecessary, the seek operation (S1204) and the recording operation (S1295) are performed, and the recording operation ends (S1206).
  • FIG. 23 shows an example of a flowchart of the OPC operation.
  • the OPC operation is started S1601
  • the laser spot LSW may be moved to the OPC region of the designated layer to identify whether the recording mark row is detected from the reflected light. If it is the first OPC for the specified layer, it is positioned at the position of the first OPC (S1603).
  • the tracking control unit 215 outputs a signal for driving the tracking driving unit 216 based on the tracking error signal from the tracking error signal generating unit 210, and moves the objective lens 311. At this time, the tracking control unit 215 does not output the driving signal to the relay lens driving unit 219 or outputs a constant signal. Since the input to the relay lens driving means 219 is constant or not input, the radial direction of the relay lens 321 is not driven or is positioned at a fixed position. Thereafter, the first OPC operation S1604 is performed.
  • the operation of the OPC is, for example, by performing test recording while changing the intensity of the laser beam, and then reproducing the area where the test recording has been performed, and the optimum recording laser based on the change in the amplitude of the reproduction signal and the intensity of the laser beam at the time of the test recording
  • the optimum laser light intensity is obtained by calculating the light intensity.
  • a mark row is recorded S1605 in the OPC area with the intensity of the laser beam obtained by the previous OPC.
  • the mark row to be recorded has a pattern in which the recording mark row and the unrecorded portion for OPC alternate in one round.
  • the tracking control unit 215 outputs a signal for driving the tracking driving unit 216 based on the tracking error signal from the tracking error signal generating unit 210, and moves the objective lens 311. At this time, the tracking control unit 215 does not output the driving signal to the relay lens driving unit 219 or outputs a constant signal. Since the input to the relay lens driving means 219 is constant or not input, the radial direction of the relay lens 321 is not driven or is positioned at a fixed position. The current position at the time of recording is acquired from address information added to the guide layer.
  • the pattern method for performing recording with the optimum laser light intensity in the OPC area may be recorded so that tracking servo control can be performed by switching the light spot that generates the tracking error signal, as will be described later.
  • the optical disc recording / reproducing apparatus 221 having the light spot 501 and the light spot 502 on one track before and after the light spot 500 to be recorded, at least 3 tracks at any point are extracted from 3 consecutive tracks. If there is a mark row recorded with an optimum laser beam intensity for the track, stable tracking servo control can be performed in the OPC area, and N light beams having different distances from the recording light spot 500 in the radial direction of the optical disk 222. In the case of the optical disk 222 having spots, stable tracking servo control is possible if there is a mark row recorded with an optimum laser beam intensity for at least one continuous N track.
  • a rotation synchronization signal from the spindle motor 207 is used to switch a light spot that generates a tracking error signal when recording one mark per track for three tracks. But you can take the timing.
  • the circumferential length of an unrecorded track that does not generate a mark row with the optimum laser light intensity to be an integral multiple of the length used in OPC, all areas that cannot be used in test recording for OPC It can be recorded as a record mark row for tracking servo control.
  • the light spot that generates the tracking error signal becomes longer since the tracking error signal generated from both the light spot before and after the switching is approximately the same in the vicinity of the switching timing. It is possible to increase the time width during which switching is possible.
  • the mark row to be recorded is good because it is possible to detect the position of the light spot 500 that is currently recording / reproducing during tracking servo control of the OPC area by entering layer information and an address indicating the radial position. .
  • the current light spot 500 is in focus before track control is performed. It is good because the layer can be detected.
  • the recorded mark row is recorded not for recording information at a high density but for generating a tracking error signal that enables stable tracking servo control of the light spot 500, so that actual information is recorded. Unlike the mark row of the portion to be processed, if the mark row has a stable quality of the tracking error signal, stable tracking servo control may be possible.
  • the OPC operation ends (S1608). If the OPC for the specified layer of the inserted optical disk 222 is the second or later, the tracking servo is performed using the mark train recorded with the optimum recording laser light intensity already recorded in the OPC area. Control is performed, and an area usable for OPC is searched S1606.
  • FIG. 18 is a diagram illustrating three times during which the light spot 500, the light spot 501, and the light spot 502 are performing tracking servo control on the recording mark row in the OPC area. Time advances in the order of (a), (b), and (c), and the light spot 500, the light spot 501, and the light spot 502 advance from left to right as viewed in the figure.
  • tracking servo control is performed using the tracking error signal generated from the light spot 500.
  • the light spot that generates the tracking error signal is switched from the light spot 500 to the light spot 501 or the light spot 502, and tracking servo control is performed.
  • the light spot for generating the tracking error signal is switched from the light spot 501 or the light spot 502 to the light spot 500 to perform tracking servo control.
  • the light spot that generates the tracking error signal is switched using the tracking error signal selection means 1104 and tracking servo control is performed, so that the mark row is not recorded or the laser light intensity is optimized. It is possible to scan the light spot 500 while performing stable tracking servo control even on a track where there is a non-existing region.
  • the switching operation of the tracking error signal selection means 1104 may be performed based on position information read from a recorded mark row, for example.
  • the light spot that generates the tracking error signal may be switched when the signal amplitude from the mark row obtained from the light spot to be switched next becomes a certain value or more.
  • switching the light spot that generates the tracking error signal according to the pattern enables switching timing so that the switching timing can be grasped in advance. This is good because the process can be simplified.
  • the OPC operation is performed while performing the tracking servo control by performing the switching operation of the light spot that generates the tracking error signal (S1606).
  • the OPC operation here is characterized in that the OPC operation is performed by applying tracking servo control to the first OPC operation S1604 while switching the light spot that generates the tracking error signal.
  • OPC processing is performed while performing stable tracking servo control by performing tracking servo control with a light spot different from the light spot 500 where recording is actually performed, and performing the second and subsequent OPC operations. I can do it.
  • mark row recording S1605 is performed in the OPC area immediately after OPC recording.
  • the mark row recording S1605 can be performed in the OPC area at a relative angle similar to the relative angle between the optical disc 222 and the optical pickup 203 in the radial direction at the time of the first OPC operation S1604.
  • the mark row recording operation is performed before the optical disk 222 is taken out. For example, if OPC is performed as in the flowchart shown in FIG.
  • the OPC operation can be performed while performing stable tracking servo control even in the optical disc 222 in which the recording layer and the guide layer are separated.
  • the relative position in the radial direction between the laser spot LSg and the laser spot LSW is changed by driving the relay lens 321 so as to change the optical axis, but for example, the dichroic mirror 308 is provided.
  • the relative position in the radial direction between the laser spot LSg and the laser spot LSw focused on the optical disk 222 may be changed.
  • the relative position between the laser spot LSg and the laser spot LSw may be changed to a radius. If the direction can be changed, this embodiment can be implemented.
  • optical disc form The form of the optical disk 222 of the present embodiment is the same as that of the first embodiment.
  • optical disc recording / reproducing apparatus 221 of the present embodiment is the same as that of the third embodiment.
  • OPC process is different from the process described in the third embodiment.
  • FIG. 26 shows an example of a flowchart of the OPC operation.
  • the OPC operation is started (S901).
  • the laser spot LSW may be moved to the OPC region of the designated layer to identify whether the recording mark row is detected from the reflected light. If it is the first OPC for the specified layer, it is positioned at the position of the first OPC (S903). Thereafter, the first OPC operation is performed (S904).
  • the operation of OPC is shown in the third embodiment. Thereafter, the area used for OPC is overwritten (S905).
  • the intensity of the laser beam for overwriting is shown in FIG.
  • the operation of the OPC is performed by performing test recording by changing the intensity of the laser beam, and then reproducing the recorded area, and the optimum laser beam from the change due to the intensity of the laser beam at the time of trial recording with the amplitude of the reproduction signal Learning the intensity of. Therefore, there are marks recorded with a plurality of laser light intensities different from the optimum laser light intensity for trial recording in the area after OPC.
  • recording is performed with the intensity of the laser beam that can be recorded again on the area having the mark recorded by the trial recording.
  • the intensity of the laser beam when re-recording is the mark recorded with the laser beam intensity at which the tracking error signal generated from the record mark sequence after the overwrite process S905 is performed is in an optimum recording state. It is only necessary to be recorded so as to be equivalent to the tracking error signal generated from the column.
  • the signal amplitude of the entire mark can be changed by changing the recorded mark to be reproduced as a constant signal amplitude. It is good because it can be made constant. By doing so, it becomes possible to form a mark row recorded with a certain amplitude or more in the OPC area after recording, and to perform stable tracking servo control. At this time, if the pattern of the mark row to be overwritten is the same as the mark row recorded at the time of OPC, the signal amplitude of the mark row recorded by OPC can be increased.
  • the area usable for OPC is preferably increased.
  • an optical disk having a plurality of recording layers is targeted.
  • the optical disk does not necessarily have a structure having a plurality of recording layers.
  • it has a three-dimensional recording layer for volume recording. It may be an optical disk.
  • FIG. 30 is a block diagram showing an embodiment of an optical disc apparatus according to the present invention.
  • the optical disk apparatus records or reproduces information by irradiating an optical disk 331 mounted on the apparatus with laser light, and communicates with a host 330 such as a PC (Personal Computer) through an interface such as SATA (Serial Advanced Technology Attachment). .
  • a host 330 such as a PC (Personal Computer)
  • SATA Serial Advanced Technology Attachment
  • FIG. 31 shows the structure (cross section) of an optical disc targeted by this embodiment.
  • reference numeral 331 denotes an optical disc having one servo layer with grooves and one or more flat recording layers without grooves.
  • the groove of the servo layer is a spiral groove with the disk rotation axis as the center, similar to the groove found on a disk such as DVD or BD.
  • reference numeral 1211 in the figure is an objective lens for condensing a laser beam on the optical disk 331.
  • two different light beams pass through the objective lens 1211, one light beam is condensed on the servo layer of the optical disk 331, and the other light beam is applied to one of a plurality of recording layers of the optical disk 331. It shows that it is condensed.
  • the optical disk targeted by the present invention performs recording or reproduction using two or more light beams.
  • FIG. 32 is an enlarged view of a part of an optical disc having the structure shown in FIG.
  • the light spot 300 is focused on the recording layer and shows a state in which marks are recorded while proceeding in the tangential direction of the optical disk 331.
  • the light spot 301 and the light spot 302 are focused at a certain distance from the light spot 300 on the recorded mark and on the area where the mark is to be recorded (unrecorded area). Yes.
  • the light spot 311 is collected in the groove (track) of the servo layer substantially immediately below the light spot 300.
  • the light spots 300, 301, and 302 are originally separated from the same light flux and emitted from the same objective lens 1211, and the light spot 311 is different from the light spots 300, 301, and 302. However, it is shown that they were released from the same objective lens 1211 as those.
  • the distance between the light spot 300, the light spot 301, and the light spot 302 in the radial direction is adjusted by an optical element such as a grating 341 in FIG.
  • the distance in the circumferential direction may be a distance that can be resolved by the detector 1214.
  • the design of the track pitch in the radial direction of the light spot 300, the light spot 301, and the light spot 302 varies depending on the grating 341, the recording density, etc., 0.32um is shown as an example.
  • the laser beam is made up of three beams by the grating 341.
  • the two-beam method of the light spot 300 and the light spot 301 or a plurality of light beams can be used as long as the method follows the recording mark in the recording layer.
  • a system of a plurality of light beams such as five beams of secondary light, servo beam ⁇ primary light, servo beam ⁇ secondary light) is also conceivable.
  • the intensity of the light spot at the time of recording does not form a recording mark at the light spot 300 and does not overwrite the recording mark already recorded at the light spot 301.
  • the light intensity ratio of the light spot 301 to the light spot 300 to the light spot 302 is set to 1: 10: 1.
  • the intensity ratio of the spot is not limited to this.
  • a recording mark is not formed on the light spot 300 and a recording mark already recorded on the light spot 301 is not overwritten. Any intensity ratio may be used as long as no part is recorded.
  • (Configuration of optical disc apparatus of this embodiment) 30 includes an optical pickup 332, a signal processing circuit 333, a spindle motor 334, a servo error signal generation circuit 335, a recording / reproduction signal processing circuit 336, a spindle driving circuit 337, and an actuator driving circuit 338. , A relay lens drive circuit 339 and an aberration correction element drive circuit 340.
  • the signal processing circuit 333 is a circuit that performs various types of signal processing of the optical disk device, and operates with the potential Vref as a reference.
  • the signal processing circuit 333 includes a system control circuit 2301, a recording layer focus control circuit 2302, a switch 2303, an adder 2304, a recording layer focus drive voltage generation circuit 2305, a servo layer focus control circuit 2306, and a switch 2307.
  • the optical disk 331 is rotated at a predetermined rotational speed by the spindle motor 334.
  • the spindle motor 334 is controlled by a spindle control circuit 2313 that receives a command signal from a system control circuit 2301 mounted on the signal processing circuit 333.
  • the signal output from the spindle control circuit 2313 is amplified by the spindle drive circuit 337, and the amplified signal is supplied to the spindle motor 334.
  • the optical pickup 332 includes two optical systems having different wavelengths such as 405 nm and 650 nm.
  • the laser power control circuit 1201 is controlled by the system control circuit 2301 and outputs a current for driving the laser diode 1202. This driving current is applied with high frequency superposition of several hundred MHz in order to suppress laser noise.
  • the laser diode 1202 emits laser light having a wavelength of 405 nm with a waveform corresponding to the drive current.
  • the emitted laser light is converted into parallel light by the collimator lens 1203, partly reflected by the beam splitter 1204, and condensed on the power monitor 1206 by the condenser lens 1205.
  • the power monitor 1206 feeds back a current or voltage corresponding to the intensity of the laser light to the system control circuit 2301.
  • the intensity of the laser beam condensed on the recording layer of the optical disc 331 is maintained at a desired value such as 2 mW.
  • the laser light transmitted through the beam splitter 1204 is divided into three light beams (main beam zero-order light and its servo beam ⁇ primary light) corresponding to the light spots 300 to 302 shown in FIG. , And the convergence / divergence is controlled by the aberration correction element 1209 driven by the aberration correction element drive circuit 340 and transmitted through the dichroic mirror 1208.
  • the aberration correction element 1209 is controlled by the system control circuit 2301 through the aberration correction element drive circuit 340 so as to be at a predetermined position corresponding to the recording layer.
  • the dichroic mirror 1208 is an optical element that reflects light of a specific wavelength and transmits light of other wavelengths. Here, it is assumed that light having a wavelength of 405 nm is transmitted and light having a wavelength of 650 nm is reflected.
  • the laser beam that has passed through the dichroic mirror 1208 becomes circularly polarized light by the quarter-wave plate 1210 and is focused on the recording layer of the optical disc 331 by the objective lens 1211. The position of the objective lens 1211 is controlled by the actuator 1212.
  • the intensity of the laser light reflected by the optical disk 331 is modulated according to the information recorded on the optical disk 331, becomes linearly polarized light by the quarter-wave plate 1210, passes through the dichroic mirror 1208 and the aberration correction element 1209, and then is polarized beam splitter. 1207 is transmitted.
  • the transmitted laser light is condensed on the detector 1214 by the condenser lens 1213.
  • the detector 1214 detects the intensity of the laser beam and outputs a signal corresponding to the intensity to the servo error signal generation circuit 335 and the recording / reproduction signal processing circuit 336.
  • the laser power control circuit 1201 drives the laser diode 1215, and the laser diode 1215 emits laser light having a wavelength of 650 nm.
  • a part of the laser light passes through a collimator lens 1216, a beam splitter 1217, and a condenser lens 1218, and the power is monitored by a power monitor 1219.
  • the intensity of the laser beam condensed on the servo layer of the optical disc 331 is maintained at a desired power, such as 3 mW.
  • the laser light that has passed through the beam splitter 1217 passes through the polarization beam splitter 1220 and enters the relay lens 1221.
  • the relay lens 1221 is driven by an actuator 1228 to control the position of the light spot irradiated to the servo layer in the focus direction and the tracking direction.
  • the laser light that has passed through the relay lens 1221 is reflected by the dichroic mirror 1208, passes through the quarter-wave plate 1210, and is condensed on the servo layer of the optical disc 101 by the objective lens 1211.
  • the laser beam reflected by the optical disc 101 is reflected by the polarization beam splitter 1220 and condensed on the detector 1223 by the condenser lens 1222.
  • the actual relay lens 1221 is composed of a movable lens and a fixed lens, and only the movable lens is shown here).
  • the detector 1223 detects the intensity of the laser beam, and outputs a signal corresponding to the servo error signal generation circuit 335 and The data is output to the recording / reproducing signal processing circuit 336.
  • the recording / reproducing signal processing circuit 336 information read from the recording layer of the optical disc 331 (recorded data, current address information, etc.) is processed by performing processing such as amplification, equalization, and decoding on the signal detected by the detector 1214. Is output to the system control circuit 2301.
  • a clock signal serving as a reference for recording or reproduction is generated from a signal detected by the detector 1223 by a signal corresponding to a track formed by wobbling the servo layer, and the servo that the light spot 311 follows is generated.
  • the address corresponding to the position on the layer is reproduced and output to the system control circuit 2301.
  • Fig. 33 shows the configuration of the servo error signal generation circuit.
  • the signal output from the detector 1223 is input to the servo layer focus error signal generation circuit 1051 and the servo layer tracking error signal generation circuit 1052.
  • the servo layer focus error signal generation circuit 1051 generates a servo layer focus error signal (hereinafter referred to as S_FE) for use in focus control on the servo layer, and the servo layer tracking error signal generation circuit 1052 generates a light spot from the servo layer track.
  • a servo layer tracking error signal (hereinafter referred to as S_TE) representing the 311 position deviation is generated and output.
  • the signal output from the detector 1214 is input to the recording layer focus error signal generation circuit 1053 and the recording layer tracking error signal generation circuit 1054.
  • the recording layer focus error signal generation circuit 1053 generates a recording layer focus error signal (hereinafter referred to as R_FE) for use in focus control for the recording layer, and the recording layer tracking error signal generation circuit 1054 includes a recording mark row of the recording layer.
  • a recording layer tracking error signal (hereinafter referred to as R_TE) representing the positional deviation between the track and the light spot is generated and output. Further, the difference between the servo layer tracking error signal S_TE and the recording layer tracking error signal R_TE is calculated by the subtracting circuit 1055, and the relative position shift in the tracking direction between the light spot on the servo layer and the light spot on the recording layer is calculated.
  • a relative position detection signal (hereinafter referred to as TE) is output.
  • an F_SUM signal corresponding to the total reflected light amount of the light spot 302 is generated from the signal detected by the detector 1214 by the total light amount detection circuit 1056, and an R_SUM signal corresponding to the total reflected light amount of the light spot 301 is generated by the total light amount detection circuit 1057. Generate and output. Here, each error signal is output with reference to the potential Vref.
  • Focus control and tracking control performed on the recording layer (any one of the recording layers) in the 405 nm optical system will be described.
  • the recording layer focus control circuit 2302 performs gain and phase compensation for the recording layer focus error signal R_FE in response to a command signal from the system control circuit 2301, and outputs a drive signal for performing focus control on the recording layer.
  • the drive signal output from the recording layer focus control circuit 2302 is input to the actuator drive circuit 338 via the switch 2303 and the adder 2304.
  • the switch 2303 selects and outputs the output signal of the recording layer focus control circuit 2302 or the reference potential Vref based on the R_FON signal output from the system control circuit 2301.
  • a is selected as the terminal of the switch 2303, and the output signal of the recording layer focus control circuit 2302 is output to the actuator drive circuit 338 via the adder 2304.
  • the switch 2303 selects the terminal b and outputs the reference potential Vref.
  • the R_FON signal is a signal for instructing on / off of focus control for the recording layer.
  • a switch 2303 functions as a switch for switching on and off the focus control for the recording layer.
  • the focus control for the recording layer is turned on. This operation is called a focus pull-in operation.
  • the recording layer focus drive voltage generation circuit 2305 outputs a predetermined voltage in response to a command signal from the system control circuit 2301.
  • the recording layer focus drive voltage generation circuit 2305 outputs, for example, a sweep voltage in a focus sweep operation and a jump voltage at the time of a focus jump.
  • the output signal of the recording layer focus drive voltage generation circuit 2305 and the output signal of the switch 2303 are added by the adder 2304 and output to the actuator drive circuit 338 as R_FOD.
  • the objective lens 1211 By driving the actuator 1212 in a direction perpendicular to the disk surface in accordance with the R_FOD signal, the objective lens 1211 is driven in the focus direction. Thereby, the recording layer focus control is performed so that the light spot 300 is focused on the recording layer. Next, the tracking control of the recording layer in this embodiment will be described.
  • Servo layer tracking error signal S_TE and recording layer tracking error signal R_TE are input to tracking control circuit 2310 from servo error signal generation circuit 335.
  • tracking control is performed based on the recording layer tracking error signal R_TE detected from the track formed of the mark row recorded on the recording layer. Therefore, the recording layer tracking error signal R_TE is compensated for gain and phase by a command signal from the system control circuit 2301, and a driving signal for performing tracking control is output.
  • the drive signal output from the tracking control circuit 2310 is input to the actuator drive circuit 338 via the switch 2311.
  • the switch 1311 selects the output signal of the tracking control circuit 2310 or the reference potential Vref based on the TRON signal output from the system control circuit 2301, and outputs it to the actuator drive circuit 338 as the tracking drive signal TRD.
  • e is selected as the terminal of the switch 1311, and an output signal of the tracking control circuit 2310 is output to the actuator drive circuit 338.
  • the switch 2311 selects the terminal f and outputs the reference potential Vref.
  • the TRON signal is a signal for instructing on / off of the tracking control.
  • the switch 2311 functions as a switch for switching tracking control on and off. Tracking control is turned on when the TRON signal is switched from Low to High, and this operation is called a track pull-in operation.
  • the actuator driving unit 338 drives the actuator 1212 in accordance with the output signal of the tracking control circuit 2310, so that the track formed of the mark row recorded on the recording layer is the light spot. Tracking control is performed so that 300 follows.
  • Focus control and tracking control performed on the servo layer in the 650 nm optical system will be described.
  • the servo layer focus control circuit 2306 compensates the servo layer focus error signal S_FE for gain and phase in response to a command signal from the system control circuit 2301, outputs a drive signal for performing focus control on the servo layer, and switches 2307, and input to the relay lens lens driving circuit 339 via the adder 2308. Thereby, the focus control for the servo layer is performed.
  • the switch 2307 selects and outputs the output signal of the servo layer focus control circuit 2306 or the reference potential Vref based on the S_FON signal output from the system control circuit 2301.
  • c is selected as the terminal of the switch 2307.
  • the switch 2307 selects the terminal d and outputs the reference potential Vref.
  • the S_FON signal is a signal for instructing on / off of focus control for the servo layer.
  • the switch 2307 functions as a switch for switching on / off the focus control for the servo layer.
  • the focus control for the servo layer is turned on, and this operation is called a focus pull-in operation.
  • the servo layer focus drive voltage generation circuit 2309 outputs a predetermined voltage in response to a command signal from the system control circuit 2301. For example, the servo layer focus drive voltage generation circuit 2309 outputs a sweep voltage in the focus sweep operation.
  • the output signal of the servo layer focus drive voltage generation circuit 2309 and the output signal of the switch 2307 are added by the adder 2308 and output to the relay lens drive circuit 339 as S_FOD.
  • the relay lens driving circuit 339 drives the actuator 1228 mounted in the optical pickup 332 according to the S_FOD signal.
  • the focus control on the servo layer is performed so that the light spot with a wavelength of 650 nm irradiated on the optical disc 331 by this driving is always focused on the surface of the servo layer of the optical disc 331.
  • the tracking error signal cannot be detected from the track formed of the mark row recorded on the recording layer, so that the servo layer tracking error signal S_TE obtained from the track formed on the servo layer is detected. Based on the tracking control. Therefore, in response to a command signal from the system control circuit 2301, gain and phase compensation is performed on the servo layer tracking error signal S_TE input from the servo error signal generation circuit 335, and a drive signal for performing tracking control is output. To do.
  • the drive signal output from the tracking control circuit 2310 is input to the actuator drive circuit 338 via the switch 2311.
  • the switch 2311 selects the output signal of the tracking control circuit 2310 or the reference potential Vref based on the TRON signal output from the system control circuit 2301, and outputs it to the actuator drive circuit 108 as the tracking drive signal S_TRD.
  • the switch 2311 selects the terminal f and outputs the reference potential Vref.
  • the actuator driving circuit 338 drives the actuator 1212 according to the output signal of the tracking control circuit 2310 so that the light spot 311 follows the track of the servo layer. Control is done Next, the relative position control in the present embodiment will be described. A method for generating the relative position detection signal TE which is a signal for the relative position control will be described. In recording information, in order to record a record mark row at a constant track pitch interval, it is necessary to control to maintain the relative relationship between the optical spots of the light spot having a wavelength of 405 nm and the light spot having a wavelength of 650 nm.
  • the servo layer tracking error signal S_TE representing the positional deviation of the light spot 311 from the track of the servo layer
  • the recording layer tracking error signal R_TE representing the positional deviation of the light spot 301 from the track formed of the recording mark row of the recording layer.
  • a servo layer tracking error signal S_TE, a recording layer tracking error signal R_TE, and a relative position detection signal TE that is the difference between the servo layer tracking error signal S_TE and a servo error signal generation circuit 335 are generated.
  • the servo layer tracking error signal S_TE is a signal when following the track of the servo layer, it is used as the reference axis of the optical axis. Since the error from the reference axis is caused by the tilt of the disk, etc., the relative relationship between the two optical axes can be maintained by using the error from the reference axis as the control input to the actuator 1228 of the relay lens 1221. Therefore, it is possible to suppress overwriting in the recorded area.
  • the relative position control circuit 2312 performs gain and phase compensation on the relative position detection signal TE in response to a command signal from the system control circuit 2301, and outputs a signal for performing relative position control.
  • a signal output from the relative position control circuit 2312 is input to the relay lens driving circuit 339 via the switch 2314.
  • the switch 2314 selects the output signal of the relative position control circuit 2312 or the reference potential Vref based on the TLON signal output from the system control circuit 2301, and becomes an input of the relay lens drive circuit 339 as the relative position control drive signal TLD.
  • g is selected as the terminal of the switch 1314, and the output signal of the relative position detection circuit 2312 becomes the input of the relay lens driving circuit 339.
  • the switch 2314 selects the terminal h and outputs the reference potential Vref.
  • the TLON signal is a signal for instructing on / off of relative position control with respect to the recording layer.
  • the switch 2314 functions as a switch for switching on / off the relative position control with respect to the recording layer.
  • the relative position control is turned on when the TLON signal is switched from Low to High.
  • the optical axis of 650 nm changes according to the relative position control driving signal TLD.
  • the light spot 311 irradiated to the servo layer is displaced in the track direction, and the servo layer tracking error signal S_TE changes.
  • the servo layer tracking control system drives the actuator 1212 of the objective lens 1211 so that the light spot 311 follows the track of the servo layer.
  • the frequency band limitation of the relative position detection signal TE may be performed using a low-pass filter, or the frequency response characteristic of the actuator 1228 of the relay lens 1221 may be made lower than the frequency response characteristic of the actuator 1212 of the objective lens 1211.
  • FIG. 34 is a conceptual diagram of the relative position detection signal TE.
  • a case where the servo layer tracking error signal S_TE and the recording layer tracking error signal R_TE have the same frequency and amplitude is illustrated.
  • the positive side of the servo layer tracking error signal S_TE, the recording layer tracking error signal R_TE, and the relative position detection signal TE is the inner circumferential direction, and the negative side is the outer circumferential direction.
  • FIG. 34A illustrates a case where the recording layer tracking error signal R_TE has an offset of Va from the reference voltage Vref.
  • the recording layer tracking error signal R_TE indicates that the light spot 301 is displaced from the center of the mark row.
  • both the servo layer tracking error signal S_TE and the recording layer tracking error signal R_TE operate near the reference voltage Vref, and are centered on the servo groove of the servo layer and the mark row of the recording layer. It can be made to follow.
  • FIG. 35 is a flowchart showing an outline of the operation of the optical disk apparatus of the present embodiment.
  • setup processing is performed in step S6602.
  • various processes such as disc recognition, focus pull-in, tracking pull-in, aberration adjustment, and reproduction of management information on the disc 331 are performed to make it possible to record or reproduce information.
  • step S6604 when a data reproduction command is received from the host 330 in step S6603, data reproduction processing is performed in step S6604.
  • a data recording command is received from the host 330 in step S6605
  • a data recording process is performed in step S6606.
  • another command is received from the host computer in step S6607, other processing is performed in step S6610. If the optical disk is ejected in step S6609, the process is terminated.
  • step S7701 a focus jump is performed to move a 405 nm light spot to the recording layer n to be recorded.
  • step S7702 tracking control based on the servo layer tracking error signal S_TE obtained from the track formed on the servo layer is turned on.
  • step S7703 it is determined whether the recording layer that has moved is in an unrecorded state. As a method for determining whether or not it is in an unrecorded state, for example, there is a method performed based on disc management information acquired in the setup process S6602.
  • step S7703 If it is determined in step S7703 that it is not unrecorded, based on the servo layer tracking error signal S_TE detected from the track of the servo layer and the recording layer tracking error signal R_TE detected from the track formed of the mark row recorded on the recording layer.
  • the relative position control by the relative position detection signal TE generated in this way is turned on, the position of the 650 nm light spot irradiated on the servo layer and the relative position of the 405 nm light spot irradiated on the recording layer are held, and the servo Control is performed so that the light spot 311 follows the track of the layer.
  • the system control circuit 2301 sets a recording start address, recording data, and the like in the recording / reproducing signal processing circuit 336, and recording starts from the recording start address in step S7706.
  • the recording / reproducing signal processing circuit 336 modulates the input data and address information by a predetermined method based on the reference clock signal generated from the signal reproduced from the servo layer, and outputs the modulated data and address information to the laser power control circuit 1201.
  • the laser power control circuit 1201 outputs a drive current corresponding to the output of the recording / reproducing signal processing circuit 336 to the laser diode 1202, and the laser diode 1202 emits laser light with a corresponding intensity, whereby recording is performed on the recording layer of the optical disc 331. Done.
  • step S7706 the recording process is terminated when it coincides with the recording end address.
  • Determination of the unrecorded state in step S7703 can also be performed based on the amplitude of the recording layer tracking error signal R_TE.
  • the recording layer tracking error signal R_TE changes according to the deviation between the light spot 301 and the track formed by the mark row recorded in the recording layer, but in the unrecorded state, the reference voltage It is near Vref. Accordingly, a focus jump is performed on the recording layer n in step S7701, and the unrecorded state can be determined based on the amplitude of the recording layer tracking error signal R_TE in a state where the tracking control is turned off.
  • the light spot 301 and the light spot 301 irradiated on the recording layer are normally recorded at a predetermined track interval while the light spot 301 follows a track made up of recorded mark rows during recording. It can be confirmed.
  • the total reflection of the light spot 302 that has not been recorded compared to the R_SUM signal corresponding to the total reflected light amount of the light spot 301 that follows the recording mark.
  • the signal level of the F_SUM signal corresponding to the amount of light increases.
  • the recording state is normal, and when the R_SUM signal amplitude is larger than the F_SUM signal amplitude, the recording state is abnormal and recording is stopped. Can do. If the reflectance increases when the recording mark is formed on the optical disc 101, the magnitudes of the amplitudes of the F_SUM signal and the R_SUM signal are reversed.
  • the position of the light spot 301 and the light spot 311 following the recording mark can be read as an address by the recording / reproducing signal processing circuit 336, this address is recorded at an appropriate position and an appropriate recording layer. It may be used to check if it is being performed.
  • a recording layer tracking error signal R_TE is generated at the light spot 301 because a track including a recording mark row is formed when recording is performed once or more times on the disc. It becomes possible. Therefore, the relative position control may be turned on at the time when one or more rotations are recorded after the start of recording. Alternatively, recording may be stopped and recording may be started again after the relative position control is turned on.
  • step S7701 after performing the focus jump in step S7701, only the focus control is turned on and the relative position control is turned off in the recording layer. However, if there is no recording mark, the recording layer tracking error signal R_TE is near Vref. Turning on position control has no effect. Therefore, when the relative position control is turned on and a recording mark is formed, it is possible to generate R_TE from the recording mark and cause the light spot 301 to follow the recording mark by the relative position control.
  • the servo layer is an example in which focus control and tracking control are performed by one beam.
  • a grating is provided between the beam splitter 1217 and the deflecting beam splitter 1220 to provide three beams (main beam 0th order). Light and its servo beam ⁇ primary light).
  • the signal generated by the servo error signal generation circuit 105 is a differential push-pull method (DPP method) or push-pull method if it is a tracking signal, and a knife-edge method or differential astigmatism if it is a focus signal.
  • DPP method differential push-pull method
  • a method such as a method may be used.
  • the above-described method is not limited and may be a different method.
  • the feature of this embodiment is that when a recorded mark exists in the recording layer, the light spot 311 irradiated to the servo layer follows the track of the servo layer, and the light spot 301 follows the recorded mark row.
  • the relative position in the track direction of the 650 nm light spot irradiated on the servo layer and the 405 nm light spot irradiated on the recording layer is maintained, and recording is performed at a predetermined track interval. Is possible. Thereby, it is possible to suppress overwriting the previously recorded data even when the relative angle between the laser beam and the optical disk changes from the previous recording due to temperature, the chucking state of the optical disk, etc. during additional recording, Additional recording can be performed without providing a useless area.
  • a reference clock signal or the like can be generated from information obtained from the servo layer track even during recording.
  • FIG. 37 shows an example of an optical disk apparatus for performing relative position control according to the present embodiment.
  • the optical pickup 332 is provided with a variable angle rising mirror 1227 and the relative position control is realized by the optical axis angle variable element driving circuit 342. Further, the description overlapping with the contents described in the fifth embodiment is omitted.
  • (Means for realizing the present embodiment) 37 includes an optical pickup 332, a signal processing circuit 333, a spindle motor 334, a servo error signal generation circuit 335, a recording / reproduction signal processing circuit 336, a spindle driving circuit 337, and an actuator driving circuit 338. , A relay lens driving circuit 339, an aberration correction element driving circuit 340, and an optical axis angle variable element driving circuit 342.
  • the laser power control circuit 1201 is controlled by the system control circuit 2301 and outputs a current for driving the laser diode 1202. This driving current is applied with high frequency superposition of several hundred MHz in order to suppress laser noise.
  • the laser diode 1202 emits laser light having a wavelength of 405 nm with a waveform corresponding to the drive current.
  • the emitted laser light is converted into parallel light by the collimator lens 1203, partly reflected by the beam splitter 1204, and condensed on the power monitor 1206 by the condenser lens 1205.
  • the laser light transmitted through the beam splitter 1204 is converted into a plurality of light beams (main beam 0th order light and its servo beam ⁇ 1st order light) by the grating 341 of the three beam specification, reflected by the polarization beam splitter 1207, and corrected for aberration.
  • Convergence / divergence is controlled by the aberration correction element 1209 driven by the element driving circuit 110, and passes through the dichroic mirror 1208.
  • the dichroic mirror 1208 is an optical element that reflects light of a specific wavelength and transmits light of other wavelengths. Here, it is assumed that light having a wavelength of 405 nm is transmitted and light having a wavelength of 650 nm is reflected.
  • variable angle rising mirror 1227 is a variable angle rising mirror that can change the optical axis direction of reflected light by changing the angle of the mirror.
  • the position of the objective lens 1211 is controlled by the actuator 1212.
  • the intensity of the laser light reflected by the optical disk 331 is modulated according to the information recorded on the optical disk 331, becomes linearly polarized light by the quarter-wave plate 1210, is reflected by the angle-variable rising mirror 1227, and is reflected by the dichroic mirror 1208 and aberration.
  • the light passes through the correction element 1209 and passes through the polarization beam splitter 1207.
  • the transmitted laser light is condensed on the detector 1214 by the condenser lens 1213.
  • the detector 1214 detects the intensity of the laser beam and outputs a signal corresponding to the intensity to the servo error signal generation circuit 335 and the recording / reproduction signal processing circuit 336.
  • the laser power control circuit 1201 drives the laser diode 1215, and the laser diode 1215 emits laser light having a wavelength of 650 nm.
  • a part of the laser light passes through a collimator lens 1216, a beam splitter 1217, and a condenser lens 1218, and the power is monitored by a power monitor 1219.
  • the laser light that has passed through the beam splitter 1217 passes through the polarization beam splitter 1220 and enters the relay lens 1221.
  • the relay lens 1221 is driven by an actuator 1228 to control the position of the light spot irradiated on the servo layer in the focus direction.
  • the laser light that has passed through the relay lens 1221 is reflected by the dichroic mirror 1208 and the variable angle raising mirror 1227, passes through the quarter-wave plate 1210, and is condensed on the servo layer of the optical disk 331 by the objective lens 1211.
  • the laser beam reflected by the optical disk 331 is reflected by the polarization beam splitter 1220 and condensed on the detector 1223 by the condenser lens 1222.
  • the detector 1223 detects the intensity of the laser beam and outputs a signal corresponding to the intensity to the servo error signal generation circuit 335 and the recording / reproduction signal processing circuit 336.
  • the relative position control in this embodiment will be described.
  • the servo layer tracking error signal S_TE is a signal when following the track of the servo layer, it is used as the reference axis of the optical axis.
  • the error from the reference axis is caused by the tilt of the disk or the like, the error from the reference axis is input to the optical axis angle variable element drive circuit 342 and the angle of the mirror is changed by controlling the angle variable raising mirror 1227. Then, control is performed to minimize this error. As a result, since the relative relationship of the optical axes can be maintained, overwriting in the recorded area can be suppressed.
  • the relative position detection circuit 2312 compensates the relative position detection signal TE for gain and phase in response to a command signal from the system control circuit 2301, and outputs a drive signal for performing relative position control.
  • the drive signal TLD output from the relative position detection circuit 2312 is input to the optical angle variable element drive circuit 112 via the switch 2314.
  • the variable angle rising mirror 1227 is driven by the optical angle variable element driving circuit 112
  • the optical axes of 405 nm and 650 nm change. This change in the optical axis also becomes a displacement of the servo layer tracking error signal S_TE.
  • the actuator 1212 of the objective lens 1211 is driven by the servo layer tracking control system, the light spot 311 operates so as to follow the track of the servo layer. As a result, the relative relationship between the optical axes of 405 nm and 650 nm can be maintained.
  • the switch 2314 selects the output signal of the relative position detection circuit 2312 or the reference potential Vref based on the TON signal output from the system control circuit 2301, and outputs the selected signal as a TLD to the optical angle variable element driving circuit 342.
  • the relative position control is turned on and the variable angle rising mirror 1227 is driven by the variable optical axis angle element driving circuit 342
  • the relative relationship between the optical axes of 405 nm and 650 nm changes.
  • the light spot 311 irradiated to the servo layer is displaced in the track direction, and the servo layer tracking error signal S_TE changes.
  • the servo layer tracking control system drives the actuator 1212 of the objective lens 1211 so that the light spot 311 follows the track of the servo layer. Therefore, in order to suppress the deviation of the light spot 311 in the track direction due to the relative position control, it is necessary to make the control band of the relative position control system lower than the control band of the servo layer tracking control system. For this reason, for example, the frequency band of the relative position detection signal TE may be limited by a low-pass filter, or the frequency response characteristic of the variable angle raising mirror 1227 may be made lower than the frequency response characteristic of the actuator 1212 of the objective lens 1211.
  • the variable raising mirror 1227 is controlled. In this case, since it is offset in the inner circumferential direction, the variable angle raising mirror 1227 is driven counterclockwise corresponding to the outer circumferential direction by an angle corresponding to Va. This cancels the offset.
  • the operation of the optical axis variable element 1227 at this time is schematically shown in FIG. FIG. 38 shows a part of the optical pickup 332 of FIG.
  • the 650 nm laser beam and the 405 nm laser beam have the same optical path in the dichroic mirror 1208, and the optical axis direction of the reflected light changes according to the angle of the variable angle raising mirror 1227.
  • the angle variable raising mirror 1227 rotates counterclockwise as shown in FIGS. 38 (a) to 38 (b), so that light of 405 nm and 650 nm can be obtained. Adjust the axis. As a result, as shown in FIG.
  • both the servo layer tracking error signal S_TE and the recording layer tracking error signal R_TE operate in the vicinity of the reference voltage Vref, and follow the center of the servo layer track and the mark layer of the recording layer. Can be in a state of being.
  • the relative position is controlled by driving the relay lens 1221 in the track direction by the actuator 1228, and the relative relationship between the optical axis of the light spot having the wavelength of 405 nm and the light spot having the wavelength of 650 nm is maintained.
  • This embodiment is different from the embodiment in that it is realized not by the actuator 1228 of the relay lens 1221 but by the variable angle raising mirror 1227.
  • the optical axis of the two laser beams is caused by warpage due to aging of the optical disc or differences in recording devices. Even if there is tilt on the optical disc, it is possible to suppress overwriting in the recorded area.
  • the optical disc can be recorded even if the optical disc is tilted with respect to the optical axes of the two laser beams generated by the warpage of the optical disc and the deviation between the recording layer and the servo layer. It is possible to suppress overwriting recording in a completed area.
  • a variable angle rising mirror 1227 is mounted as an optical axis angle variable element, and both the optical axes of 405 nm and 650 nm are adjusted.
  • the variable angle rising mirror 1227 may be disposed at a position where only one of the optical axes of 405 nm and 650 nm can be adjusted.
  • the variable angle raising mirror for example, a galvano mirror or a MEMS (Micro Electro Mechanical Systems) mirror can be used.
  • the angle of the variable angle rising mirror 1227 is changed in accordance with the change amount to change the beam incident angle to the disk.
  • the recorded mark can be scanned, so that a stable erase operation and rewrite operation can be performed on a rewritable disc. Further, at the time of additional recording, new information can be continuously recorded from the recorded area without providing a useless area.
  • an optical disk apparatus corresponding to a grooveless disk composed of a servo layer having a physical groove structure and a plurality of recording layers having no physical groove structure such as a land / groove structure has been described.
  • it also supports micro-holograms that record while changing the focal position in the depth direction on a servo layer with a groove structure and a recording layer that does not have a layer structure, or volume recording optical disks that use principles such as two-photon absorption It is possible.
  • the recording layer tracking error signal is detected based on the amount of reflected light from the track consisting of the mark row recorded on the recording layer, and the servo layer tracking error signal generated based on the amount of reflected light from the track of the servo layer is used. By detecting the relative position, it is possible to deal with the same as a grooveless disk.
  • FIG. 39 shows a case different from FIG. 39, since the objective lens 1211 is controlled based on the displacement of the servo layer tracking error signal S_TE, the disc tilt of the disc 101 and the eccentricity of the disc are suppressed. However, the recording layer tracking error signal R_TE is displaced in synchronism with one rotation period of the disk as shown in FIG. In this case, a TE that cancels a component that changes in one rotation period of the disk is generated from the servo error signal generation circuit 335. Thus, TE may be a signal that does not change with time or a signal that changes. Furthermore, the frequency and amplitude of the servo layer tracking error signal S_TE and the recording layer tracking error signal R_TE do not need to match.
  • this invention is not limited to the above-mentioned Example, Various modifications are included.
  • the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described.
  • a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment.
  • each of the above-described configurations may be configured such that a part or all of the configuration is configured by hardware, or is realized by executing a program by a processor.
  • control lines and information lines indicate what is considered necessary for the explanation, and not all the control lines and information lines on the product are necessarily shown. Actually, it may be considered that almost all the components are connected to each other.
  • Aberration correction element 1310 ... 1/4 wavelength plate 1311 ... Objective lens 1312 ... Actuator 1313 ... Condensing lens 1314 ... Detec 1315: Laser diode 1316 ... Collimator lens 1317 ... Beam splitter 1318 ... Condensing lens 1319 ... Power monitor 1320 ... Polarizing beam splitter 1321 ... Relay lens 1322 ... Condensing lens 1323 ... Detector 1324 ... Detector 1401 ... Recording layer Sub tracking error signal generation Circuit 1402 ... Recording layer Main tracking error signal generation circuit 1403 ... Servo layer tracking error signal generation circuit 1404 ... Recording layer focus error signal generation circuit 1405 ... Servo layer focus error signal generation circuit 1501 ... System control circuit 1502 ...
  • MainTE signal monitor circuit 221 Optical disk recording / playback device 222 Optical disc 500 light spot 501 light spot 502 Light spot 511 Light spot 1101 Front SUB tracking error signal generation means 1102 Main tracking error signal generation means 1103 Post SUB tracking error signal generation means 1104 Tracking error signal selection means 331 ... optical disk 332 ... optical pickup 333 ... signal processing circuit 334 ... spindle motor 335 ... servo error signal generation circuit 336 ... recording / reproduction signal processing circuit 338 ... actuator drive circuit 339 ... relay lens drive circuit 340 ... aberration Correction element drive circuit 341 ... Grating 342 ... Optical axis angle variable element drive circuit 1202 ... Laser diode 1209 ... Aberration correction element 1211 ... Objective lens 1212 ... Actuator 1221 ... Relay lens 1227 ... Variable angle rising mirror 1228 ... Actuator 2301 ... System control Circuit 2310 ... Tracking control circuit 2312 ... Relative position control circuit

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  • Optical Recording Or Reproduction (AREA)

Abstract

In order to appropriately perform additional recording on an optical disk having a servo layer and a recording layer, an optical disk device for recording information on an optical disk including one or more recording layers laminated in a film thickness direction is provided with an optical system for irradiating the recording layer with a first laser spot and a second laser spot, and performs track pitch adjustment for adjusting the spacing in the radial direction between mark rows formed in the recording layer when recording information by forming marks using the second laser spot while performing tracking using the first laser spot.

Description

光ディスク装置Optical disk device
　本発明は、レーザを用いて光ディスクから情報を再生、または光ディスクに情報を記録する光ディスク装置に関する。 The present invention relates to an optical disc apparatus for reproducing information from an optical disc using a laser or recording information on the optical disc.
　近年、Ｂｌｕ－ｒａｙ　Ｄｉｓｃ（ＴＭ）規格の光ディスクにおいて、従来の１層、２層に加えて、３層や４層の記録層を有する光ディスクが開発され規格化済みである。今後更なる大容量化を目指し、更なる記録層を有する光ディスクの開発が行われると予想されるが、物理的な溝構造を持つ層を多数、積層していくことはディスクの製造上、困難なことであった。そこで、記録層を多数、積層する場合でも製造が容易となるように、アドレッシング、トラッキングサーボ制御を行うためのアドレスを含む物理的な溝構造を持つ層（以下、サーボ層）を設け、ランド・グルーブ構造と言った物理的な溝構造を持たない記録再生を行う層（以下、記録層）からなる光ディスクが特許文献１で提案されている。このように記録再生を行う層が物理的な溝構造を持たない光ディスクを、以下、グルーブレスディスクと称する。また、特許文献１には、「ガイドトラックに追従しながら記録を行った後、ディスクの経時変化による反りや装置への脱着によって照射ビームの光軸に対するディスクの傾斜状態が変わってしまった場合、ガイドトラックに追従しながら追加記録を行うと、図２(b)に示すように記録済みの記録トラックと追加記録時の記録トラックとの間にずれが生じてしまう。このような記録トラックずれは、トラックピッチむらの原因となり、再生性能の劣化を引き起こすだけでなく、記録済み領域の記録情報に重ねて情報を記録してしまい、記録済み領域の記録情報を破壊してしまう可能性があるという問題があった。」との記載がある。さらに特許文献１の要約には、「ガイド層分離型の光記録媒体の記録層における記録済みの領域に続く追記開始位置を検出し、追加記録開始時に追記開始位置から未記録領域側に離れた位置に対向するガイドトラック上の位置にサーボ用の第１レーザビームの照射スポットを移動させることにより記録又は再生用の第２レーザビームの記録層への照射スポットを追従移動させ、その移動後の第２レーザビームの照射スポット位置から記録層への追加記録を開始する。」と記載されている。 In recent years, in the Blu-ray Disc (TM) standard optical disc, an optical disc having three or four recording layers has been developed and standardized in addition to the conventional one layer and two layers. In the future, it is expected that an optical disc having a further recording layer will be developed with the aim of further increasing the capacity, but it is difficult to manufacture a large number of layers having a physical groove structure in terms of manufacturing the disc. It was a thing. Therefore, in order to facilitate manufacturing even when a large number of recording layers are stacked, a layer having a physical groove structure (hereinafter referred to as a servo layer) including addresses for addressing and tracking servo control is provided. Patent Document 1 proposes an optical disc composed of a layer (hereinafter referred to as a recording layer) that performs recording and reproduction without a physical groove structure called a groove structure. An optical disc in which the recording / reproducing layer does not have a physical groove structure is hereinafter referred to as a grooveless disc. Further, Patent Document 1 states that, “After recording while following the guide track, the tilt state of the disc with respect to the optical axis of the irradiation beam has changed due to warpage due to the change of the disc over time or attachment to the device. When additional recording is performed while following the guide track, a deviation occurs between the recorded recording track and the recording track at the time of additional recording, as shown in FIG. In addition to causing track pitch unevenness and causing deterioration in reproduction performance, the information recorded on the recorded information in the recorded area may be destroyed and the recorded information in the recorded area may be destroyed. There was a problem. " Further, the summary of Patent Document 1 states that “the additional recording start position following the recorded area in the recording layer of the guide layer separation type optical recording medium is detected and separated from the additional recording start position to the unrecorded area side at the start of additional recording. By moving the irradiation spot of the first laser beam for servo to a position on the guide track opposite to the position, the irradiation spot on the recording layer of the second laser beam for recording or reproduction is moved to follow, and after the movement, “Additional recording on the recording layer is started from the irradiation spot position of the second laser beam”.
　特許文献２では、「円盤状光記録媒体上に少なくとも第１の光スポットと第２の光スポットを照射し第１の光スポットを用いてトラッキングを行いながら第２のスポットを用いてトラッキングのためのマークあるいは案内溝を形成する」技術が開示されている。またまた「図７（ｂ）は半径方向にそろったサーボ領域５００が割り当てられている場合で、トラッキングはサンプルサーボを用いることができる。アドレス情報はグレーコードかあるいは、ＣＡＰＡ（Ｃｏｍｐｌｉｍｅｎｔａｒｙ　Ａｌｌｏｃａｔｅｄ　Ｐｉｔ　Ａｄｄｒｅｓｓ）の形で読み取る。したがって、第１の光スポット１２１はトラックの間に配置されるスポット間隔は半整数倍となる。」との記載がある。 In Patent Document 2, “for tracking using a second spot while irradiating at least a first light spot and a second light spot on a disk-shaped optical recording medium and performing tracking using the first light spot. The technology for forming a mark or a guide groove is disclosed. In addition, “FIG. 7B shows a case where servo areas 500 aligned in the radial direction are allocated, and a sample servo can be used for tracking. The address information is gray code or CAPA (Complementary Allocated Pit Address). Accordingly, there is a description that the spot interval between the tracks of the first light spot 121 is a half-integer multiple.
　さらに特許文献３の要約には、「光ディスクの記録層内に複数のマーク層を形成する場合における半径方向の位置精度を高め得るようにする」ことを課題としている。そして、その解決手段として、「光ディスク装置１０は、光ピックアップ１７の光路形成部７０においてサーボ光ビームＬＳ、情報光ビームＬＭ及びトラッキング光ビームＬＫの光路をそれぞれ適切に調整した上で、対物レンズ１８によりサーボ光ビームＬＳ、情報光ビームＬＭ及びトラッキング光ビームＬＫをそれぞれ集光する。さらに光ピックアップ１７は、サーボ光ビームＬＳを基準層１０４に合焦させるよう対物レンズ１８のフォーカス制御を行うと共に、トラッキング光ビームＬＫを目標マーク層ＹＧの参照トラックＴＥに合焦させるよう当該対物レンズ１８のトラッキング制御を行うことにより、当該対物レンズ１８により集光する情報光ビームＬＭの焦点ＦＭを目標マーク層ＹＧの目標トラックＴＧに合わせることができる」と記載されている。 Further, the summary of Patent Document 3 has a problem that “the position accuracy in the radial direction can be improved when a plurality of mark layers are formed in the recording layer of the optical disk”. Then, as a means for solving the problem, “the optical disk apparatus 10 appropriately adjusts the optical paths of the servo light beam LS, the information light beam LM, and the tracking light beam LK in the optical path forming unit 70 of the optical pickup 17, and then the objective lens 18. Then, the servo light beam LS, the information light beam LM, and the tracking light beam LK are condensed respectively, and the optical pickup 17 controls the focus of the objective lens 18 so that the servo light beam LS is focused on the reference layer 104, and By performing tracking control of the objective lens 18 so that the tracking light beam LK is focused on the reference track TE of the target mark layer YG, the focus FM of the information light beam LM condensed by the objective lens 18 is changed to the target mark layer YG. Can be matched to the target track TG " It has been described.
特開２０１０－４００９３号公報JP 2010-40093 A 特開２００５－３０２０８５号公報JP 2005-302085 A 特開２００９－１５１９００号公報JP 2009-151900 A
　グルーブレスディスクでは、光ディスクとピックアップの半径方向の相対角度がずれる事により、記録層に照射される光スポットの相対位置がずれてしまう。この相対位置ずれにより、例えば追加記録時に既に記録してあるマークの上書きが発生し、データの消失を起こすという課題がある。 In the grooveless disc, the relative position of the light spot irradiated on the recording layer is shifted due to the deviation of the relative angle between the optical disc and the pickup in the radial direction. Due to this relative positional deviation, for example, there is a problem that overwriting of a mark already recorded at the time of additional recording occurs and data is lost.
　さらに光ディスク記録再生装置では記録に最適な光強度を求めるＯＰＣ（Ｏｐｔｉｍｕｍ Ｐｏｗｅｒ Ｃｏｎｔｒｏｌ）と呼ばれる処理を行う事でディスク毎の記録膜特性等のばらつきに対応している。ＯＰＣ処理ではディスク上に設けられたＯＰＣ用の領域にレーザ光の強度を変えながら記録を行うようにしており、最適な光強度からずれて記録される部分が生じる。 Further, the optical disk recording / reproducing apparatus copes with variations in recording film characteristics and the like for each disk by performing a process called OPC (Optimum Power Power Control) for obtaining the optimum light intensity for recording. In the OPC processing, recording is performed while changing the intensity of the laser beam in an OPC area provided on the disk, and a portion is recorded that deviates from the optimum light intensity.
　このため、上記の特許文献３の光ディスク記録再生装置でＯＰＣ領域にトラッキング制御を行う場合に最適な光強度からずれて記録された部分ではトラッキング誤差信号が正常に生成されず、トラッキングサーボ制御が不安定になるという課題が有る。このように、ＯＰＣ領域においても安定したトラッキングサーボ制御を行う事が必要である。 For this reason, when the optical disc recording / reproducing apparatus of Patent Document 3 performs tracking control in the OPC area, a tracking error signal is not normally generated in a portion recorded with a deviation from the optimum light intensity, and tracking servo control is not performed. There is a problem of becoming stable. Thus, it is necessary to perform stable tracking servo control even in the OPC region.
　また上記特許文献１に記載の方法では、記録済みの領域の最終記録位置から間を空けて追加記録が開始されるので、光ディスクの経時変化による反りや記録装置の違い等により各レーザビームの光軸に対して光ディスクにチルト（傾き）が存在していても記録済みの領域に上書きすることが抑制される。しかし、上記特許文献１の解決策では、追加記録する毎に無駄な領域が形成され、ディスク容量の低下を招くという課題がある。 Further, in the method described in Patent Document 1, additional recording is started with a gap from the final recording position of the recorded area. Therefore, the light of each laser beam is caused by warpage due to aging of the optical disk, differences in recording devices, and the like. Even if there is a tilt (tilt) in the optical disc with respect to the axis, overwriting in the recorded area is suppressed. However, the solution of the above-mentioned Patent Document 1 has a problem that a wasteful area is formed every time additional recording is performed, resulting in a decrease in disk capacity.
　そこで本発明は、グルーブレスディスクに対して適切に追加記録を行うことができる光ディスク装置を提供することを目的とする。 Therefore, an object of the present invention is to provide an optical disc apparatus capable of appropriately performing additional recording on a grooveless disc.
　上記課題は特許請求の範囲に記載の発明により解決される。 The above problem is solved by the invention described in the claims.
　本発明によれば、グルーブレスディスクに対して適切に追加記録を行うことができる光ディスク装置を提供することができる。 According to the present invention, it is possible to provide an optical disc apparatus capable of appropriately performing additional recording on a grooveless disc.
実施例１の光ディスク装置を示すブロック構成図である。1 is a block configuration diagram showing an optical disc apparatus of Embodiment 1. FIG. 実施例１のサーボエラー信号生成回路１０４を示すブロック構成図である。FIG. 2 is a block configuration diagram illustrating a servo error signal generation circuit 104 according to the first embodiment. 実施例１の信号処理回路１０５を示すブロック構成図である。1 is a block configuration diagram illustrating a signal processing circuit 105 according to a first embodiment. 光ディスク１０２の構造と、各レーザスポットを説明する図である。It is a figure explaining the structure of the optical disk 102, and each laser spot. 実施例１の記録層サブスポットＲ＿ＳｕｂＬＳの働きを説明する図である。FIG. 6 is a diagram illustrating the function of a recording layer sub-spot R_SubLS of Example 1. 実施例１のセットアップ処理のフローチャートである。3 is a flowchart of a setup process according to the first embodiment. 実施例１の記録処理のフローチャートである。3 is a flowchart of a recording process according to the first embodiment. 各種動作状態におけるトラッキング制御系及びフォーカス制御系の動作状態と、本明細書において定義した名称を示す対応表である。7 is a correspondence table showing the operating states of the tracking control system and the focus control system in various operating states and names defined in the present specification. 各種動作状態における制御信号の値を示す表である。It is a table | surface which shows the value of the control signal in various operation states. 各種動作状態において対物レンズ及びリレーレンズのフォーカス駆動及びトラッキング駆動がどの駆動信号を用いて行われるかを示す表である。It is a table | surface which shows which drive signal performs focus drive and tracking drive of an objective lens and a relay lens in various operation states. 記録層ＳｕｂＳｐｏｔトラッキング制御を行わずに記録層に対して情報の記録を行う場合の光ディスクとレーザスポットの位置関係を示す図である。It is a figure which shows the positional relationship of the optical disk and laser spot in the case of recording information with respect to a recording layer, without performing recording layer SubSpot tracking control. 記録層ＳｕｂＳｐｏｔトラッキング制御を行う場合の記録層上のレーザスポットを示す模式図である。It is a schematic diagram which shows the laser spot on a recording layer in the case of performing recording layer SubSpot tracking control. 実施例１による記録層ＳｕｂＳｐｏｔトラッキング制御を行う場合の記録層上のレーザスポットを示す模式図である。FIG. 6 is a schematic diagram showing a laser spot on a recording layer when performing recording layer SubSpot tracking control according to Example 1; 記録層トラックピッチ調整電圧生成回路が出力する電圧Ｖ＿ＴｐＡｄｊを変更した際の記録層上のレーザスポットを示す模式図である。It is a schematic diagram showing a laser spot on the recording layer when the voltage V_TpAdj output from the recording layer track pitch adjustment voltage generation circuit is changed. 記録層トラックピッチ調整電圧生成回路が出力する電圧Ｖ＿ＴｐＡｄｊを変更した際のＲ＿ＭａｉｎＴＥ信号を説明する波形図である。It is a wave form diagram explaining R_MainTE signal at the time of changing voltage V_TpAdj which a recording layer track pitch adjustment voltage generation circuit outputs. 本実施例のトラックピッチ調整を行っている最中の各部の信号と、電圧Ｖ＿ＴｐＡｄｊの最適値を算出する方法を説明する図である。It is a figure explaining the method of calculating the optimal value of the signal of each part in the middle of track pitch adjustment of a present Example, and voltage V_TpAdj. 実施例２の記録処理のフローチャートである。10 is a flowchart of recording processing according to the second embodiment. 実施例３の光スポットのトラッキング誤差信号生成マーク列切り替えの動作Switching operation of tracking error signal generation mark row of light spot in embodiment 3 実施例３の光ディスク記録再生装置の構成の模式図Schematic diagram of the configuration of the optical disc recording / reproducing apparatus of Example 3 実施例３が対象とする光ディスクの構造(断面)Structure (cross section) of the optical disk targeted by Example 3 実施例３の光ディスク記録再生装置に光ディスクを挿入時の光ディスク記録再生装置の処理フローProcessing flow of optical disc recording / reproducing apparatus when optical disc is inserted into optical disc recording / reproducing apparatus of embodiment 3 実施例３が対象とする光ディスクの構造(拡大図)Structure of optical disc targeted by Example 3 (enlarged view) 実施例３のOPC動作のフローチャートの例１Example 1 of flowchart of OPC operation of embodiment 3 実施例３のマーク記録パターンの例Example of mark recording pattern of Example 3 実施例３のOPC動作のフローチャートの例２Example 2 of flowchart of OPC operation of embodiment 3 実施例４のOPC動作のフローチャートの例Example of flowchart of OPC operation of embodiment 4 実施例４の上書きを行うレーザの強度の例Example of laser intensity for overwriting in Example 4 実施例３のトラッキング誤差信号生成手段の内部構成図Internal configuration diagram of tracking error signal generating means of embodiment 3 実施例３の記録コマンド受信時の動作フローOperation flow when receiving a recording command according to the third embodiment 実施例５の光ディスク装置を示す構成図FIG. 6 is a configuration diagram showing an optical disk device according to a fifth embodiment. 光ディスクの構造を示す模式図Schematic diagram showing the structure of an optical disc 記録時の記録層とサーボ層に合焦している光スポットの関係を示す模式図Schematic diagram showing the relationship between the light spot focused on the recording layer and servo layer during recording 実施例５におけるサーボ信号生成回路の構成図Configuration diagram of servo signal generation circuit in embodiment 5 オフセット場生じた場合の実施例５及び６の光ディスク装置におけるエラー信号の波形イメージ図Waveform image diagram of error signal in optical disc apparatus of Examples 5 and 6 when offset field occurs 実施例５及び６の光ディスク装置におけるエラー信号の波形イメージ図Waveform image diagram of error signal in optical disc apparatus of Examples 5 and 6 実施例５における光ディスク装置の動作概要を示すフローチャートFlowchart showing an outline of the operation of the optical disk apparatus in the fifth embodiment. 実施例５における光ディスク装置の記録動作概要を示すフローチャートFlowchart showing an outline of recording operation of the optical disc apparatus in Embodiment 5 実施例６の光ディスク装置を示す構成図FIG. 6 is a configuration diagram illustrating an optical disc device according to a sixth embodiment 実施例６の角度可変立ち上げミラーの角度変化による光軸の変化のイメージ図Image of change of optical axis due to change of angle of variable angle raising mirror of embodiment 6 角度可変立ち上げミラーが反時計周りに回転した場合のイメージ図Image diagram when the variable angle raising mirror rotates counterclockwise 実施例５及び６の光ディスク装置におけるエラー信号の波形イメージ図Waveform image diagram of error signal in optical disc apparatus of Examples 5 and 6
　以下、本発明の実施の形態を図面に基づいて説明する。 Hereinafter, embodiments of the present invention will be described with reference to the drawings.
　図１は、本発明に従う光ディスク装置の一実施例を示すブロック構成図である。
光ディスク装置１０１は装置に装着された光ディスク１０２にレーザ光を照射することで情報の記録または再生を行い、ＳＡＴＡ（Ｓｅｒｉａｌ　Ａｄｖａｎｃｅｄ　Ｔｅｃｈｎｏｌｏｇｙ　Ａｔｔａｃｈｍｅｎｔ）などのインターフェースを通じてＰＣ（Ｐｅｒｓｏｎａｌ　Ｃｏｍｐｕｔｅｒ）などのホスト１１４と通信を行う。 FIG. 1 is a block diagram showing an embodiment of an optical disc apparatus according to the present invention.
The optical disc apparatus 101 records or reproduces information by irradiating an optical disc 102 mounted on the apparatus with laser light, and communicates with a host 114 such as a PC (Personal Computer) through an interface such as SATA (Serial Advanced Technology Attachment). Do.
　光ディスク１０２の構造を図４に例示する。光ディスク１０２はトラック（ガイド溝）の構造を持つサーボ層と、トラックの構造を持たないＮ個の記録層（Ｎ≧１、Ｎは自然数）を有する。本明細書では、サーボ層上のトラックをサーボ層トラックと称する。またサーボ層トラックのピッチ（間隔）を、Ｔｐで表す。以下の説明では、記録膜を塗布された記録面が膜厚方向に積層されて複数の記録層を形成しているものとする。図４において、Ｓ＿ＬＢはサーボ層に照射されるレーザ光、Ｒ＿ＬＢは記録層に照射されるレーザ光を示している。 The structure of the optical disk 102 is illustrated in FIG. The optical disk 102 has a servo layer having a track (guide groove) structure and N recording layers (N ≧ 1, N is a natural number) not having a track structure. In this specification, a track on the servo layer is referred to as a servo layer track. The pitch (interval) of the servo layer tracks is represented by Tp. In the following description, it is assumed that the recording surface coated with the recording film is laminated in the film thickness direction to form a plurality of recording layers. In FIG. 4, S_LB indicates the laser beam irradiated on the servo layer, and R_LB indicates the laser beam irradiated on the recording layer.
　本実施例の光ディスク装置１０１は対物レンズ１３１１によって、記録層上に記録層メインスポットＲ＿ＭａｉｎＬＳと、記録層サブスポットＲ＿ＳｕｂＬＳの、２つのレーザスポットを生じる。またサーボ層に対してサーボ層レーザスポットＳ＿ＬＳを生じることができる。ここで、記録層上に生じる２つのレーザスポットＲ＿ＭａｉｎＬＳ、Ｒ＿ＳｕｂＬＳの半径方向の距離は、サーボ層のトラックピッチＴｐに略等しくなるように配置する。 In the optical disk apparatus 101 of the present embodiment, the objective lens 1311 generates two laser spots on the recording layer, that is, a recording layer main spot R_MainLS and a recording layer sub-spot R_SubLS. Also, a servo layer laser spot S_LS can be generated for the servo layer. Here, the radial distance between the two laser spots R_MainLS and R_SubLS generated on the recording layer is arranged so as to be substantially equal to the track pitch Tp of the servo layer.
　次に、本実施例の記録層サブスポットＲ＿ＳｕｂＬＳの働きについて図５を用いて説明する。図５は光ディスク１０２に対して情報を追加記録している際の光ディスク１０２と、各レーザスポットの位置関係を示している。 Next, the function of the recording layer sub-spot R_SubLS of this embodiment will be described with reference to FIG. FIG. 5 shows the positional relationship between the optical disc 102 and each laser spot when information is additionally recorded on the optical disc 102.
　図５においては、内周から外周に向かって情報を記録していく場合を示している。即ち、記録層メインスポットＲ＿ＭａｉｎＬＳよりも内周方向（図５において左方向）は、記録済みのマーク列が存在することになる。記録層上に形成されたマーク列を、本明細書では以下、記録層トラックと称する。 FIG. 5 shows a case where information is recorded from the inner periphery toward the outer periphery. That is, a recorded mark row exists in the inner circumferential direction (left direction in FIG. 5) from the recording layer main spot R_MainLS. The mark row formed on the recording layer is hereinafter referred to as a recording layer track in this specification.
　記録中は、記録層サブスポットＲ＿ＳｕｂＬＳを用いてトラッキング制御をかけながら、記録層メインスポットＲ＿ＭａｉｎＬＳにて情報の記録を行う。Ｒ＿ＭａｉｎＬＳ、Ｒ＿ＳｕｂＬＳの半径方向の距離は、サーボ層のトラックピッチＴｐに略等しいため、図５に示すように記録層メインスポットＲ＿ＭａｉｎＬＳで内周から外周に向かって情報を記録している際、記録中のトラックに隣接する記録層トラック上に記録層サブスポットＲ＿ＳｕｂＬＳを照射することで、Ｔｐだけ外周側の位置に記録層メインスポットＲ＿ＭａｉｎＬＳの位置が制御され、情報が記録される。このとき、記録層サブスポットＲ＿ＳｕｂＬＳが照射される記録層トラックのことを、以下、隣接記録層トラックと称する。また本明細書においては、図５に示したように、ディスク面に垂直な方向をフォーカス方向、ディスク半径方向を半径方向、ディスク面に平行な面内において半径方向に垂直な方向を接線方向と、それぞれ称することにする。 During recording, information is recorded at the recording layer main spot R_MainLS while tracking control is performed using the recording layer sub-spot R_SubLS. Since the distance in the radial direction of R_MainLS and R_SubLS is substantially equal to the track pitch Tp of the servo layer, when information is recorded from the inner circumference to the outer circumference at the recording layer main spot R_MainLS as shown in FIG. By irradiating the recording layer sub-spot R_SubLS on the recording layer track adjacent to this track, the position of the recording layer main spot R_MainLS is controlled at a position on the outer peripheral side by Tp, and information is recorded. At this time, the recording layer track irradiated with the recording layer sub-spot R_SubLS is hereinafter referred to as an adjacent recording layer track. In this specification, as shown in FIG. 5, the direction perpendicular to the disk surface is the focus direction, the disk radial direction is the radial direction, and the direction perpendicular to the radial direction in the plane parallel to the disk surface is the tangential direction. , Respectively.
　本光ディスク装置１０１は、光ピックアップ１０３と、サーボ制御に用いる各種エラー信号を生成するサーボエラー信号生成回路１０４と、信号処理回路１０５と、信号処理回路１０６と、光ディスク１０２を回転するためのスピンドルモータ１０７と、スピンドル駆動回路１０８が生成する回転信号に応じてスピンドルモータ１０７を駆動すると共にスピンドルモータ１０７の回転速度に対応した周波数のＦＧ信号を生成するスピンドル駆動回路１０８と、光ピックアップ１０３中に備えられたアクチュエータ１３１２をフォーカス方向及び半径方向に駆動するアクチュエータ駆動回路１０９と、サーボ層レーザスポットＳ＿ＬＳがフォーカス方向及び半径方向に移動するように、光ピックアップ１０３中に備えられたリレーレンズ１３２１を駆動するリレーレンズ駆動回路１１０と、光ピックアップ１０３中に備えられた球面収差補正素子１３０９を駆動するための収差補正素子駆動回路１１１と、光ピックアップ１０３を光ディスク１０２の半径方向に移動するスライダモータ１１２と、スライダモータ１１２を駆動するスライダ駆動回路１１３を備えている。 The optical disk apparatus 101 includes an optical pickup 103, a servo error signal generation circuit 104 that generates various error signals used for servo control, a signal processing circuit 105, a signal processing circuit 106, and a spindle motor for rotating the optical disk 102. 107, a spindle drive circuit 108 that drives the spindle motor 107 according to the rotation signal generated by the spindle drive circuit 108 and generates an FG signal having a frequency corresponding to the rotation speed of the spindle motor 107, and an optical pickup 103. Actuator driving circuit 109 for driving the actuator 1312 in the focus direction and the radial direction, and the relay lens 13 provided in the optical pickup 103 so that the servo layer laser spot S_LS moves in the focus direction and the radial direction. 1, a relay lens driving circuit 110 for driving 1, an aberration correction element driving circuit 111 for driving a spherical aberration correction element 1309 provided in the optical pickup 103, and a slider for moving the optical pickup 103 in the radial direction of the optical disk 102. A motor 112 and a slider drive circuit 113 for driving the slider motor 112 are provided.
　次に、本実施例におけるサーボエラー信号生成回路１０４の構成について、図２を用いて説明する。サーボエラー信号生成回路１０４は、記録層トラックと記録層サブスポットＲ＿ＳｕｂＬＳの位置のずれ量を示す記録層Ｓｕｂトラッキングエラー信号Ｒ＿ＳｕｂＴＥを生成する記録層Ｓｕｂトラッキングエラー信号生成回路１４０１と、記録層トラックと記録層メインスポットＲ＿ＭａｉｎＬＳの位置のずれ量を示す記録層Ｍａｉｎトラッキングエラー信号Ｒ＿ＭａｉｎＴＥを生成する記録層Ｍａｉｎトラッキングエラー信号生成回路１４０２と、光ディスク１０２のサーボ層トラックとサーボ層レーザスポットＳ＿ＬＳとの位置ずれ量を示すサーボ層トラッキングエラー信号Ｓ＿ＴＥを生成するサーボ層トラッキングエラー信号生成回路１４０３と、光ディスク１０２の記録層とレーザスポットＲ＿ＭａｉｎＬＳの焦点位置とのずれ量を示す記録層フォーカスエラー信号Ｒ＿ＦＥを生成する記録層フォーカスエラー信号生成回路１４０４と、光ディスク１０２のサーボ層とレーザスポットＳ＿ＬＳの焦点位置とのずれ量を示すサーボ層フォーカスエラー信号Ｓ＿ＦＥを生成するサーボ層フォーカスエラー信号生成回路１４０５を備えている。各エラー信号は、電位Ｖｒｅｆを基準として出力される。 Next, the configuration of the servo error signal generation circuit 104 in this embodiment will be described with reference to FIG. The servo error signal generation circuit 104 includes a recording layer sub tracking error signal generation circuit 1401 that generates a recording layer sub tracking error signal R_SubTE indicating the amount of displacement between the recording layer track and the recording layer sub-spot R_SubLS. A recording layer Main tracking error signal generation circuit 1402 for generating a recording layer Main tracking error signal R_MainTE indicating the amount of positional deviation of the layer main spot R_MainLS, and a positional deviation amount between the servo layer track of the optical disc 102 and the servo layer laser spot S_LS. A servo layer tracking error signal generation circuit 1403 that generates a servo layer tracking error signal S_TE, and a deviation amount between the recording layer of the optical disc 102 and the focal position of the laser spot R_MainLS. A recording layer focus error signal generation circuit 1404 for generating a recording layer focus error signal R_FE, and a servo layer focus for generating a servo layer focus error signal S_FE indicating a deviation amount between the servo layer of the optical disk 102 and the focal position of the laser spot S_LS. An error signal generation circuit 1405 is provided. Each error signal is output with reference to the potential Vref.
　次に、本実施例における信号処理回路１０５の構成について、図３を用いて説明する。信号処理回路１０５は光ディスク装置の各種の信号処理を行う回路であり、電位Ｖｒｅｆを基準として動作する。信号処理回路１０５は、システム制御回路１５０１と、
Ｒ＿ＦＥ信号に応じて対物レンズ１３１１をフォーカス方向に駆動するための信号を生成する記録層フォーカス制御回路１５０２と、Ｒ＿ＦＯＮ信号に基づいて記録層フォーカス制御回路１５０２の出力を切り替えるスイッチ１５０３と、対物レンズ１３１１をフォーカス方向に駆動するための電圧を生成する記録層フォーカス駆動電圧生成回路１５０４と、スイッチ１５０３の出力信号と記録層フォーカス駆動電圧生成回路１５０４の出力信号を加算してＲ＿ＦＯＤ信号として出力する加算器１５０５と、
Ｓ＿ＦＥ信号に応じてリレーレンズ１３２１をフォーカス方向に駆動するための信号を生成するサーボ層フォーカス制御回路１５０６と、Ｓ＿ＦＯＮ信号に基づいてサーボ層フォーカス制御回路１５０６の出力を切り替えるスイッチ１５０７と、リレーレンズ１３２１をフォーカス方向に駆動するための電圧を生成するサーボ層フォーカス駆動電圧生成回路１５０８と、スイッチ１５０７の出力信号とサーボ層フォーカス駆動電圧生成回路１５０８の出力信号を加算してＳ＿ＦＯＤ信号として出力する加算器１５０９と、
Ｓ＿ＴＥ信号に応じてリレーレンズ１３２１もしくは対物レンズ１３１１を半径方向に駆動するための信号を生成するサーボ層トラッキング制御回路１５１０と、Ｓ＿ＴＯＮ信号に基づいてサーボ層トラッキング制御回路１５１０の出力を切り替えてＳ＿ＴＲＤ信号として出力するスイッチ１５１１と、ＲＬ＿ＴＳＥＬ信号に基づいてＳ＿ＴＲＤ信号の出力を切り替えるセレクタ１５１２と、
Ｒ＿ＴＥＳＥＬ信号に基づきＲ＿Ｓｕｂ信号またはＲ＿Ｍａｉｎ信号のいずれかを選択してＲ＿ＴＥ信号として出力するセレクタ１５１３と、Ｒ＿ＴｐＡｄｊ信号を出力する記録層トラックピッチ調整電圧生成回路１５１４と、セレクタ１５１３の出力信号と記録層トラックピッチ調整電圧生成回路１５１４の出力信号を加算して出力する加算器１５１５と、加算器１５１５の出力信号に応じて対物レンズ１３１１を半径方向に駆動するための信号を生成する記録層トラッキング制御回路１５１６と、Ｒ＿ＴＯＮ信号に基づいて記録層トラッキング制御回路１５１６の出力を切り替えてＲ＿ＴＲＤ信号として出力するスイッチ１５１７と、ＯＬ＿ＴＳＥＬ信号に基づきＲ＿ＴＲＤ信号またはＳ＿ＴＲＤ信号のいずれかを選択して出力するセレクタ１５１８と、対物レンズ１３１１を半径方向に駆動するための電圧を生成するトラッキング駆動電圧生成回路１５１９と、セレクタ１５１８の出力信号とトラッキング駆動電圧生成回路１５１９の出力信号を加算してＯＬ＿ＴＲＤ信号として信号として出力する加算器１５２０と、
Ｒ＿Ｍａｉｎ信号をモニタする記録層ＭａｉｎＴＥ信号モニタ回路１５２３と、スライダモータ１１２を移動させるための信号を生成するスライダ制御回路１５２１と、スピンドルモータ１０７を回転させるための回転信号を生成するスピンドル制御回路１５２２を備えている。 Next, the configuration of the signal processing circuit 105 in this embodiment will be described with reference to FIG. The signal processing circuit 105 is a circuit that performs various types of signal processing of the optical disc apparatus, and operates with the potential Vref as a reference. The signal processing circuit 105 includes a system control circuit 1501,
A recording layer focus control circuit 1502 that generates a signal for driving the objective lens 1311 in the focus direction according to the R_FE signal, a switch 1503 that switches the output of the recording layer focus control circuit 1502 based on the R_FON signal, and the objective lens 1311 Recording layer focus driving voltage generation circuit 1504 for generating a voltage for driving the image in the focusing direction, and an adder for adding the output signal of the switch 1503 and the output signal of the recording layer focus driving voltage generation circuit 1504 to output as an R_FOD signal 1505,
A servo layer focus control circuit 1506 that generates a signal for driving the relay lens 1321 in the focus direction according to the S_FE signal, a switch 1507 that switches the output of the servo layer focus control circuit 1506 based on the S_FON signal, and the relay lens 1321 Servo layer focus drive voltage generation circuit 1508 for generating a voltage for driving the image in the focus direction, and an adder for adding the output signal of the switch 1507 and the output signal of the servo layer focus drive voltage generation circuit 1508 to output as an S_FOD signal 1509,
A servo layer tracking control circuit 1510 that generates a signal for driving the relay lens 1321 or the objective lens 1311 in the radial direction according to the S_TE signal, and an output of the servo layer tracking control circuit 1510 based on the S_TON signal to switch the S_TRD signal A switch 1511 that outputs as a signal, a selector 1512 that switches the output of the S_TRD signal based on the RL_TSEL signal,
A selector 1513 that selects either the R_Sub signal or the R_Main signal based on the R_TESEL signal and outputs it as the R_TE signal, a recording layer track pitch adjustment voltage generation circuit 1514 that outputs the R_TpAdj signal, and the output signal and recording layer track of the selector 1513 An adder 1515 that adds and outputs the output signal of the pitch adjustment voltage generation circuit 1514, and a recording layer tracking control circuit 1516 that generates a signal for driving the objective lens 1311 in the radial direction according to the output signal of the adder 1515. A switch 1517 that switches the output of the recording layer tracking control circuit 1516 based on the R_TON signal and outputs it as an R_TRD signal, and a selector that selects and outputs either the R_TRD signal or the S_TRD signal based on the OL_TSEL signal. 1515, a tracking drive voltage generation circuit 1519 that generates a voltage for driving the objective lens 1311 in the radial direction, and the output signal of the selector 1518 and the output signal of the tracking drive voltage generation circuit 1519 are added to form an OL_TRD signal. An adder 1520 that outputs as
A recording layer MainTE signal monitor circuit 1523 that monitors the R_Main signal, a slider control circuit 1521 that generates a signal for moving the slider motor 112, and a spindle control circuit 1522 that generates a rotation signal for rotating the spindle motor 107. I have.
　光ピックアップ１０３はサーボ層にサーボ制御を行うとともに、ディスク上の位置に対応したアドレス及びディスク固有の情報を再生するためのサーボ層光学系と、サーボ層からの距離が異なる複数の記録層にデータを記録・再生するための記録層光学系で構成されている。 The optical pickup 103 performs servo control on the servo layer, and also stores data in a servo layer optical system for reproducing an address corresponding to a position on the disk and information unique to the disk, and a plurality of recording layers at different distances from the servo layer. Is composed of a recording layer optical system for recording / reproducing data.
　まず、記録層光学系の動作について説明する。レーザパワー制御回路１３０１は、システム制御回路１５０１によって制御されており、レーザダイオード１３０２を駆動する電流を出力する。この駆動電流は、レーザノイズを抑制するために数百ＭＨｚの高周波重畳が印加されている。レーザダイオード１３０２は、駆動電流に応じた波形で例えば波長４０５ｎｍのレーザ光Ｒ＿ＬＢを出射する。出射されたレーザ光はコリメータレンズ１３０３にて平行光となり、ビームスプリッタ１３０４で一部が反射し、集光レンズ１３０５によってパワーモニタ１３０６に集光する。パワーモニタ１３０６は、レーザ光の強度に応じた電流または電圧をＲ＿ＰＭ信号としてシステム制御回路１５０１にフィードバックする。これによって光ディスク１０２の記録層に集光するレーザ光Ｒ＿ＬＢの強度が、たとえば２ｍＷなど所望の値に保持される。一方、ビームスプリッタ１３０４を透過したレーザ光Ｒ＿ＬＢは偏光ビームスプリッタ１３０７にて反射し、収差補正素子駆動回路１１１にて駆動される球面収差補正素子１３０９によって収束・発散が制御され、ダイクロイックミラー１３０８を透過する。ダイクロイックミラー１３０８は特定の波長の光を反射し、その他の波長の光を透過する光学素子である。ここでは波長４０５ｎｍの光を透過し、６５０ｎｍの光を反射するものとする。ダイクロイックミラー１３０８を透過したレーザ光Ｒ＿ＬＢは、１／４波長板１３１０にて円偏光となり、対物レンズ１３１１によって光ディスク１０２の記録層にレーザスポットＲ＿ＭａｉｎＬＳとして集光する。更に図４で説明したように、記録層メインスポットＲ＿ＭａｉｎＬＳから半径方向にサーボ層のトラックピッチＴｐだけ離れた位置に、記録層サブスポットＲ＿ＳｕｂＬＳとしても集光する。 First, the operation of the recording layer optical system will be described. The laser power control circuit 1301 is controlled by the system control circuit 1501 and outputs a current for driving the laser diode 1302. This driving current is applied with high frequency superposition of several hundred MHz in order to suppress laser noise. The laser diode 1302 emits a laser beam R_LB having a wavelength of 405 nm, for example, with a waveform corresponding to the drive current. The emitted laser light is converted into parallel light by the collimator lens 1303, partly reflected by the beam splitter 1304, and condensed on the power monitor 1306 by the condenser lens 1305. The power monitor 1306 feeds back a current or voltage corresponding to the intensity of the laser light to the system control circuit 1501 as an R_PM signal. As a result, the intensity of the laser beam R_LB focused on the recording layer of the optical disc 102 is maintained at a desired value such as 2 mW. On the other hand, the laser beam R_LB that has passed through the beam splitter 1304 is reflected by the polarization beam splitter 1307, and the convergence and divergence are controlled by the spherical aberration correction element 1309 driven by the aberration correction element drive circuit 111, and transmitted through the dichroic mirror 1308. To do. The dichroic mirror 1308 is an optical element that reflects light of a specific wavelength and transmits light of other wavelengths. Here, it is assumed that light having a wavelength of 405 nm is transmitted and light having a wavelength of 650 nm is reflected. The laser beam R_LB that has passed through the dichroic mirror 1308 becomes circularly polarized light by the quarter-wave plate 1310 and is condensed as a laser spot R_MainLS on the recording layer of the optical disc 102 by the objective lens 1311. Further, as described with reference to FIG. 4, the recording layer sub-spot R_SubLS is condensed at a position separated from the recording layer main spot R_MainLS by the track pitch Tp of the servo layer in the radial direction.
　ここで、球面収差補正素子１３０９はシステム制御回路１５０１から収差補正素子駆動回路１１１を介してグルーブレスディスクの記録層に応じた所定の位置となるように制御が行われる。光ディスク１０２によって反射したレーザ光Ｒ＿ＬＢは、光ディスク１０２に記録された情報に応じて強度が変調される。１／４波長板１３１０にて直線偏光となり、ダイクロイックミラー１３０８を経て、偏光ビームスプリッタ１３０７および球面収差補正素子１３０９を透過する。透過したレーザ光Ｒ＿ＬＢは、集光レンズ１３１３によってディテクタ１３１４及びディテクタ１３２４に集光する。 Here, the spherical aberration correction element 1309 is controlled from the system control circuit 1501 via the aberration correction element driving circuit 111 so as to be at a predetermined position corresponding to the recording layer of the grooveless disk. The intensity of the laser beam R_LB reflected by the optical disc 102 is modulated according to information recorded on the optical disc 102. The light is linearly polarized by the quarter-wave plate 1310, passes through the dichroic mirror 1308, and passes through the polarization beam splitter 1307 and the spherical aberration correction element 1309. The transmitted laser beam R_LB is condensed on the detector 1314 and the detector 1324 by the condenser lens 1313.
　ディテクタ１３１４及びディテクタ１３２４はレーザ光Ｒ＿ＬＢの強度を検出し、これに応じた信号を出力する。このとき、ディテクタ１３１４は、記録層メインスポットＲ＿ＭａｉｎＬＳにおいて反射した光の強度を検出し、ディテクタ１３２４は、記録層サブスポットＲ＿ＳｕｂＬＳにおいて反射した光の強度を検出する。 The detector 1314 and the detector 1324 detect the intensity of the laser beam R_LB and output a signal corresponding to the detected intensity. At this time, the detector 1314 detects the intensity of the light reflected at the recording layer main spot R_MainLS, and the detector 1324 detects the intensity of the light reflected at the recording layer sub-spot R_SubLS.
　ディテクタ１３１４の出力信号はサーボエラー信号生成回路１０４及び再生信号生成回路１０６へ、またディテクタ１３２４の出力信号はサーボエラー信号生成回路１０４へ出力される。 The output signal of the detector 1314 is output to the servo error signal generation circuit 104 and the reproduction signal generation circuit 106, and the output signal of the detector 1324 is output to the servo error signal generation circuit 104.
　サーボエラー信号生成回路１０４において、記録層フォーカスエラー信号生成回路１４０４は、ディテクタ１３１４から出力された信号から、光ディスク１０２の記録層とレーザスポットＲ＿ＭａｉｎＬＳの焦点位置とのずれ量を示す記録層フォーカスエラー信号Ｒ＿ＦＥを生成する。またディテクタ１３１４から出力された信号は記録層Ｍａｉｎトラッキングエラー信号生成回路１４０２にも入力され、記録層トラックと記録層メインスポットＲ＿ＭａｉｎＬＳの位置のずれ量を示す記録層Ｍａｉｎトラッキングエラー信号Ｒ＿ＭａｉｎＴＥを生成する。更に、ディテクタ１３２４から出力された信号は記録層Ｓｕｂトラッキングエラー信号生成回路１４０１に入力され、記録層トラックと記録層サブスポットＲ＿ＳｕｂＬＳの位置のずれ量を示す記録層Ｓｕｂトラッキングエラー信号Ｒ＿ＳｕｂＴＥを生成する。 In the servo error signal generation circuit 104, a recording layer focus error signal generation circuit 1404 indicates a recording layer focus error signal indicating the amount of deviation between the recording layer of the optical disc 102 and the focal position of the laser spot R_MainLS from the signal output from the detector 1314. R_FE is generated. The signal output from the detector 1314 is also input to the recording layer main tracking error signal generation circuit 1402 to generate a recording layer main tracking error signal R_MainTE indicating the amount of displacement between the recording layer track and the recording layer main spot R_MainLS. Further, the signal output from the detector 1324 is input to the recording layer sub tracking error signal generation circuit 1401 to generate a recording layer sub tracking error signal R_SubTE indicating the amount of displacement between the recording layer track and the recording layer sub-spot R_SubLS.
　サーボエラー信号生成回路１０４で生成されたエラー信号は信号処理回路１０５に入力され、記録層に対するフォーカス制御、トラッキング制御が行われる。 The error signal generated by the servo error signal generation circuit 104 is input to the signal processing circuit 105, and focus control and tracking control for the recording layer are performed.
　記録層フォーカス制御回路１５０２は、システム制御回路１５０１からの指令信号により、記録層フォーカスエラー信号Ｒ＿ＦＥに対してゲインと位相の補償を行い、記録層に対するフォーカス制御を行うための駆動信号を出力する。記録層フォーカス制御回路１５０２から出力された駆動信号は、スイッチ１５０３、加算器１５０５を介してアクチュエータ駆動回路１０９に入力される。 The recording layer focus control circuit 1502 performs gain and phase compensation for the recording layer focus error signal R_FE in response to a command signal from the system control circuit 1501, and outputs a drive signal for performing focus control on the recording layer. The drive signal output from the recording layer focus control circuit 1502 is input to the actuator drive circuit 109 via the switch 1503 and the adder 1505.
　スイッチ１５０３はシステム制御回路１５０１の出力するＲ＿ＦＯＮ信号に基づき、記録層フォーカス制御回路１５０２の出力信号もしくは基準電位Ｖｒｅｆを選択して出力する。Ｒ＿ＦＯＮ信号としてＨｉｇｈレベルが入力されると、スイッチ１５０３は端子ａを選択して、記録層フォーカス制御回路１５０２の出力信号が加算器１５０５を介してアクチュエータ駆動回路１０９に出力される。一方でＲ＿ＦＯＮ信号としてＬｏｗレベルが入力されると、スイッチ１５０３は端子ｂを選択し、基準電位Ｖｒｅｆを出力する。 The switch 1503 selects and outputs the output signal of the recording layer focus control circuit 1502 or the reference potential Vref based on the R_FON signal output from the system control circuit 1501. When the High level is input as the R_FON signal, the switch 1503 selects the terminal a, and the output signal of the recording layer focus control circuit 1502 is output to the actuator drive circuit 109 via the adder 1505. On the other hand, when the Low level is input as the R_FON signal, the switch 1503 selects the terminal b and outputs the reference potential Vref.
　この結果、Ｒ＿ＦＯＮ信号は記録層に対するフォーカス制御のオン・オフを指示する信号となる。またスイッチ１５０３は、記録層に対するフォーカス制御のオン、オフを切り替えるスイッチとして機能する。Ｒ＿ＦＯＮ信号がＬｏｗからＨｉｇｈに切り替わることで記録層に対するフォーカス制御がオンされることになり、この動作はフォーカス引き込み動作と呼ばれる。 As a result, the R_FON signal is a signal for instructing on / off of focus control for the recording layer. The switch 1503 functions as a switch for switching on / off the focus control for the recording layer. When the R_FON signal is switched from Low to High, the focus control for the recording layer is turned on, and this operation is called a focus pull-in operation.
　記録層フォーカス駆動電圧生成回路１５０４は、システム制御回路１５０１からの指令信号により、所定の電圧を出力する。記録層フォーカス駆動電圧生成回路１５０４は例えば、フォーカススイープ動作におけるスイープ電圧や、フォーカスジャンプ時のジャンプ電圧を出力する。記録層フォーカス駆動電圧生成回路１５０４は例えば、一般的なＣＰＵを用いることができる。 The recording layer focus drive voltage generation circuit 1504 outputs a predetermined voltage in response to a command signal from the system control circuit 1501. The recording layer focus drive voltage generation circuit 1504 outputs, for example, a sweep voltage in the focus sweep operation and a jump voltage at the time of focus jump. As the recording layer focus drive voltage generation circuit 1504, for example, a general CPU can be used.
　加算器１５０５は、スイッチ１５０３の出力信号と記録層フォーカス駆動電圧生成回路１５０４の出力信号を加算し、記録層フォーカス駆動信号Ｒ＿ＦＯＤとしてアクチュエータ駆動回路１０９に出力する。 The adder 1505 adds the output signal of the switch 1503 and the output signal of the recording layer focus drive voltage generation circuit 1504, and outputs the result to the actuator drive circuit 109 as the recording layer focus drive signal R_FOD.
　アクチュエータ駆動回路１０９は、記録層フォーカス駆動信号Ｒ＿ＦＯＤに従って対物レンズ１３１１と一体で動作するように構成されたアクチュエータ１３１２をディスク面に垂直な方向に駆動する。アクチュエータ駆動回路１０９は記録層フォーカス駆動信号Ｒ＿ＦＯＤに応じてアクチュエータ１３１２を駆動することでフォーカス方向に対物レンズ１３１１の位置を変位させ、レーザ光Ｒ＿ＬＢが記録層に合焦するように記録層フォーカスサーボ制御を行う。本明細書では、この制御のことを記録層フォーカス制御と呼ぶ。 Actuator drive circuit 109 drives actuator 1312 configured to operate integrally with objective lens 1311 in a direction perpendicular to the disk surface in accordance with recording layer focus drive signal R_FOD. The actuator drive circuit 109 drives the actuator 1312 according to the recording layer focus drive signal R_FOD to displace the position of the objective lens 1311 in the focus direction, and the recording layer focus servo control so that the laser beam R_LB is focused on the recording layer. I do. In this specification, this control is called recording layer focus control.
　記録層トラッキング制御回路１５１６は、システム制御回路１５０１からの指令信号により、記録層トラッキングエラー信号Ｒ＿ＴＥに対してゲインと位相の補償を行い、記録層に対するトラッキング制御を行うための駆動信号を出力する。記録層トラッキング制御回路１５１６から出力された駆動信号は、スイッチ１５１７、セレクタ１５１８、加算器１５２０を介してアクチュエータ駆動回路１０９に入力される。 The recording layer tracking control circuit 1516 performs gain and phase compensation for the recording layer tracking error signal R_TE according to a command signal from the system control circuit 1501, and outputs a drive signal for performing tracking control on the recording layer. The drive signal output from the recording layer tracking control circuit 1516 is input to the actuator drive circuit 109 via the switch 1517, the selector 1518, and the adder 1520.
　ここで、記録層トラッキング制御回路１５１６に入力される記録層トラッキングエラー信号Ｒ＿ＴＥは、Ｒ＿Ｓｕｂ信号またはＲ＿Ｍａｉｎ信号のいずれかであり、システム制御回路１５０１からのＲ＿ＴＥＳＥＬ信号に基づき、セレクタ１５１３において信号選択が行われる。Ｒ＿ＴＥＳＥＬ信号としてＨｉｇｈレベルが入力されると、セレクタ１５１３は端子ｇを選択してＲ＿Ｓｕｂ信号を出力し、Ｒ＿ＴＥＳＥＬ信号としてＬｏｗレベルが入力されると、セレクタ１５１３は端子ｈを選択してＲ＿Ｍａｉｎ信号を出力する。 Here, the recording layer tracking error signal R_TE input to the recording layer tracking control circuit 1516 is either an R_Sub signal or an R_Main signal, and the selector 1513 performs signal selection based on the R_TESEL signal from the system control circuit 1501. Is called. When the High level is input as the R_TESEL signal, the selector 1513 selects the terminal g and outputs the R_Sub signal. When the Low level is input as the R_TESEL signal, the selector 1513 selects the terminal h and outputs the R_Main signal. To do.
　更に、セレクタ１５１３で選択された記録層トラッキングエラー信号Ｒ＿ＴＥは、加算器１５１５にて記録層トラックピッチ調整電圧生成回路１５１４の出力する信号Ｒ＿ＴｐＡｄｊと加算された後、記録層トラッキング制御回路１５１６に入力される。記録層トラックピッチ調整電圧生成回路１５１４は、Ｒ＿ＴｐＡｄｊ信号として所定の電圧を出力する。以下、Ｒ＿ＴｐＡｄｊ信号の電圧をＶ＿ＴｐＡｄｊで表す。 Further, the recording layer tracking error signal R_TE selected by the selector 1513 is added to the signal R_TpAdj output from the recording layer track pitch adjustment voltage generation circuit 1514 by the adder 1515 and then input to the recording layer tracking control circuit 1516. The The recording layer track pitch adjustment voltage generation circuit 1514 outputs a predetermined voltage as the R_TpAdj signal. Hereinafter, the voltage of the R_TpAdj signal is represented by V_TpAdj.
　スイッチ１５１７はシステム制御回路１５０１の出力するＲ＿ＴＯＮ信号に基づき、記録層トラッキング制御回路１５１６の出力信号もしくは基準電位Ｖｒｅｆを選択して、記録層トラッキング駆動信号Ｒ＿ＴＲＤとして出力する。Ｒ＿ＴＯＮ信号としてＨｉｇｈレベルが入力されると、スイッチ１５１７は端子ｉを選択して、記録層トラッキング制御回路１５１６の出力信号がアクチュエータ駆動回路１０９に出力される。一方でＲ＿ＴＯＮ信号としてＬｏｗレベルが入力されると、スイッチ１５１７は端子ｊを選択し、基準電位Ｖｒｅｆを出力する。 The switch 1517 selects the output signal of the recording layer tracking control circuit 1516 or the reference potential Vref based on the R_TON signal output from the system control circuit 1501, and outputs it as the recording layer tracking drive signal R_TRD. When the high level is input as the R_TON signal, the switch 1517 selects the terminal i, and the output signal of the recording layer tracking control circuit 1516 is output to the actuator drive circuit 109. On the other hand, when the Low level is input as the R_TON signal, the switch 1517 selects the terminal j and outputs the reference potential Vref.
　この結果、Ｒ＿ＴＯＮ信号は記録層に対するトラッキング制御のオン・オフを指示する信号となる。またスイッチ１５１７は、記録層に対するトラッキング制御のオン、オフを切り替えるスイッチとして機能する。Ｒ＿ＴＯＮ信号がＬｏｗからＨｉｇｈに切り替わることで記録層に対するトラッキング制御がオンされることになり、この動作はトラック引き込み動作と呼ばれる。 As a result, the R_TON signal is a signal for instructing on / off of tracking control for the recording layer. The switch 1517 functions as a switch for switching on / off the tracking control for the recording layer. When the R_TON signal is switched from Low to High, tracking control for the recording layer is turned on, and this operation is called a track pull-in operation.
　スイッチ１５１７から出力される記録層トラッキング駆動信号Ｒ＿ＴＲＤは、セレクタ１５１８に入力される。セレクタ１５１８においては、システム制御回路１５０１の出力するＯＬ＿ＴＳＥＬ信号に基づき、Ｒ＿ＴＲＤ信号もしくは後述するＳ＿ＴＲＤ信号のいずれかを選択して出力する。ここでは記録層光学系について説明しているため、セレクタ１５１８ではＲ＿ＴＲＤ信号が出力されるものとして説明する。 The recording layer tracking drive signal R_TRD output from the switch 1517 is input to the selector 1518. The selector 1518 selects and outputs either the R_TRD signal or the S_TRD signal described later based on the OL_TSEL signal output from the system control circuit 1501. Here, since the recording layer optical system is described, it is assumed that the selector 1518 outputs an R_TRD signal.
　トラッキング駆動電圧生成回路１５１９は、システム制御回路１５０１からの指令信号により、所定の電圧を出力する。トラッキング駆動電圧生成回路１５１９は例えば、トラックジャンプ時のジャンプ電圧を出力する。またトラッキング駆動電圧生成回路１５１９にはスピンドル駆動回路１０８の出力するＦＧ信号も入力されており、ＦＧ信号を用いて光ディスク１０１の回転に同期してトラックジャンプ時のジャンプ電圧を出力することで、光ディスク１０１の同一のトラックを追従し続ける動作を行うこともできる。トラッキング駆動電圧生成回路１５１９は例えば、一般的なＣＰＵを用いることができる。 The tracking drive voltage generation circuit 1519 outputs a predetermined voltage in response to a command signal from the system control circuit 1501. For example, the tracking drive voltage generation circuit 1519 outputs a jump voltage at the time of track jump. The tracking drive voltage generation circuit 1519 also receives an FG signal output from the spindle drive circuit 108, and outputs a jump voltage at the time of track jump in synchronization with the rotation of the optical disk 101 using the FG signal. An operation of continuing to follow the same track 101 can also be performed. As the tracking drive voltage generation circuit 1519, for example, a general CPU can be used.
　加算器１５２０は、セレクタ１５１８の出力信号とトラッキング駆動電圧生成回路１５１９の出力信号を加算し、対物レンズ駆動トラッキング駆動信号ＯＬ＿ＴＲＤとしてアクチュエータ駆動回路１０９に出力する。 The adder 1520 adds the output signal of the selector 1518 and the output signal of the tracking drive voltage generation circuit 1519 and outputs the result to the actuator drive circuit 109 as an objective lens drive tracking drive signal OL_TRD.
　アクチュエータ駆動回路１０９は、対物レンズ駆動トラッキング駆動信号ＯＬ＿ＴＲＤに従ってアクチュエータ１３１２を半径方向に駆動することで、対物レンズ１３１１の位置を変位させ、記録層トラック上、もしくはサーボ層トラック上にレーザスポットが照射されるようにトラッキング制御を行う。このように、本実施例におけるアクチュエータ駆動回路１０９は、フォーカス方向に駆動する回路とトラッキング方向に駆動する回路を包含したものである。 The actuator drive circuit 109 drives the actuator 1312 in the radial direction according to the objective lens drive tracking drive signal OL_TRD, thereby displacing the position of the objective lens 1311 and irradiating the laser spot on the recording layer track or the servo layer track. Tracking control. Thus, the actuator drive circuit 109 in this embodiment includes a circuit that drives in the focus direction and a circuit that drives in the tracking direction.
　以上で説明したように、本実施例の光ディスク装置１０１における記録層に対するトラッキング制御は、セレクタ１５１３でのＲ＿ＴＥ信号の選択状態により、２種類存在する。Ｒ＿ＴＥ信号としてＲ＿ＳｕｂＴＥを用いる場合の制御を、以下では記録層ＳｕｂＳｐｏｔトラッキング制御と呼ぶ。これに対し、Ｒ＿ＴＥ信号としてＲ＿ＭａｉｎＴＥを用いる場合の制御を、以下では記録層ＭａｉｎＳｐｏｔトラッキング制御と呼ぶ。 As described above, there are two types of tracking control for the recording layer in the optical disc apparatus 101 of this embodiment depending on the selection state of the R_TE signal in the selector 1513. Control in the case of using R_SubTE as the R_TE signal is hereinafter referred to as recording layer SubSpot tracking control. On the other hand, control in the case of using R_MainTE as the R_TE signal is hereinafter referred to as recording layer MainSpot tracking control.
　次に、サーボ層光学系について説明する。記録層光学系と同様に、レーザパワー制御回路１３０１はシステム制御回路１５０１によって制御されており、レーザダイオード１３１５を駆動する電流を出力する。レーザダイオード１３１５は例えば波長６５０ｎｍのレーザ光Ｓ＿ＬＢを出射する。レーザ光Ｓ＿ＬＢの一部は、コリメータレンズ１３１６、ビームスプリッタ１３１７、集光レンズ１３１８を経て、パワーモニタ１３１９にてパワーがモニタされる。モニタしたパワーをＳ＿ＰＭ信号としてシステム制御回路１５０１にフィードバックすることで、光ディスク１０２のサーボ層に集光するレーザ光Ｓ＿ＬＢの強度が、たとえば３ｍＷなど所望のパワーに保持される。ビームスプリッタ１３１７を透過したレーザ光Ｓ＿ＬＢは、偏光ビームスプリッタ１３２０を透過し、リレーレンズ１３２１にて収束・発散の制御が行われる。リレーレンズ１３２１を経たレーザ光Ｓ＿ＬＢは、ダイクロイックミラー１３０８にて反射し、１／４波長板１３１０を経て、対物レンズ１３１１により光ディスク１０２のサーボ層にレーザスポットＳ＿ＬＳとして集光する。光ディスク１０２にて反射したレーザ光Ｓ＿ＬＢを偏光ビームスプリッタ１３２０にて反射し、集光レンズ１３２２にてディテクタ１３２３に集光する。 Next, the servo layer optical system will be described. Similar to the recording layer optical system, the laser power control circuit 1301 is controlled by the system control circuit 1501 and outputs a current for driving the laser diode 1315. The laser diode 1315 emits laser light S_LB having a wavelength of 650 nm, for example. Part of the laser light S_LB passes through a collimator lens 1316, a beam splitter 1317, and a condenser lens 1318, and the power is monitored by a power monitor 1319. By feeding back the monitored power to the system control circuit 1501 as an S_PM signal, the intensity of the laser light S_LB focused on the servo layer of the optical disc 102 is maintained at a desired power such as 3 mW. The laser beam S_LB that has passed through the beam splitter 1317 passes through the polarization beam splitter 1320, and is controlled to converge and diverge by the relay lens 1321. The laser beam S_LB that has passed through the relay lens 1321 is reflected by the dichroic mirror 1308, passes through the quarter-wave plate 1310, and is condensed as a laser spot S_LS on the servo layer of the optical disc 102 by the objective lens 1311. The laser beam S_LB reflected by the optical disk 102 is reflected by the polarization beam splitter 1320 and condensed on the detector 1323 by the condenser lens 1322.
　ディテクタ１３２３ではレーザ光の強度を検出し、これに応じた信号を信号処理回路１０６に出力する。信号処理回路１０６は、ディテクタ１３２３から出力されるサーボ層にウォブルして形成されたトラックに対応した信号により光ディスク１０２の回転を制御するための同期信号、記録或いは再生を行う際の基準となるクロック信号を生成するとともに、レーザスポットＳ＿ＬＳが追従しているディスク上の位置に対応したアドレスを再生してシステム制御回路１５０１に出力する。 The detector 1323 detects the intensity of the laser beam and outputs a signal corresponding to the intensity to the signal processing circuit 106. The signal processing circuit 106 is a synchronization signal for controlling the rotation of the optical disc 102 based on a signal corresponding to a track formed by wobbling the servo layer output from the detector 1323, and a clock used as a reference for recording or reproduction. A signal is generated, and an address corresponding to the position on the disc that the laser spot S_LS is following is reproduced and output to the system control circuit 1501.
　サーボエラー信号生成回路１０４において、サーボ層フォーカスエラー信号生成回路１４０４は、ディテクタ１３２３から出力された信号から、光ディスク１０２のサーボ層とレーザスポットＳ＿ＬＳの焦点位置とのずれ量を示すサーボ層フォーカスエラー信号Ｓ＿ＦＥを生成する。またディテクタ１３２３から出力された信号はサーボ層トラッキングエラー信号生成回路１４０２にも入力され、サーボ層トラックとレーザスポットＳ＿ＬＳの位置のずれ量を示すサーボ層トラッキングエラー信号Ｓ＿ＴＥを生成する。 In the servo error signal generation circuit 104, a servo layer focus error signal generation circuit 1404 indicates a servo layer focus error signal indicating an amount of deviation between the servo layer of the optical disc 102 and the focal position of the laser spot S_LS from the signal output from the detector 1323. S_FE is generated. The signal output from the detector 1323 is also input to the servo layer tracking error signal generation circuit 1402 to generate a servo layer tracking error signal S_TE indicating the amount of displacement between the servo layer track and the laser spot S_LS.
　サーボエラー信号生成回路１０４で生成されたエラー信号は信号処理回路１０５に入力され、サーボ層に対するフォーカス制御、トラッキング制御が行われる。 The error signal generated by the servo error signal generation circuit 104 is input to the signal processing circuit 105, and focus control and tracking control for the servo layer are performed.
　サーボ層フォーカス制御回路１５０６は、システム制御回路１５０１からの指令信号により、サーボ層フォーカスエラー信号Ｓ＿ＦＥに対してゲインと位相の補償を行い、サーボ層に対するフォーカス制御を行うための駆動信号を出力する。サーボ層フォーカス制御回路１５０６から出力された駆動信号は、スイッチ１５０７、加算器１５０９を介してリレーレンズ駆動回路１１０に入力される。 Servo layer focus control circuit 1506 performs gain and phase compensation for servo layer focus error signal S_FE in response to a command signal from system control circuit 1501, and outputs a drive signal for performing focus control on the servo layer. The drive signal output from the servo layer focus control circuit 1506 is input to the relay lens drive circuit 110 via the switch 1507 and the adder 1509.
　スイッチ１５０７はシステム制御回路１５０１の出力するＳ＿ＦＯＮ信号に基づき、サーボ層フォーカス制御回路１５０６の出力信号もしくは基準電位Ｖｒｅｆを選択して出力する。Ｓ＿ＦＯＮ信号としてＨｉｇｈレベルが入力されると、スイッチ１５０７は端子ｃを選択して、サーボ層フォーカス制御回路１５０６の出力信号が加算器１５０９を介してリレーレンズ駆動回路１１０に出力される。一方でＳ＿ＦＯＮ信号としてＬｏｗレベルが入力されると、スイッチ１５０７は端子ｄを選択し、基準電位Ｖｒｅｆを出力する。 The switch 1507 selects and outputs the output signal of the servo layer focus control circuit 1506 or the reference potential Vref based on the S_FON signal output from the system control circuit 1501. When the high level is input as the S_FON signal, the switch 1507 selects the terminal c, and the output signal of the servo layer focus control circuit 1506 is output to the relay lens driving circuit 110 via the adder 1509. On the other hand, when the Low level is input as the S_FON signal, the switch 1507 selects the terminal d and outputs the reference potential Vref.
　この結果、Ｓ＿ＦＯＮ信号はサーボ層に対するフォーカス制御のオン・オフを指示する信号となる。またスイッチ１５０７は、サーボ層に対するフォーカス制御のオン、オフを切り替えるスイッチとして機能する。Ｓ＿ＦＯＮ信号がＬｏｗからＨｉｇｈに切り替わることでサーボ層に対するフォーカス制御がオンされることになり、この動作はフォーカス引き込み動作と呼ばれる。 As a result, the S_FON signal is a signal for instructing on / off of focus control for the servo layer. The switch 1507 functions as a switch for switching on and off the focus control for the servo layer. When the S_FON signal is switched from Low to High, the focus control for the servo layer is turned on, and this operation is called a focus pull-in operation.
　サーボ層フォーカス駆動電圧生成回路１５０８は、システム制御回路１５０１からの指令信号により、所定の電圧を出力する。サーボ層フォーカス駆動電圧生成回路１５０８は例えば、フォーカススイープ動作におけるスイープ電圧や、フォーカスジャンプ時のジャンプ電圧を出力する。サーボ層フォーカス駆動電圧生成回路１５０８は例えば、一般的なＣＰＵを用いることができる。 Servo layer focus drive voltage generation circuit 1508 outputs a predetermined voltage in response to a command signal from system control circuit 1501. The servo layer focus drive voltage generation circuit 1508 outputs, for example, a sweep voltage in the focus sweep operation and a jump voltage at the time of focus jump. As the servo layer focus drive voltage generation circuit 1508, for example, a general CPU can be used.
　加算器１５０９は、スイッチ１５０７の出力信号とサーボ層フォーカス駆動電圧生成回路１５０８の出力信号を加算し、サーボ層フォーカス駆動信号Ｓ＿ＦＯＤとしてリレーレンズ駆動回路１１０に出力する。 The adder 1509 adds the output signal of the switch 1507 and the output signal of the servo layer focus drive voltage generation circuit 1508, and outputs the result to the relay lens drive circuit 110 as the servo layer focus drive signal S_FOD.
　リレーレンズ駆動回路１１０は、サーボ層フォーカス駆動信号Ｓ＿ＦＯＤに従ってリレーレンズ１３２１を駆動することで、レーザ光Ｓ＿ＬＢの焦点位置をフォーカス方向に変位させ、レーザ光Ｓ＿ＬＢがサーボ層に合焦するようにフォーカス制御を行う。本明細書では、この制御のことをサーボ層フォーカス制御と呼ぶ。 The relay lens drive circuit 110 drives the relay lens 1321 according to the servo layer focus drive signal S_FOD, thereby displacing the focal position of the laser light S_LB in the focus direction, and focus control so that the laser light S_LB is focused on the servo layer. I do. In this specification, this control is called servo layer focus control.
　サーボ層トラッキング制御回路１５１０は、システム制御回路１５０１からの指令信号により、サーボ層トラッキングエラー信号Ｓ＿ＴＥに対してゲインと位相の補償を行い、記録層に対するトラッキング制御を行うための駆動信号を出力する。サーボ層トラッキング制御回路１５１０から出力された駆動信号は、スイッチ１５１１、セレクタ１５１８、加算器１５２０を介してアクチュエータ駆動回路１０９に入力され、同時にスイッチ１５１１、セレクタ１５１７を介してリレーレンズ駆動回路１１０に入力される。 Servo layer tracking control circuit 1510 performs gain and phase compensation for servo layer tracking error signal S_TE in response to a command signal from system control circuit 1501, and outputs a drive signal for performing tracking control on the recording layer. The drive signal output from the servo layer tracking control circuit 1510 is input to the actuator drive circuit 109 via the switch 1511, the selector 1518, and the adder 1520, and simultaneously input to the relay lens drive circuit 110 via the switch 1511 and the selector 1517. Is done.
　スイッチ１５１１はシステム制御回路１５０１の出力するＳ＿ＴＯＮ信号に基づき、サーボ層トラッキング制御回路１５１０の出力信号もしくは基準電位Ｖｒｅｆを選択して、サーボ層トラッキング駆動信号Ｓ＿ＴＲＤとして出力する。Ｓ＿ＴＯＮ信号としてＨｉｇｈレベルが入力されると、スイッチ１５１１は端子ｉを選択して、サーボ層トラッキング制御回路１５１０の出力信号が出力される。一方でＳ＿ＴＯＮ信号としてＬｏｗレベルが入力されると、スイッチ１５１１は端子ｊを選択し、基準電位Ｖｒｅｆを出力する。 The switch 1511 selects the output signal of the servo layer tracking control circuit 1510 or the reference potential Vref based on the S_TON signal output from the system control circuit 1501, and outputs it as the servo layer tracking drive signal S_TRD. When the high level is input as the S_TON signal, the switch 1511 selects the terminal i, and the output signal of the servo layer tracking control circuit 1510 is output. On the other hand, when the Low level is input as the S_TON signal, the switch 1511 selects the terminal j and outputs the reference potential Vref.
　この結果、Ｓ＿ＴＯＮ信号はサーボ層に対するトラッキング制御のオン・オフを指示する信号となる。またスイッチ１５１１は、サーボ層に対するトラッキング制御のオン、オフを切り替えるスイッチとして機能する。Ｓ＿ＴＯＮ信号がＬｏｗからＨｉｇｈに切り替わることでサーボ層に対するトラッキング制御がオンされることになり、この動作はトラック引き込み動作と呼ばれる。 As a result, the S_TON signal is a signal for instructing on / off of tracking control for the servo layer. The switch 1511 functions as a switch for switching on / off of tracking control for the servo layer. When the S_TON signal is switched from Low to High, tracking control for the servo layer is turned on, and this operation is called a track pull-in operation.
　スイッチ１５１１から出力されるサーボ層トラッキング駆動信号Ｓ＿ＴＲＤは、セレクタ１５１８及びセレクタ１５１２に入力される。 Servo layer tracking drive signal S_TRD output from switch 1511 is input to selector 1518 and selector 1512.
　セレクタ１５１８においては、システム制御回路１５０１の出力するＯＬ＿ＴＳＥＬ信号に基づき、Ｒ＿ＴＲＤ信号もしくはＳ＿ＴＲＤ信号のいずれかを選択して対物レンズ駆動トラッキング駆動信号ＯＬ＿ＴＲＤとして出力する。ＯＬ＿ＴＳＥＬ信号としてＨｉｇｈレベルが入力されると、セレクタ１５１８は端子ｋを選択してＲ＿ＴＲＤ信号を出力し、ＯＬ＿ＴＳＥＬ信号としてＬｏｗレベルが入力されると、セレクタ１５１８は端子ｌを選択してＳ＿ＴＲＤ信号を出力する。 The selector 1518 selects either the R_TRD signal or the S_TRD signal based on the OL_TSEL signal output from the system control circuit 1501 and outputs it as the objective lens drive tracking drive signal OL_TRD. When the High level is input as the OL_TSEL signal, the selector 1518 selects the terminal k and outputs the R_TRD signal. When the Low level is input as the OL_TSEL signal, the selector 1518 selects the terminal l and outputs the S_TRD signal. To do.
　またセレクタ１５１２においては、システム制御回路１５０１の出力するＲＬ＿ＴＳＥＬ信号に基づき、Ｓ＿ＴＲＤ信号もしくは基準電位Ｖｒｅｆのいずれかを選択してリレーレンズ駆動トラッキング駆動信号ＲＬ＿ＴＲＤとして出力する。ＲＬ＿ＴＳＥＬ信号としてＨｉｇｈレベルが入力されると、セレクタ１５１２は端子ｇを選択してＳ＿ＴＲＤ信号を出力し、ＲＬ＿ＴＳＥＬ信号としてＬｏｗレベルが入力されると、セレクタ１５１２は端子ｈを選択して基準電位Ｖｒｅｆを出力する。 Also, the selector 1512 selects either the S_TRD signal or the reference potential Vref based on the RL_TSEL signal output from the system control circuit 1501 and outputs it as the relay lens drive tracking drive signal RL_TRD. When the High level is input as the RL_TSEL signal, the selector 1512 selects the terminal g and outputs the S_TRD signal. When the Low level is input as the RL_TSEL signal, the selector 1512 selects the terminal h and sets the reference potential Vref. Output.
　リレーレンズ駆動回路１１０は、トラッキング駆動信号ＲＬ＿ＴＲＤに従ってリレーレンズ１３２１を駆動することで、レーザ光Ｓ＿ＬＢの焦点位置を半径方向に変位させ、サーボ層トラック上にレーザスポットが照射されるようにトラッキング制御を行う。このように、本実施例におけるリレーレンズ駆動回路１１０は、レーザ光Ｓ＿ＬＢの焦点位置をフォーカス方向に駆動する回路とトラッキング方向に駆動する回路を包含したものである。 The relay lens drive circuit 110 drives the relay lens 1321 in accordance with the tracking drive signal RL_TRD, thereby displacing the focal position of the laser light S_LB in the radial direction and performing tracking control so that the laser spot is irradiated onto the servo layer track. Do. As described above, the relay lens driving circuit 110 in this embodiment includes a circuit for driving the focal position of the laser light S_LB in the focus direction and a circuit for driving in the tracking direction.
　このように、サーボ層トラッキング駆動信号Ｓ＿ＴＲＤは、ＲＬ＿ＴＳＥＬ信号及びＯＬ＿ＴＳＥＬ信号により、アクチュエータ駆動回路１０９もしくはリレーレンズ駆動回路１１０へと入力される。また、両方へ同時に入力されることはないものとする。言い換えると、本実施例の光ディスク装置１０１におけるサーボ層に対するトラッキング制御は、アクチュエータ１３１２を駆動する回路構成と、リレーレンズ１３２１を駆動する回路構成とを切り替えることができる。 Thus, the servo layer tracking drive signal S_TRD is input to the actuator drive circuit 109 or the relay lens drive circuit 110 by the RL_TSEL signal and the OL_TSEL signal. Also, it is assumed that they are not input to both at the same time. In other words, the tracking control for the servo layer in the optical disc apparatus 101 of this embodiment can be switched between a circuit configuration for driving the actuator 1312 and a circuit configuration for driving the relay lens 1321.
　サーボ層に対するトラッキング制御に関して、アクチュエータ１３１２を駆動して行う場合の制御を、以下では対物レンズ駆動サーボ層トラッキング制御と呼ぶ。これに対しリレーレンズ１３２１を駆動して行う場合の制御を、以下ではリレーレンズ駆動サーボ層トラッキング制御と呼ぶ。アクチュエータ１３１２を駆動して行う場合の制御を、以下ではリレーレンズ駆動サーボ層トラッキング制御と呼ぶ。 Regarding the tracking control for the servo layer, the control performed by driving the actuator 1312 is hereinafter referred to as objective lens driving servo layer tracking control. On the other hand, the control in the case where the relay lens 1321 is driven is hereinafter referred to as relay lens driving servo layer tracking control. Control performed when the actuator 1312 is driven is hereinafter referred to as relay lens drive servo layer tracking control.
　続いて、記録層とサーボ層で共通な部分について説明する。 Next, the common part between the recording layer and the servo layer will be described.
　スライダ制御回路１５２１では、システム制御回路１５０１からの指令信号により、セレクタ１５１８の出力信号の平均値に基づいてスライダモータ１１２を駆動するスライダ駆動信号ＳＬＤを出力する。このＳＬＤ信号に従ってスライダ駆動回路１１３によりスライダモータ１１２を駆動し、アクチュエータ１３１２がディスク半径方向可動範囲の中心位置近傍で動作するように光ピックアップ１０３をディスク半径方向に移送する。 The slider control circuit 1521 outputs a slider drive signal SLD for driving the slider motor 112 based on the average value of the output signals of the selector 1518 in response to a command signal from the system control circuit 1501. The slider motor 112 is driven by the slider drive circuit 113 in accordance with this SLD signal, and the optical pickup 103 is moved in the disk radial direction so that the actuator 1312 operates in the vicinity of the center position of the movable range in the disk radial direction.
　次に、信号処理回路１０６の働きについて説明する。記録層にデータを記録する場合は、サーボ層トラックをレーザスポットＳ＿ＭａｉｎＬＳが追従するようにトラッキングサーボ制御が行われる。この結果、ディテクタ１３２３からサーボ層からの再生信号が出力されて、信号処理回路１０６に入力される。また、ホスト１１４から入力された記録層に記録するデータ及びデータを記録するディスク上の位置に対応したアドレス情報がシステム制御回路１５０１から信号処理回路１０６に出力される。信号処理回路１０６では入力されたデータ及びアドレス情報をサーボ層から再生された基準クロック信号に基づいて所定の方式で変調し、レーザパワー制御回路１３０１に出力する。レーザパワー制御回路１３０１は信号処理回路１０６の出力に応じた駆動電流をレーザダイオード１３０２に出力し、レーザダイオード１３０２が対応した強度でレーザ光Ｒ＿ＬＢを出射することで光ディスク１０２の記録層に記録が行われる。これにより、ガイド層に形成されたトラックに追従しながら記録層に記録を行うため、ガイド層のトラックのスパイラルと同じ軌跡で記録層に情報の記録が行われる。例えばガイド層のトラックが内周から外周に向かってスパイラル状に形成されていると、記録層により記録される軌跡は全ての層が同じように内周から外周に向かってスパイラル状に形成される。 Next, the operation of the signal processing circuit 106 will be described. When data is recorded on the recording layer, tracking servo control is performed so that the laser spot S_MainLS follows the servo layer track. As a result, a reproduction signal from the servo layer is output from the detector 1323 and input to the signal processing circuit 106. Further, data to be recorded on the recording layer input from the host 114 and address information corresponding to the position on the disk where the data is recorded are output from the system control circuit 1501 to the signal processing circuit 106. The signal processing circuit 106 modulates the input data and address information by a predetermined method based on the reference clock signal reproduced from the servo layer, and outputs it to the laser power control circuit 1301. The laser power control circuit 1301 outputs a drive current corresponding to the output of the signal processing circuit 106 to the laser diode 1302, and the laser diode 1302 emits the laser beam R_LB with a corresponding intensity, so that recording is performed on the recording layer of the optical disc 102. Is called. As a result, recording is performed on the recording layer while following the tracks formed on the guide layer, so that information is recorded on the recording layer along the same locus as the spiral of the track of the guide layer. For example, when the guide layer track is formed in a spiral shape from the inner periphery to the outer periphery, the track recorded by the recording layer is formed in a spiral shape from the inner periphery to the outer periphery in the same manner. .
　また、記録層に記録された情報を再生する場合には、記録層に記録された情報の軌跡からなるトラックをレーザスポットＲ＿ＭａｉｎＬＳが追従するようにトラッキングサーボ制御が行われる。この結果、ディテクタ１３１４から記録層からの再生信号が出力されて、信号処理回路１０６に入力される。信号処理回路１０６では入力された再生信号から光ディスク１０２の回転を制御するための同期信号、再生を行う際の基準となるクロック信号を生成する。また、信号処理回路１０６は再生信号に対して増幅、等化、復号などの処理を行い、復号したデータ及びデータのディスク上の位置に対応したアドレス情報をシステム制御回路１５０１に出力する。システム制御回路１５０１は再生したデータをホスト１１４に出力する。 Further, when reproducing information recorded on the recording layer, tracking servo control is performed so that the laser spot R_MainLS follows a track formed by the locus of information recorded on the recording layer. As a result, a reproduction signal from the recording layer is output from the detector 1314 and input to the signal processing circuit 106. The signal processing circuit 106 generates a synchronization signal for controlling the rotation of the optical disc 102 and a clock signal serving as a reference for reproduction from the input reproduction signal. The signal processing circuit 106 performs processing such as amplification, equalization, and decoding on the reproduction signal, and outputs the decoded data and address information corresponding to the position of the data on the disk to the system control circuit 1501. The system control circuit 1501 outputs the reproduced data to the host 114.
　信号処理回路１０６から出力される同期信号とスピンドル駆動手段１０８から出力されるＦＧ信号はスピンドル制御回路１５２２に入力される。スピンドル制御回路１５２２ではシステム制御回路１５０１からの指令信号により、光ディスク１０２を角速度一定で回転させる場合にはスピンドルモータ１０７の回転速度に対応した周波数のＦＧ信号に基づいたスピンドル駆動信号ＳＰＤを出力し、光ディスク１０２を線速度一定で回転させる場合にはサーボ層もしくは記録層から再生された同期信号に基づいたスピンドル駆動信号ＳＰＤを出力する。スピンドル駆動回路１０８ではＳＰＤ信号に応じてスピンドルモータ１０７を駆動することで光ディスクの回転数が所定の値となるようにスピンドル制御が行われる。 The synchronization signal output from the signal processing circuit 106 and the FG signal output from the spindle driving means 108 are input to the spindle control circuit 1522. The spindle control circuit 1522 outputs a spindle drive signal SPD based on an FG signal having a frequency corresponding to the rotation speed of the spindle motor 107 when the optical disk 102 is rotated at a constant angular speed according to a command signal from the system control circuit 1501. When the optical disk 102 is rotated at a constant linear velocity, a spindle drive signal SPD based on a synchronization signal reproduced from the servo layer or the recording layer is output. The spindle drive circuit 108 performs spindle control so that the rotational speed of the optical disk becomes a predetermined value by driving the spindle motor 107 in accordance with the SPD signal.
　図６に本実施例の光ディスク装置１０１に光ディスク１０２が挿入された時のセットアップ処理のフローチャートを示す。 FIG. 6 shows a flowchart of the setup process when the optical disc 102 is inserted into the optical disc apparatus 101 of the present embodiment.
　光ディスク装置１０１に光ディスク１０２が挿入されると、セットアップ処理が開始される（ステップＳ６０１）。セットアップ処理において光ディスク装置はまず、ディスク認識処理を行う（ステップＳ６０２）。ディスク認識処理においては、ディスクの有無の確認やディスク種別の確認を行う。 When the optical disc 102 is inserted into the optical disc apparatus 101, a setup process is started (step S601). In the setup process, the optical disk apparatus first performs a disk recognition process (step S602). In the disc recognition process, the presence / absence of the disc and the disc type are confirmed.
　この動作は例えば、システム制御回路１３０１がレーザパワー制御回路１３０１に指示していずれかのレーザダイオードを発光させ、同時に、システム制御回路１３０１が記録層フォーカス駆動電圧生成回路１５０４に指示して対物レンズ１３１１をディスク面に垂直な方向に駆動することで実現できる。光ディスク１０１にレーザ光を照射された結果、いずれかのディテクタによって反射光が検出され、検出された信号を用いて認識を行うことができる。 In this operation, for example, the system control circuit 1301 instructs the laser power control circuit 1301 to cause one of the laser diodes to emit light, and at the same time, the system control circuit 1301 instructs the recording layer focus drive voltage generation circuit 1504 to objective lens 1311. Can be realized by driving in a direction perpendicular to the disk surface. As a result of irradiating the optical disc 101 with laser light, reflected light is detected by any detector, and recognition can be performed using the detected signal.
　次に光ディスク装置は、収差補正素子駆動処理を行う（ステップＳ６０３）。これは後述するフォーカス引き込み処理のための準備であり、所定の収差補正量になるように収差補正素子１３０９を駆動する。 Next, the optical disc apparatus performs an aberration correction element driving process (step S603). This is preparation for a focus pull-in process, which will be described later, and the aberration correction element 1309 is driven so that a predetermined aberration correction amount is obtained.
　次に光ディスク装置は、リレーレンズ駆動処理を行う（ステップＳ６０４）。これは後述するフォーカス引き込み処理のための準備であり、リレーレンズの位置が所定の位置になるようにリレーレンズ１３２１を駆動する。 Next, the optical disc apparatus performs a relay lens driving process (step S604). This is preparation for a focus pull-in process described later, and the relay lens 1321 is driven so that the position of the relay lens becomes a predetermined position.
　ステップＳ６０４の後、光ディスク１０１の記録層に対してフォーカス引き込み処理を行う（ステップＳ６０５）。この処理では、システム制御回路１３０１は記録層フォーカス駆動電圧生成回路１５０４に指示して所定のパターンの電圧を出力すると共に、Ｒ＿ＦＯＮ信号をＬｏｗレベルからＨｉｇｈレベルに変更する。記録層フォーカス駆動電圧生成回路１５０４により対物レンズ１３１１と一体で動作するように構成されたアクチュエータ１３１２がディスク面に垂直な方向に駆動され、Ｒ＿ＦＯＮ信号のレベル変更によりスイッチ１３１１が切り替わって記録層フォーカス制御がオンされる。 After step S604, focus pull-in processing is performed on the recording layer of the optical disc 101 (step S605). In this process, the system control circuit 1301 instructs the recording layer focus drive voltage generation circuit 1504 to output a voltage having a predetermined pattern, and changes the R_FON signal from Low level to High level. An actuator 1312 configured to operate integrally with the objective lens 1311 is driven by the recording layer focus drive voltage generation circuit 1504 in a direction perpendicular to the disk surface, and the switch 1311 is switched by changing the level of the R_FON signal to control the recording layer focus. Is turned on.
　ステップＳ６０５の後、光ディスク１０１のサーボ層に対してフォーカス引き込み処理を行う（ステップＳ６０６）。この処理では、システム制御回路１３０１はサーボ層フォーカス駆動電圧生成回路１５０８に指示して所定のパターンの電圧を出力すると共に、Ｓ＿ＦＯＮ信号をＬｏｗレベルからＨｉｇｈレベルに変更する。サーボ層フォーカス駆動電圧生成回路１５０８によりリレーレンズ１３１１が駆動されてレーザ光Ｓ＿ＬＢの焦点位置をフォーカス方向に変位し、Ｓ＿ＦＯＮ信号のレベル変更によりスイッチ１３１１が切り替わってサーボ層フォーカス制御がオンされる。 After step S605, focus pull-in processing is performed on the servo layer of the optical disc 101 (step S606). In this processing, the system control circuit 1301 instructs the servo layer focus drive voltage generation circuit 1508 to output a predetermined pattern voltage, and changes the S_FON signal from the Low level to the High level. The relay lens 1311 is driven by the servo layer focus drive voltage generation circuit 1508 to displace the focus position of the laser light S_LB in the focus direction, and the switch 1311 is switched by changing the level of the S_FON signal, and the servo layer focus control is turned on.
　次に光ディスク装置は、光ディスク１０１の記録層トラックに対してトラック引き込み処理を行う（ステップＳ６０７）。この処理では、システム制御回路１３０１はトラッキング制御に関する制御信号を変更した上で、Ｒ＿ＴＯＮ信号をＬｏｗレベルからＨｉｇｈレベルに変更する。これによりスイッチ１３１１が切り替わり、記録層トラッキング制御がオンされる。 Next, the optical disc apparatus performs track pull-in processing on the recording layer track of the optical disc 101 (step S607). In this process, the system control circuit 1301 changes the control signal related to tracking control, and then changes the R_TON signal from the Low level to the High level. As a result, the switch 1311 is switched and the recording layer tracking control is turned on.
　次に挿入された光ディスク１０１に対して、光ディスク装置内の各種パラメータを適正化するための調整処理を行う（ステップＳ６０８）。各種パラメータとは、たとえば記録層フォーカス制御回路１５０２や記録層トラッキング制御回路１５１６の内部に含まれる増幅器の増幅率を光ディスク１０１の反射率にあわせて調節することなどが挙げられる。 Next, adjustment processing for optimizing various parameters in the optical disc apparatus is performed on the inserted optical disc 101 (step S608). Examples of the various parameters include adjusting the amplification factor of the amplifier included in the recording layer focus control circuit 1502 and the recording layer tracking control circuit 1516 in accordance with the reflectance of the optical disc 101.
　ステップＳ６０８を行った後、光ディスク１０１に記録された管理情報を読み出す、管理情報読み出し処理を行う（ステップＳ６０９）。 After performing step S608, a management information reading process for reading management information recorded on the optical disc 101 is performed (step S609).
　ステップＳ６０９が完了すると、セットアップ処理が終了する（ステップＳ６１０）。これにより、ホストからの指示を受けて情報の記録または再生を行うことが可能な状態となる。 When step S609 is completed, the setup process ends (step S610). Thus, it becomes possible to record or reproduce information in response to an instruction from the host.
　なお調整処理Ｓ６０７のタイミングはこれに限るものではなく、一部の調整処理を、フォーカス引き込み処理Ｓ６０５の前、または管理情報読み出し処理Ｓ６０９の後などに行ってもよい。 Note that the timing of the adjustment process S607 is not limited to this, and part of the adjustment process may be performed before the focus pull-in process S605 or after the management information read process S609.
　ここで、セットアップ処理が終了した状態の、光ディスク装置１０１のサーボ系の回路構成について説明する。図８から図１０は、各種動作状態における光ディスク装置１０１のトラッキング制御系及びフォーカス制御系の状態を説明するための表である。各表において、動作状態の欄に記載されている名称については、後述する。Ｎｏ欄に示したように、本実施例における光ディスク装置１０１のサーボ系の回路構成は、動作状態によって４つのパターンが存在する。Ｎｏ欄で示した番号を用い、Ｎｏ１の回路構成で動作する状態のことを状態１と称することにする。 Here, the circuit configuration of the servo system of the optical disc apparatus 101 after the setup process has been completed will be described. 8 to 10 are tables for explaining the states of the tracking control system and the focus control system of the optical disc apparatus 101 in various operation states. In each table, names described in the column of the operation state will be described later. As shown in the No column, the servo system circuit configuration of the optical disc apparatus 101 in this embodiment has four patterns depending on the operating state. Using the numbers shown in the No column, the state operating with the circuit configuration of No. 1 will be referred to as state 1.
　図８は、各種動作状態におけるトラッキング制御系及びフォーカス制御系の動作状態と、本明細書において定義した名称を示す表である。各動作状態に対して破線にて２段に分けて記載してあるのは、上段が記録層に対する制御、下段がサーボ層に対する制御を示している。また表中、「－」で記載してある部分は、制御を行わないことを示す。例えば状態１に関しては、記録層に対するフォーカス制御は行うが、記録層に対するトラッキング制御は行わないことを意味する。 FIG. 8 is a table showing the operating states of the tracking control system and the focus control system in various operating states and the names defined in this specification. For each operation state, two stages are indicated by broken lines. The upper part shows the control for the recording layer, and the lower part shows the control for the servo layer. Also, in the table, the part indicated by “-” indicates that control is not performed. For example, regarding state 1, it means that focus control is performed on the recording layer, but tracking control is not performed on the recording layer.
　図９は、図８で示した制御系の回路構成を実現するためにシステム制御回路１５０１が出力する制御信号の値を示したものである。表中、「ＮｏＣａｒｅ」と記載してある部分は、ＨｉｇｈレベルであってもＬｏｗレベルであってもよいことを示す。 FIG. 9 shows values of control signals output from the system control circuit 1501 in order to realize the circuit configuration of the control system shown in FIG. In the table, the part described as “NoCare” indicates that it may be a high level or a low level.
　また図１０は、図９で示した制御信号の結果、対物レンズ及びリレーレンズのフォーカス駆動及びトラッキング駆動がどの駆動信号を用いて行われるかを示している。なお、対物レンズをトラッキング方向に駆動する記録層トラッキング制御に関しては、駆動信号の名称がＲ＿ＴＲＤ信号であったとしても、その前段にあるセレクタ１５１３における記録層トラッキングエラー信号Ｒ＿ＴＥの選択状態も重要である。そこで、対物レンズトラッキング駆動がＲ＿ＴＲＤ信号である場合には、Ｒ＿ＴＥ信号としてＲ＿ＳｕｂＴＥ信号、Ｒ＿ＭａｉｎＴＥ信号のいずれを選択しているかについても示している。 FIG. 10 shows which drive signal is used for focus driving and tracking driving of the objective lens and the relay lens as a result of the control signal shown in FIG. Regarding the recording layer tracking control for driving the objective lens in the tracking direction, even if the name of the drive signal is R_TRD signal, the selection state of the recording layer tracking error signal R_TE in the selector 1513 at the preceding stage is also important. . Thus, when the objective lens tracking drive is the R_TRD signal, it also indicates which of the R_SubTE signal and the R_MainTE signal is selected as the R_TE signal.
　セットアップ処理が終了した状態のサーボ系の回路構成は、図８乃至図１０における状態４に相当する。即ち図８に示すように、フォーカス制御に関しては記録層、サーボ層共に制御を行い、トラッキング制御に関しては記録層についてのみ制御を行う。また、その制御は記録層ＭａｉｎＳｐｏｔトラッキング制御である。 The circuit configuration of the servo system after the setup process is completed corresponds to the state 4 in FIGS. That is, as shown in FIG. 8, both the recording layer and the servo layer are controlled for focus control, and only the recording layer is controlled for tracking control. The control is recording layer MainSpot tracking control.
　図９に示すようにＲ＿ＦＯＮ信号、Ｓ＿ＦＯＮ信号は共にＨｉｇｈであるため、図１０に示すように対物レンズはＲ＿ＦＯＤ信号により、またリレーレンズはＳ＿ＦＯＤ信号により、フォーカス駆動される。 Since both the R_FON signal and the S_FON signal are high as shown in FIG. 9, the objective lens is driven by the R_FOD signal and the relay lens is driven by the S_FOD signal as shown in FIG.
　またトラッキング制御に関してはまず、図９に示すようにＲＬ＿ＴＤＥＬ信号がＬｏｗであることから、図１０に示すようにリレーレンズのトラッキング駆動は行われない。またＯＬ＿ＴＳＥＬ信号がＨｉｇｈでＲ＿ＴＯＮ信号がＨｉｇｈであることから、図１０に示すように対物レンズのトラッキング駆動はＲ＿ＴＲＤ信号によって行われる。更にこの時のＲ＿ＴＥＳＥＫ信号はＬｏｗであるため、Ｒ＿ＴＥ信号としてはＲ＿ＭａｉｎＴＥ信号が選択されている。即ち、図８に示すように記録層ＭａｉｎＳｐｏｔトラッキング制御が行われる。 Regarding tracking control, first, since the RL_TDEL signal is Low as shown in FIG. 9, the tracking driving of the relay lens is not performed as shown in FIG. Since the OL_TSEL signal is High and the R_TON signal is High, the objective lens is driven for tracking by the R_TRD signal as shown in FIG. Further, since the R_TESEK signal at this time is Low, the R_MainTE signal is selected as the R_TE signal. That is, the recording layer MainSpot tracking control is performed as shown in FIG.
　続いて図７に、ホスト１１４から情報の記録を指示された場合の本実施例の光ディスク装置１０１の記録処理のフローチャートを示す。 Subsequently, FIG. 7 shows a flowchart of the recording process of the optical disc apparatus 101 of the present embodiment when an instruction to record information is given from the host 114.
　ホスト１１４から情報の記録を指示されると、光ディスク装置１０１は記録処理を開始する（ステップＳ７０１）。記録処理において光ディスク装置１０１はまず、現在挿入されている光ディスクにとって、本記録処理による記録が初回の記録であるかどうかの確認を行う（ステップＳ７０２）。これは例えば、図６で示したセットアップ処理におけるステップＳ６０９の管理情報読み出し処理によって読み出された情報から判別することができる。または、実際にステップＳ７０２においてシーク動作を行い、管理情報等を読み出しに行ってもよい。 When the recording of information is instructed from the host 114, the optical disc apparatus 101 starts the recording process (step S701). In the recording process, the optical disk apparatus 101 first confirms whether or not the recording by the recording process is the first recording for the currently inserted optical disk (step S702). This can be determined, for example, from the information read out by the management information reading process in step S609 in the setup process shown in FIG. Alternatively, the seek operation may actually be performed in step S702 to read the management information and the like.
　現在挿入されている光ディスクにとって、本記録処理による記録が初回記録であった場合（ステップＳ７０２でＹｅｓの場合）、光ディスク装置１０１は対物レンズ駆動サーボ層トラッキング制御を開始する（ステップＳ７０３）。この処理においては、図８乃至図１０における動作状態を、状態４から状態１に切り替えることに相当する。 When the recording by this recording process is the first recording for the currently inserted optical disc (Yes in step S702), the optical disc apparatus 101 starts the objective lens drive servo layer tracking control (step S703). This process corresponds to switching the operation state in FIGS. 8 to 10 from state 4 to state 1.
　状態１は図８に示すように、フォーカス制御に関しては記録層、サーボ層共に制御を行い、トラッキング制御に関してはサーボ層についてのみ制御を行う。また、その制御は対物レンズ駆動サーボ層トラッキング制御である。 In state 1, as shown in FIG. 8, both the recording layer and the servo layer are controlled for focus control, and only the servo layer is controlled for tracking control. The control is objective lens driving servo layer tracking control.
　図９に示すようにＲ＿ＦＯＮ信号、Ｓ＿ＦＯＮ信号は共にＨｉｇｈであるため、図１０に示すように対物レンズはＲ＿ＦＯＤ信号により、またリレーレンズはＳ＿ＦＯＤ信号により、フォーカス駆動される。 Since both the R_FON signal and the S_FON signal are high as shown in FIG. 9, the objective lens is driven by the R_FOD signal and the relay lens is driven by the S_FOD signal as shown in FIG.
　またトラッキング制御に関してはまず、図９に示すようにＲＬ＿ＴＤＥＬ信号がＬｏｗであることから、図１０に示すようにリレーレンズのトラッキング駆動は行われない。またＯＬ＿ＴＳＥＬ信号がＬｏｗでＳ＿ＴＯＮ信号がＨｉｇｈであることから、図１０に示すように対物レンズのトラッキング駆動はＳ＿ＴＲＤ信号によって行われる。即ち、図８に示すように対物レンズ駆動サーボ層トラッキング制御が行われる。 Regarding tracking control, first, since the RL_TDEL signal is Low as shown in FIG. 9, the tracking driving of the relay lens is not performed as shown in FIG. Since the OL_TSEL signal is Low and the S_TON signal is High, the objective lens is driven for tracking by the S_TRD signal as shown in FIG. That is, objective lens drive servo layer tracking control is performed as shown in FIG.
　ステップＳ７０３において状態４から状態１に切り替えることは、例えばまずＳ＿ＴＯＮ信号及びＲ＿ＴＯＮ信号をＬｏｗレベルにしてＳ＿ＴＲＤ信号及びＴ＿ＴＲＤ信号を基準電位Ｖｒｅｆとし、その後にＯＬ＿ＴＳＥＬ信号をＨｉｇｈレベルからＬｏｗレベルに切り替えて回路を変更し、その後にＳ＿ＴＲＤ信号をＨｉｇｈにしてサーボ層に対しトラック引き込みを行うことで実現できる。このように本実施例のトラッキング制御系の回路変更は、トラッキング制御のオン・オフを指示する信号であるＳ＿ＴＯＮ信号及びＲ＿ＴＯＮ信号を共にＬｏｗレベルにした後、回路を切り替える信号であるＯＬ＿ＴＳＥＬ及びＲＬ＿ＴＳＥＬ及びＲ＿ＴＥＳＥＬを必要に応じて切り替え、その後にＳ＿ＴＯＮ信号及びＲ＿ＴＯＮ信号を必要に応じてＨｉｇｈレベルに変更して所望の層に対してトラック引き込みを行うことで実現できる。 In step S703, the state 4 is switched to the state 1 by, for example, first setting the S_TON signal and the R_TON signal to the low level, setting the S_TRD signal and the T_TRD signal to the reference potential Vref, and then switching the OL_TSEL signal from the high level to the low level. Then, the S_TRD signal is set to High and track pull-in is performed with respect to the servo layer. As described above, the circuit change of the tracking control system according to the present embodiment is performed by setting both the S_TON signal and the R_TON signal, which are signals for instructing on / off of the tracking control, to the low level, and then the signals OL_TSEL and RL_TSEL which are the circuit switching signals. This can be realized by switching R_TESEL as necessary, and then changing the S_TON signal and the R_TON signal to High level as necessary to perform track pull-in to a desired layer.
　ステップＳ７０３の後、光ディスク装置１０１はシステム制御回路１５０１からスライダ制御回路１５２１に対して指令を出し、光ピックアップ１０３が所定の半径に来るように、スライダモータ１１２を駆動させる（ステップＳ７０４）。本実施例においては、所定の半径とは、光ディスク１０２の最内周の半径であるとする。 After step S703, the optical disc apparatus 101 issues a command from the system control circuit 1501 to the slider control circuit 1521 to drive the slider motor 112 so that the optical pickup 103 comes to a predetermined radius (step S704). In the present embodiment, the predetermined radius is assumed to be the innermost radius of the optical disc 102.
　続いて光ディスク装置１０１は、ホスト１１４から記録を指示された情報の一部を記録する。この時、ディスクの２回転以上は記録を行う（ステップＳ７０５）。この動作を、以下、初回記録と呼ぶ。 Subsequently, the optical disc apparatus 101 records a part of information instructed to be recorded by the host 114. At this time, recording is performed for two or more rotations of the disc (step S705). This operation is hereinafter referred to as initial recording.
　ステップＳ７０５にてディスクの２回転以上の情報を記録した後、光ディスク装置１０１は初回記録を停止する（ステップＳ７０６）。 After recording information of two or more revolutions of the disc in step S705, the optical disc apparatus 101 stops the initial recording (step S706).
　ステップＳ７０６の後、光ディスク装置１０１は対物レンズ駆動サーボ層トラッキング制御を終了する（ステップＳ７０７）。これはＳ＿ＴＯＮ信号をＬｏｗレベルにすることで実現できる。ステップＳ７０７の後は、ステップＳ７０２に戻る。 After step S706, the optical disc apparatus 101 ends the objective lens drive servo layer tracking control (step S707). This can be realized by setting the S_TON signal to a low level. After step S707, the process returns to step S702.
　現在挿入されている光ディスクにとって、本記録処理による記録が初回記録でなかった場合（ステップＳ７０２でＮｏの場合）、ディスク装置１０１はシステム制御回路１５０１からスライダ制御回路１５２１に対して指令を出し、光ピックアップ１０３が所定の半径に来るように、スライダモータ１１２を駆動させる（ステップＳ７０８）。ここで所定の半径とは、ステップＳ７０４と共通の半径であり、光ディスク１０２の最内周の半径である。 If the recording by this recording process is not the first recording for the currently inserted optical disk (No in step S702), the disk device 101 issues a command from the system control circuit 1501 to the slider control circuit 1521 to The slider motor 112 is driven so that the pickup 103 comes to a predetermined radius (step S708). Here, the predetermined radius is a radius common to step S704 and is a radius of the innermost circumference of the optical disc 102.
　なお、ステップＳ７０２でＮｏとなる場合は、ホスト１１４から情報の記録を指示された時点で挿入されている光ディスクが過去に情報が記録されたことがあった場合か、もしくはホスト１１４から情報の記録を指示された時点で挿入されている光ディスクが過去に一度も情報が記録されたことがなく、ホスト１１４から情報の記録を指示された後にステップＳ７０３以降の初回記録を経てステップＳ７０２に戻った場合である。すなわち、ステップＳ７０８以降の処理は、光ディスク１０２の最内周の半径位置が２トラック以上に渡って記録された状態で行われることになる。 Note that if No in step S702, information has been recorded in the past on the optical disk inserted at the time when the recording of information is instructed from the host 114, or the recording of information from the host 114 has occurred. When no information has been recorded on the optical disc inserted at the time of instructing the recording, and the recording of information is instructed from the host 114, and after returning to step S702 after the initial recording from step S703. It is. That is, the processing after step S708 is performed in a state where the innermost radial position of the optical disc 102 is recorded over two or more tracks.
　ステップＳ７０８の後、光ディスク装置１０１はステップＳ７０９からステップＳ７１６までのトラックピッチ調整を行う。トラックピッチ調整を行う領域は初回記録にて記録された領域であり、本実施例における初回記録はトラックピッチ調整を行うための記録部を作成するための処理と言うこともできる。ステップＳ７０８の後、記録層ＳｕｂＳｐｏｔトラッキング制御を開始する（ステップＳ７０９）。この処理においては、図８乃至図１０における動作状態を、状態１から状態２に切り替えることに相当する。 After step S708, the optical disc apparatus 101 performs track pitch adjustment from step S709 to step S716. The area where the track pitch adjustment is performed is an area recorded by the initial recording, and the initial recording in this embodiment can be said to be a process for creating a recording unit for adjusting the track pitch. After step S708, recording layer SubSpot tracking control is started (step S709). This process corresponds to switching the operation state in FIGS. 8 to 10 from state 1 to state 2.
　続いて光ディスク装置１０１は、同じトラックを追従し続けるように、光ディスク１０１の回転に同期して１トラックジャンプを行う（ステップＳ７１０）。 Subsequently, the optical disc apparatus 101 performs a one-track jump in synchronization with the rotation of the optical disc 101 so as to keep following the same track (step S710).
　ステップＳ７１０の後、光ディスク装置１０１は記録層ＭａｉｎＴＥ信号モニタ回路１５２３でモニタしたＲ＿ＭａｉｎＴＥ信号の値を記憶する（ステップＳ７１１）。続いて記録層トラックピッチ調整電圧生成回路１５１４に指示してＲ＿ＴｐＡｄｊ信号の電圧Ｖ＿ＴｐＡｄｊを変更する（ステップＳ７１２）。 After step S710, the optical disc apparatus 101 stores the value of the R_MainTE signal monitored by the recording layer MainTE signal monitor circuit 1523 (step S711). Subsequently, the recording layer track pitch adjustment voltage generation circuit 1514 is instructed to change the voltage V_TpAdj of the R_TpAdj signal (step S712).
　ステップＳ７１２の後、記録層ＭａｉｎＴＥ信号モニタ回路１５２３でモニタしたＲ＿ＭａｉｎＴＥ信号の情報から、Ｒ＿ＭａｉｎＴＥ信号のレベルが基準電位Ｖｒｅｆを跨いで変化したかどうかを確認する。 After step S712, it is confirmed from the information of the R_MainTE signal monitored by the recording layer MainTE signal monitor circuit 1523 whether the level of the R_MainTE signal has changed across the reference potential Vref.
　Ｒ＿ＭａｉｎＴＥ信号のレベルが基準電位Ｖｒｅｆを跨いで変化していない場合（ステップＳ７１３でＮｏの場合）、ステップＳ７１１に戻る。即ち、Ｒ＿ＭａｉｎＴＥ信号のレベルが基準電位Ｖｒｅｆを跨いで変化するまで、ステップＳ７１１及びステップＳ７１２を繰り返す動作となる。 If the level of the R_MainTE signal does not change across the reference potential Vref (No in step S713), the process returns to step S711. That is, the operation of repeating steps S711 and S712 is repeated until the level of the R_MainTE signal changes across the reference potential Vref.
　Ｒ＿ＭａｉｎＴＥ信号のレベルが基準電位Ｖｒｅｆを跨いで変化した場合（ステップＳ７１３でＹｅｓの場合）、ステップＳ７１０で開始した光ディスク１０１の回転に同期して１トラックジャンプ動作を停止する（ステップＳ７１４）。 When the level of the R_MainTE signal changes across the reference potential Vref (Yes in step S713), the one-track jump operation is stopped in synchronization with the rotation of the optical disc 101 started in step S710 (step S714).
　続いて光ディスク装置１０１は、ステップＳ７１２にて設定した電圧Ｖ＿ＴｐＡｄｊと、その時に記憶されたＲ＿ＭａｉｎＴＥ信号の値から、記録層トラックピッチ調整電圧生成回路１５１４が出力する電圧Ｖ＿ＴｐＡｄｊの最適値を算出する（ステップＳ７１５）。 Subsequently, the optical disc apparatus 101 calculates the optimum value of the voltage V_TpAdj output from the recording layer track pitch adjustment voltage generation circuit 1514 from the voltage V_TpAdj set in Step S712 and the value of the R_MainTE signal stored at that time (Step S712). S715).
　ステップＳ７１５の後、光ディスク装置１０１は記録層トラックピッチ調整電圧生成回路１５１４に指示して、Ｒ＿ＴｐＡｄｊ信号の電圧Ｖ＿ＴｐＡｄｊを最適値に変更する（ステップＳ７１６）。 After step S715, the optical disc apparatus 101 instructs the recording layer track pitch adjustment voltage generation circuit 1514 to change the voltage V_TpAdj of the R_TpAdj signal to an optimum value (step S716).
　ステップＳ７１６にてトラックピッチ調整が完了した後、光ディスク装置１０１はリレーレンズ駆動サーボ層トラッキング制御を開始する（ステップＳ７１７）。この処理においては、図８乃至図１０における動作状態を、状態２から状態３に切り替えることに相当する。 After the track pitch adjustment is completed in step S716, the optical disc apparatus 101 starts relay lens driving servo layer tracking control (step S717). This process corresponds to switching the operation state in FIGS. 8 to 10 from state 2 to state 3.
　ステップＳ７１７にてリレーレンズ駆動サーボ層トラッキング制御を開始した後、情報の記録を行い、ホスト１１４から記録を指示された情報を全て記録する（ステップＳ７１８）。ステップＳ７０５の初回記録を実施していた場合には、記録された続きから情報の記録を再開するものとする。ステップＳ７１８にて情報の記録を終えると、記録処理を終了する（ステップＳ７１９）。 After starting relay lens drive servo layer tracking control in step S717, information is recorded, and all information instructed to be recorded by the host 114 is recorded (step S718). If the initial recording in step S705 has been performed, the recording of information is resumed from the recorded continuation. When the information recording is finished in step S718, the recording process is finished (step S719).
　ステップＳ７１５におけるＶ＿ＴｐＡｄｊの最適値の算出方法について説明する前にまず、本実施例による効果について説明する。その後に、その目的を達成するためのＶ＿ＴｐＡｄｊの最適値の算出方法について説明する。 Before describing the method of calculating the optimum value of V_TpAdj in step S715, first, the effect of this embodiment will be described. Then, the calculation method of the optimal value of V_TpAdj for achieving the purpose will be described.
　本実施例の効果は、記録層ＳｕｂＳｐｏｔトラッキング制御を行う場合の課題を解決できる点にある。そのため、はじめに記録層ＳｕｂＳｐｏｔトラッキング制御を行うことの利点について説明する。続いて、記録層ＳｕｂＳｐｏｔトラッキング制御を行う場合の課題を説明し、最後に本実施例の効果を説明する。 The effect of the present embodiment is that the problem in the case of performing the recording layer SubSpot tracking control can be solved. Therefore, first, the advantage of performing the recording layer SubSpot tracking control will be described. Subsequently, a problem when performing the recording layer SubSpot tracking control will be described, and finally, the effect of the present embodiment will be described.
　まず記録層ＳｕｂＳｐｏｔトラッキング制御を行う利点について、図１１を用いて説明する。図１１は記録層ＳｕｂＳｐｏｔトラッキング制御を行わずに記録層に対して情報の記録を行う場合の光ディスク１０２とレーザスポットの位置関係を示している。 First, the advantage of performing the recording layer SubSpot tracking control will be described with reference to FIG. FIG. 11 shows the positional relationship between the optical disc 102 and the laser spot when information is recorded on the recording layer without performing the recording layer SubSpot tracking control.
　図１１（ａ）は光ディスク１０２が対物レンズに対して傾いていない理想状態を示している。記録層ＳｕｂＳｐｏｔトラッキング制御を行わない場合、トラッキング制御は本明細書でサーボ層トラッキング制御と称している方式で行う。本実施例と異なり記録層に生じるレーザスポットは一つであり、Ｒ＿ＬＳで表記する。 FIG. 11A shows an ideal state where the optical disk 102 is not inclined with respect to the objective lens. When the recording layer SubSpot tracking control is not performed, the tracking control is performed by a method referred to as servo layer tracking control in this specification. Unlike this embodiment, there is one laser spot generated in the recording layer, which is represented by R_LS.
　即ち、サーボ層に照射されるレーザ光Ｓ＿ＬＢによってサーボ層にサーボ層レーザスポットＳ＿ＬＳを生成し、これを用いてトラッキング制御を行う。一方で、記録層に照射されるレーザ光Ｒ＿ＬＢによって記録層に記録層レーザスポットＲ＿ＬＳを生成し、これを用いて情報の記録を行う。光ディスク１０２が対物レンズに対して傾いていない場合には、サーボ層レーザスポットＳ＿ＬＳと記録層レーザスポットＲ＿ＬＳはディスクに垂直な軸上に位置する。 That is, the servo layer laser spot S_LS is generated on the servo layer by the laser beam S_LB irradiated to the servo layer, and tracking control is performed using this. On the other hand, the recording layer laser spot R_LS is generated in the recording layer by the laser beam R_LB irradiated to the recording layer, and information is recorded using this. When the optical disk 102 is not inclined with respect to the objective lens, the servo layer laser spot S_LS and the recording layer laser spot R_LS are located on an axis perpendicular to the disk.
　一方で、図１１（ｂ）は対物レンズに対して光ディスク１０２が傾いた状態を示しており、Ａは光ディスク１０２が対物レンズに対して傾いていない場合の記録層レーザスポットＲ＿ＬＳの位置を示す。図１１（ｂ）から明らかなように、対物レンズに対して光ディスク１０２が傾いた状態の場合の記録層レーザスポットＲ＿ＬＳは、Ａと一致しない。 On the other hand, FIG. 11B shows a state where the optical disc 102 is tilted with respect to the objective lens, and A shows the position of the recording layer laser spot R_LS when the optical disc 102 is not tilted with respect to the objective lens. As is clear from FIG. 11B, the recording layer laser spot R_LS when the optical disk 102 is tilted with respect to the objective lens does not coincide with A.
　このことから、記録層ＳｕｂＳｐｏｔトラッキング制御を行わずに記録層に対して情報の記録を行う場合には、光ディスク１０２と対物レンズの相対的な傾きが変化すると記録済みデータを上書きしてしまう等の課題がある。この課題が解決できない場合、途中まで記録したグルーブレスディスクに対する情報の追加記録を行うことができない。 Therefore, when information is recorded on the recording layer without performing the recording layer SubSpot tracking control, the recorded data is overwritten when the relative inclination of the optical disc 102 and the objective lens changes. There are challenges. If this problem cannot be solved, information cannot be additionally recorded on the grooveless disc recorded halfway.
　光ディスク１０２と対物レンズの相対的な傾きが変化する要因としては、温度や湿度による光ディスク自体の反りの変化や、チャッキングによる光ディスク装置１０１と光ディスク１０２の相対的な位置関係の変化などがある。 Factors that change the relative inclination of the optical disk 102 and the objective lens include a change in warpage of the optical disk itself due to temperature and humidity, and a change in the relative positional relationship between the optical disk device 101 and the optical disk 102 due to chucking.
　これに対し記録層ＳｕｂＳｐｏｔトラッキング制御では、図５で説明したように隣接記録層トラックに記録層サブスポットＲ＿ＳｕｂＬＳを照射してトラッキング制御を行い、そこから半径方向にＴｐだけ離れた位置に記録層メインスポットＲ＿ＭａｉｎＬＳの位置が制御される。そのため、記録層ＳｕｂＳｐｏｔトラッキング制御を用いることで、光ディスク１０２と対物レンズの相対的な傾きが変化すると記録済みデータを上書きしてしまう課題を解決できる。即ち記録層ＳｕｂＳｐｏｔトラッキング制御を用いることで、グルーブレスディスクに対する情報の追加記録が可能になる。 On the other hand, in the recording layer SubSpot tracking control, as described in FIG. 5, the adjacent recording layer track is irradiated with the recording layer sub-spot R_SubLS to perform tracking control, and the recording layer main is located at a position separated by Tp in the radial direction. The position of the spot R_MainLS is controlled. Therefore, by using the recording layer SubSpot tracking control, it is possible to solve the problem of overwriting recorded data when the relative inclination of the optical disk 102 and the objective lens changes. That is, by using the recording layer SubSpot tracking control, additional information can be recorded on the grooveless disc.
　以上で説明したように、記録層ＳｕｂＳｐｏｔトラッキング制御はグルーブレスディスクに対する情報の追加記録を実現できる制御方法である。しかしながら、記録層ＳｕｂＳｐｏｔトラッキング制御を実現する上では別の課題が存在する。次にこの課題について説明する。 As described above, the recording layer SubSpot tracking control is a control method that can realize additional recording of information on the grooveless disc. However, another problem exists in realizing the recording layer SubSpot tracking control. Next, this problem will be described.
　続いて、記録層ＳｕｂＳｐｏｔトラッキング制御を行う場合の課題を説明する。図１２は、記録層ＳｕｂＳｐｏｔトラッキング制御を行う場合の記録層上のレーザスポットを示す模式図である。点線は記録層に形成されるトラックの位置を示し、記録層メインスポットＲ＿ＭａｉｎＬＳから半径方向にサーボ層のトラックピッチＴｐだけ離れた位置に、記録層サブスポットＲ＿ＳｕｂＬＳが存在する関係にある。記録層メインスポットＲ＿ＭａｉｎＬＳの中心と記録層サブスポットＲ＿ＳｕｂＬＳの中心との距離をｄ、記録層メインスポットＲ＿ＭａｉｎＬＳの中心と記録層サブスポットＲ＿ＳｕｂＬＳの中心を結ぶ線分と接線方向とのなす角をθで示している。 Subsequently, a problem in the case where the recording layer SubSpot tracking control is performed will be described. FIG. 12 is a schematic diagram showing a laser spot on the recording layer when the recording layer SubSpot tracking control is performed. The dotted line indicates the position of the track formed in the recording layer, and the recording layer sub-spot R_SubLS exists at a position separated from the recording layer main spot R_MainLS by the track pitch Tp of the servo layer in the radial direction. The distance between the center of the recording layer main spot R_MainLS and the center of the recording layer sub-spot R_SubLS is d, and the angle between the line segment connecting the center of the recording layer main spot R_MainLS and the center of the recording layer sub-spot R_SubLS and the tangential direction is θ. Show.
　距離ｄや角θの設計中心値は、サーボ層のトラックピッチＴｐを用いて
Ｔｐ＝ｄ＊ｓｉｎθ
の関係式を満たすように選定される。しかしながら実際の光ディスク装置においては、距離ｄや角θは、部品の製造ばらつきや組み立てばらつき等の理由によって、ばらつきが生じる。ばらつきが生じた場合、記録層に形成される記録層トラックのトラックピッチは、設計中心であるＴｐからずれてしまう。 The design center value of the distance d and the angle θ is Tp = d * sin θ using the track pitch Tp of the servo layer.
Is selected so as to satisfy the relational expression. However, in an actual optical disc apparatus, the distance d and the angle θ vary due to reasons such as component manufacturing variations and assembly variations. When the variation occurs, the track pitch of the recording layer track formed in the recording layer deviates from Tp which is the design center.
　また光ディスク自体に反りがある場合や、光ディスク装置１０１に対して光ディスク１０２が傾いて装着された場合、光ディスク１０２と対物レンズの相対的な傾きが平行でない場合には、図１２の紙面が傾くことになり、傾いた紙面に照射される２つのレーザスポットのトラック方向の距離は、Ｔｐからずれてしまう。 In addition, when the optical disk itself is warped, when the optical disk 102 is mounted with an inclination relative to the optical disk apparatus 101, or when the relative inclination of the optical disk 102 and the objective lens is not parallel, the paper surface of FIG. Thus, the distance in the track direction between the two laser spots irradiated on the inclined paper surface deviates from Tp.
　記録層トラックのトラックピッチがＴｐからずれてしまうと、シークする際の計算に誤差が生じ、シーク性能が劣化する。また、トラックピッチが小さくなると、隣接マークの影響によって再生性能が劣化してしまう。更に記録層トラックのトラックピッチが変化すると１層あたりの記録容量も変化してしまうため、光ディスク１０２のデータ容量を規定できなくなる。 If the track pitch of the recording layer track deviates from Tp, an error occurs in the calculation when seeking, and seek performance deteriorates. Further, when the track pitch is reduced, the reproduction performance is deteriorated due to the influence of adjacent marks. Further, when the track pitch of the recording layer track changes, the recording capacity per layer also changes, and the data capacity of the optical disc 102 cannot be defined.
　即ち、記録層ＳｕｂＳｐｏｔトラッキング制御を行う場合の課題には、部品の製造ばらつきや組み立てばらつき等の理由によって、記録層に形成される記録層トラックのトラックピッチがＴｐからずれてしまうことである。 That is, a problem in performing the recording layer SubSpot tracking control is that the track pitch of the recording layer track formed on the recording layer is deviated from Tp due to manufacturing variations or assembly variations of parts.
　次に本実施例の効果について、図１３を用いて説明する。図１３は、記録層ＳｕｂＳｐｏｔトラッキング制御を行う場合の記録層上のレーザスポットを示す模式図である。ここは部品の製造ばらつきや組み立てばらつき等の理由によって、記録層に形成される記録層トラックのトラックピッチがＴｐからずれた場合を示しており、トラックピッチがΔＴｐだけ短くなってしまった場合を示している。また内周から外周に向かって情報を記録していく場合を示しているものとする。即ち、図の左方向が内周方向に相当する。 Next, the effect of this embodiment will be described with reference to FIG. FIG. 13 is a schematic diagram showing a laser spot on the recording layer when the recording layer SubSpot tracking control is performed. This shows a case where the track pitch of the recording layer track formed on the recording layer is deviated from Tp due to parts manufacturing variation or assembly variation, and shows a case where the track pitch is shortened by ΔTp. ing. It is assumed that information is recorded from the inner periphery toward the outer periphery. That is, the left direction in the figure corresponds to the inner circumferential direction.
　図１３（ａ）は本実施例を用いずに記録層ＳｕｂＳｐｏｔトラッキング制御を行った場合を示しており、記録層トラックのトラックピッチはＴｐ－ΔＴｐとなる。これに対し本発明では図１３（ｂ）に示すように、記録層サブスポットＲ＿ＳｕｂＬＳの制御位置を変更する。即ち記録層サブスポットＲ＿ＳｕｂＬＳが、隣接トラックを追従するように制御するのではなく、隣接トラックからΔＴｐだけ外周側の位置に制御する。これにより、記録層トラックのトラックピッチはＴｐとなる。 FIG. 13A shows a case where the recording layer SubSpot tracking control is performed without using this embodiment, and the track pitch of the recording layer track is Tp−ΔTp. In contrast, in the present invention, as shown in FIG. 13B, the control position of the recording layer sub-spot R_SubLS is changed. That is, the recording layer sub-spot R_SubLS is not controlled to follow the adjacent track, but is controlled to a position on the outer peripheral side by ΔTp from the adjacent track. Thereby, the track pitch of the recording layer track becomes Tp.
　このような制御位置の変更は、トラッキングエラー信号にオフセットを印加することで実現できる。本実施例においては、記録層トラックピッチ調整電圧生成回路１５１４がオフセット出力部として機能する。また、記録層トラックピッチ調整電圧生成回路１５１４が出力する電圧Ｖ＿ＴｐＡｄｊが、上記オフセットに相当する。 Such a change in the control position can be realized by applying an offset to the tracking error signal. In this embodiment, the recording layer track pitch adjustment voltage generation circuit 1514 functions as an offset output unit. The voltage V_TpAdj output from the recording layer track pitch adjustment voltage generation circuit 1514 corresponds to the offset.
　即ちステップＳ７０９からステップＳ７１６までのトラックピッチ調整では、図１３（ａ）のようにトラックピッチがずれた状態から、記録層トラックのトラックピッチがＴｐとなる図１３（ｂ）の状態にするための電圧Ｖ＿ＴｐＡｄｊを求める調整である。本実施例のトラックピッチ調整では電圧Ｖ＿ＴｐＡｄｊを変更した際のＲ＿ＭａｉｎＴＥ信号の値をモニタする。この意味について、図１４、図１５を用いて説明する。 That is, in the track pitch adjustment from step S709 to step S716, the track pitch is shifted from the state as shown in FIG. 13A to the state shown in FIG. 13B where the track pitch of the recording layer track becomes Tp. This is adjustment for obtaining the voltage V_TpAdj. In the track pitch adjustment of this embodiment, the value of the R_MainTE signal when the voltage V_TpAdj is changed is monitored. This meaning will be described with reference to FIGS.
　図１４は、電圧Ｖ＿ＴｐＡｄｊを変更した際の記録層上のレーザスポットを示す模式図である。図１４（ａ）は初期状態であり、図１３と同様に記録層トラックのトラックピッチがＴｐ－ΔＴｐの状態を初期状態としている。これに対し図１４（ｂ）は電圧Ｖ＿ＴｐＡｄｊが最適値の状態であり、トラックピッチがＴｐとなる状態である。最適なＶ＿ＴｐＡｄｊの最適値を、Ｖ＿ＢｅｓｔＴｐＡｄｊとする。また図１４（ｃ）は、電圧Ｖ＿ＴｐＡｄｊの値を２×Ｖ＿ＢｅｓｔＴｐＡｄｊとした場合を示している。 FIG. 14 is a schematic diagram showing a laser spot on the recording layer when the voltage V_TpAdj is changed. FIG. 14A shows the initial state, and the state where the track pitch of the recording layer track is Tp−ΔTp is the initial state as in FIG. On the other hand, FIG. 14B shows a state in which the voltage V_TpAdj is an optimal value and the track pitch is Tp. The optimum value of the optimum V_TpAdj is V_BestTpAdj. FIG. 14C shows a case where the value of the voltage V_TpAdj is 2 × V_BestTpAdj.
　図１４（ａ）、（ｂ）からわかるように、電圧Ｖ＿ＴｐＡｄｊとして最適値Ｖ＿ＢｅｓｔＴｐＡｄｊを印加することで、記録層サブスポットＲ＿ＳｕｂＬＳは外周側にΔＴｐだけ移動する。このことから、図１４（ｃ）は、図１４（ａ）の初期状態から記録層サブスポットＲ＿ＳｕｂＬＳが外周側に２×ΔＴｐだけ移動した状態である。そのため、図１４（ｂ）の最適状態との比較では、記録層サブスポットＲ＿ＳｕｂＬＳが外周側にΔＴｐだけ移動した関係にある。この結果、記録層サブスポットＲ＿ＳｕｂＬＳの半径方向の位置に着目すれば、（ａ）と（ｃ）は最適状態（ｂ）を中心に対称な関係にある。 14A and 14B, when the optimum value V_BestTpAdj is applied as the voltage V_TpAdj, the recording layer sub-spot R_SubLS moves to the outer peripheral side by ΔTp. Accordingly, FIG. 14C shows a state in which the recording layer sub-spot R_SubLS has moved by 2 × ΔTp from the initial state of FIG. Therefore, in the comparison with the optimum state in FIG. 14B, the recording layer sub-spot R_SubLS has a relationship of moving by ΔTp to the outer peripheral side. As a result, when focusing on the radial position of the recording layer sub-spot R_SubLS, (a) and (c) are in a symmetrical relationship with the optimum state (b) as the center.
　この図１４（ａ）、（ｂ）、（ｃ）の場合に、Ｒ＿ＭａｉｎＴＥ信号の値がどうなるかについて、図１５を用いて説明する。 In the case of FIGS. 14A, 14B, and 14C, what happens to the value of the R_MainTE signal will be described with reference to FIG.
　図１５は、記録層メインスポットＲ＿ＭａｉｎＬＳがトラックを横切った場合のＲ＿ＭａｉｎＴＥ信号の波形を示している。図１５の（ａ）、（ｂ）、（ｃ）はそれぞれ、図１４の（ａ）、（ｂ）、（ｃ）と対応する。Ｒ＿ＭａｉｎＴＥ信号をＤＰＤ（Ｄｉｆｆｅｒｅｎｔｉａｌ　Ｐｈａｓｅ．　Ｄｅｔｅｃｔｉｏｎ）法で生成している場合、図１５に示すようにＲ＿ＭａｉｎＴＥ信号は三角波となる。図中、傾きが正である領域Ａは負期間領域と呼ばれ、この範囲はトラッキング制御が制御可能な範囲である。Ｂで示す傾きが負の領域では、トラッキング制御ができない領域である。 FIG. 15 shows the waveform of the R_MainTE signal when the recording layer main spot R_MainLS crosses the track. (A), (b), and (c) in FIG. 15 correspond to (a), (b), and (c) in FIG. 14, respectively. When the R_MainTE signal is generated by the DPD (Differential Phase. Detection) method, the R_MainTE signal becomes a triangular wave as shown in FIG. In the figure, a region A having a positive slope is called a negative period region, and this range is a range in which tracking control can be controlled. A region where the slope indicated by B is negative is a region where tracking control cannot be performed.
　記録層メインスポットＲ＿ＭａｉｎＬＳが隣接トラック上に照射される時、Ｒ＿ＭａｉｎＴＥ信号は基準電位Ｖｒｅｆの値を取る。そのため、図１５の（ｂ）において、Ｒ＿ＭａｉｎＴＥ信号はＶｒｅｆとなる。また、（ａ）と（ｃ）は、図１５に示すように最適状態（ｂ）を中心に対称な関係になる。これは、Ｒ＿ＭａｉｎＴＥ信号が記録層メインスポットＲ＿ＭａｉｎＬＳと隣接トラックの半径方向の距離を示す信号であるためである。 When the recording layer main spot R_MainLS is irradiated onto the adjacent track, the R_MainTE signal takes the value of the reference potential Vref. Therefore, in FIG. 15B, the R_MainTE signal is Vref. Further, (a) and (c) have a symmetrical relationship with the optimum state (b) as the center as shown in FIG. This is because the R_MainTE signal is a signal indicating the radial distance between the recording layer main spot R_MainLS and the adjacent track.
　以上で説明した、記録層トラックピッチ調整電圧生成回路１５１４が出力する電圧Ｖ＿ＴｐＡｄｊとそのときのＲ＿ＭａｉｎＴＥ信号の値の関係を元に、本実施例のトラックピッチ調整（ステップＳ７０９からステップＳ７１６）をどのように行うかについて説明する。 Based on the relationship between the voltage V_TpAdj output from the recording layer track pitch adjustment voltage generation circuit 1514 described above and the value of the R_MainTE signal at that time, how is the track pitch adjustment (steps S709 to S716) of this embodiment performed? I will explain what to do.
　図１６に、本実施例のトラックピッチ調整を行っている最中の各部の信号と、電圧Ｖ＿ＴｐＡｄｊの最適値を算出する方法を示す。 FIG. 16 shows a signal for each part during the track pitch adjustment of this embodiment and a method for calculating the optimum value of the voltage V_TpAdj.
　図１６（ａ）は本実施例のトラックピッチ調整を行っている最中の電圧Ｖ＿ＴｐＡｄｊの値を示し、また図１６（ｂ）はそのときに記録層ＭａｉｎＴＥ信号モニタ回路１５２３でモニタされるＲ＿ＭａｉｎＴＥ信号の値（ＤＣレベル）を示している。以下、記録層ＭａｉｎＴＥ信号モニタ回路１５２３でモニタされるＲ＿ＭａｉｎＴＥ信号の値をＭ＿ＴＥと表記する。 FIG. 16A shows the value of the voltage V_TpAdj during the track pitch adjustment of this embodiment, and FIG. 16B shows the R_MainTE signal monitored by the recording layer MainTE signal monitor circuit 1523 at that time. (DC level). Hereinafter, the value of the R_MainTE signal monitored by the recording layer MainTE signal monitor circuit 1523 is referred to as M_TE.
　ここでは、ステップＳ７１３にてＲ＿ＭａｉｎＴＥ信号のレベルが基準電位Ｖｒｅｆを跨いで変化するまでに、ステップＳ７１１のＲ＿ＭａｉｎＴＥ信号の記憶を４回行った場合を示している。計４回のうち、ｉ回目のＶ＿ＴｐＡｄｊの値をＶ＿ＴｐＡｄｊ［ｉ］、ｉ回目でモニタされるＲ＿ＭａｉｎＴＥ信号の値をＭ＿ＴＥ［ｉ］で表記している（ｉは１以上４以下の整数）。 Here, a case is shown where the R_MainTE signal is stored four times in step S711 until the level of the R_MainTE signal changes across the reference potential Vref in step S713. Of the four times in total, the value of V_TpAdj for the i-th time is represented by V_TpAdj [i], and the value of the R_MainTE signal monitored for the i-th time is represented by M_TE [i] (i is an integer from 1 to 4).
　ステップＳ７１２で変更する電圧Ｖ＿ＴｐＡｄｊの変化量は固定値であるので、電圧Ｖ＿ＴｐＡｄｊは階段状に縦軸方向に等間隔で変化する。図１５で説明したことから、記録層トラックピッチ調整電圧生成回路１５１４が出力する電圧Ｖ＿ＴｐＡｄｊを等間隔で変化させていくことは、記録層サブスポットＲ＿ＳｕｂＬＳが半径方向に等間隔で移動することに相当する。 Since the change amount of the voltage V_TpAdj that is changed in step S712 is a fixed value, the voltage V_TpAdj changes stepwise in the vertical axis direction at equal intervals. As described in FIG. 15, changing the voltage V_TpAdj output from the recording layer track pitch adjustment voltage generation circuit 1514 at equal intervals is equivalent to moving the recording layer sub-spot R_SubLS at equal intervals in the radial direction. To do.
　一方でＲ＿ＭａｉｎＴＥ信号のＤＣレベルは、記録層メインスポットＲ＿ＭａｉｎＬＳと隣接トラックとの半径方向の距離を示す信号であるので、電圧Ｖ＿ＴｐＡｄｊが図１６（ａ）のように階段状に変化するとき、Ｒ＿ＭａｉｎＴＥ信号のＤＣレベルも図１６（ｂ）に示すように階段状に変化する。 On the other hand, since the DC level of the R_MainTE signal is a signal indicating the radial distance between the recording layer main spot R_MainLS and the adjacent track, when the voltage V_TpAdj changes stepwise as shown in FIG. 16A, the R_MainTE signal The DC level also changes stepwise as shown in FIG.
　このようにして得られる、Ｖ＿ＴｐＡｄｊ［ｉ］とＭ＿ＴＥ［ｉ］を、図１６（ｃ）に示すようにＶ＿ＴｐＡｄｊとＭ＿ＴＥのグラフにプロットすると、各データは直線状に並ぶ。ここで、トラックピッチ調整において最終的に求めたい電圧Ｖ＿ＴｐＡｄｊの最適値は、記録層メインスポットＲ＿ＭａｉｎＬＳと隣接トラックが重なるようになる電圧Ｖ＿ＴｐＡｄｊの値である。そしてそれは図１４および図１５における（ｂ）の状態である。即ち、記録層ＭａｉｎＴＥ信号モニタ回路１５２３でモニタされるＲ＿ＭａｉｎＴＥ信号のＤＣレベルが、基準電位Ｖｒｅｆになるような電圧Ｖ＿ＴｐＡｄｊの値を求める。 When V_TpAdj [i] and M_TE [i] obtained in this way are plotted on a graph of V_TpAdj and M_TE as shown in FIG. 16C, each data is arranged in a straight line. Here, the optimum value of the voltage V_TpAdj to be finally obtained in the track pitch adjustment is the value of the voltage V_TpAdj that causes the recording layer main spot R_MainLS to overlap the adjacent track. And it is the state of (b) in FIG. 14 and FIG. That is, the value of the voltage V_TpAdj is obtained so that the DC level of the R_MainTE signal monitored by the recording layer MainTE signal monitor circuit 1523 becomes the reference potential Vref.
　従って、図１６（ｃ）で示す４つの計測データに対して近似直線Ｌを求め、Ｌと、Ｍ＿ＴＥ＝Ｖｒｅｆの交点を求め、そのときのＶ＿ＴｐＡｄｊの値が最適値となる。図１６（ｃ）においては、その値をＶ＿ｂｅｓｔとして示している。 Therefore, an approximate straight line L is obtained for the four pieces of measurement data shown in FIG. 16C, the intersection of L and M_TE = Vref is obtained, and the value of V_TpAdj at that time is an optimum value. In FIG. 16C, the value is shown as V_best.
　以上が、ステップＳ７１５における電圧Ｖ＿ＴｐＡｄｊの最適値の算出方法である。ステップＳ７１６では、ステップＳ７１５で算出した最適値を設定し、以降はその状態を継続する。 The above is the method for calculating the optimum value of the voltage V_TpAdj in step S715. In step S716, the optimum value calculated in step S715 is set, and the state is continued thereafter.
　記録層ＳｕｂＳｐｏｔトラッキング制御を行う場合の課題は、図１４（ａ）や図１４（ｃ）のように記録層メインスポットＲ＿ＭａｉｎＬＥと記録層サブスポットＲ＿ＳｕｂＬＳの半径方向の距離が、サーボ層のトラックピッチＴｐからずれてしまうことであった。これに対し、上述したトラックピッチ調整を行うことによって、記録層サブスポットＲ＿ＳｕｂＬＳの制御位置を最適な位置に変更し、図１４（ｂ）の状態となるようにすることができる。 The problem in performing the recording layer SubSpot tracking control is that the distance in the radial direction between the recording layer main spot R_MainLE and the recording layer sub-spot R_SubLS is the track pitch Tp of the servo layer as shown in FIGS. It was to deviate from. On the other hand, by performing the above-described track pitch adjustment, the control position of the recording layer sub-spot R_SubLS can be changed to the optimum position so that the state shown in FIG.
　図１４（ｂ）の状態にした上で記録層サブスポットトラッキング制御による情報の記録を行うことで、記録層トラックのトラックピッチをＴｐにすることができる。即ち本実施例の効果は、部品の製造ばらつきや組み立てばらつき等の理由によって、記録層メインスポットＲ＿ＭａｉｎＬＥと記録層サブスポットＲ＿ＳｕｂＬＳの半径方向の距離がサーボ層のトラックピッチＴｐからずれてしまう場合であっても、記録層トラックのトラックピッチをＴｐにすることができる点にある。これにより、シーク性能や再生性能の劣化を抑えることができる。 When information is recorded by recording layer sub-spot tracking control in the state shown in FIG. 14B, the track pitch of the recording layer track can be set to Tp. In other words, the effect of this embodiment is that the radial distance between the recording layer main spot R_MainLE and the recording layer sub-spot R_SubLS deviates from the track pitch Tp of the servo layer for reasons such as manufacturing variations and assembly variations of parts. However, the track pitch of the recording layer track can be set to Tp. Thereby, deterioration of seek performance and reproduction performance can be suppressed.
　ここで、記録層サブスポットトラッキング制御で情報の記録を行うステップＳ７１８においては、既に最適なＶ＿ＴｐＡｄｊが設定された状態である。言い換えれば、記録層サブスポットトラッキング制御による情報の記録を行うより前に、トラックピッチ調整を行う順序になっている。上述したようにトラックピッチ調整は記録層サブスポットトラッキング制御による情報の記録を行う上で必要な調整であるので、この順序である必要があることは明らかである。 Here, in step S718 in which information is recorded by the recording layer sub-spot tracking control, the optimum V_TpAdj has already been set. In other words, the track pitch adjustment is performed before the information is recorded by the recording layer sub-spot tracking control. As described above, since the track pitch adjustment is an adjustment necessary for recording information by the recording layer sub-spot tracking control, it is obvious that this order is necessary.
　また本実施例ではトラックピッチ調整中は回転に同期して１トラックジャンプを行う動作とした。内周から外周に向かって情報を記録していく場合、トラックピッチ調整中は記録層サブスポットＲ＿ＳｕｂＬＳより１トラック外周側に記録されたトラックがある必要がある。また、トラックピッチ調整はＲ＿ＭａｉｎＴＥ信号のをモニタするため、ディスク１回転をモニタし、その平均値（即ちＤＣレベル）を用いることが望ましい。以上から、回転に同期して１トラックジャンプを行いながらトラックピッチ調整を行うには、２トラック以上の記録された領域でトラックピッチ調整を行う必要がある。従って、ステップＳ７０５における初回記録においては、ディスクの２回転以上は記録を行う必要がある。 Also, in this embodiment, during the track pitch adjustment, an operation of performing one track jump in synchronization with the rotation is performed. When information is recorded from the inner circumference toward the outer circumference, there is a need for a track recorded on the outer circumference side of one track from the recording layer sub-spot R_SubLS during the track pitch adjustment. Further, since the track pitch adjustment monitors the R_MainTE signal, it is desirable to monitor one rotation of the disk and use the average value (ie, DC level). From the above, in order to adjust the track pitch while performing one track jump in synchronization with the rotation, it is necessary to adjust the track pitch in the recorded area of two or more tracks. Therefore, in the initial recording in step S705, it is necessary to perform recording for two or more rotations of the disc.
　また図１５では、記録層メインスポットＲ＿ＭａｉｎＬＳがトラックを横切った場合のＲ＿ＭａｉｎＴＥ信号の波形を示したが、Ｒ＿ＳｕｂＴＥ信号についても同様の波形になる。上述したようにトラッキング制御が制御可能な範囲は図１５においてＡで示した負帰還領域であることから、トラックピッチ調整で変更する電圧Ｖ＿ＴｐＡｄｊの値は、Ｒ＿ＳｕｂＴＥ信号に関するデトラック量が負帰還領域を出ない範囲で設定する必要がある。これは図１５の場合で説明すれば、電圧Ｖ＿ＴｐＡｄｊの絶対値が、領域Ａの両端におけるＲ＿ＳｕｂＴＥ信号の絶対値を超えない範囲で設定することに相当する。 FIG. 15 shows the waveform of the R_MainTE signal when the recording layer main spot R_MainLS crosses the track, but the R_SubTE signal has the same waveform. As described above, the controllable range of the tracking control is the negative feedback region indicated by A in FIG. 15. Therefore, the value of the voltage V_TpAdj to be changed by the track pitch adjustment is such that the detrack amount related to the R_SubTE signal is within the negative feedback region. It is necessary to set within the range that does not appear. In the case of FIG. 15, this corresponds to setting the absolute value of the voltage V_TpAdj within a range that does not exceed the absolute value of the R_SubTE signal at both ends of the region A.
　以上の説明では、トラックピッチ調整について、記録層ＭａｉｎＴＥ信号モニタ回路１５２３でモニタされるＲ＿ＭａｉｎＴＥ信号のＤＣレベルが、基準電位Ｖｒｅｆになるような電圧Ｖ＿ＴｐＡｄｊの値を調整するとした。しかし実際の回路では回路のオフセットが存在し、本実施例では説明を省略したが光ディスク装置１０１にはオフセットを除去する回路が備わっている場合がある。この場合、Ｒ＿ＭａｉｎＴＥ信号の調整目標とする電位は、除去するオフセット量の分だけ、信号処理回路１０５の基準電位Ｖｒｅｆからずれる。従って、より厳密には、記録層ＭａｉｎＴＥ信号モニタ回路１５２３でモニタされるＲ＿ＭａｉｎＴＥ信号のＤＣレベルが、所定の値になるように調整すると表現したほうが正確である。もちろん、回路オフセットを除去しない光ディスク装置や、回路オフセットが小さい場合、前記所定の値は基準電位Ｖｒｅｆと等しくなる。 In the above description, for the track pitch adjustment, the value of the voltage V_TpAdj is adjusted so that the DC level of the R_MainTE signal monitored by the recording layer MainTE signal monitor circuit 1523 becomes the reference potential Vref. However, there is a circuit offset in an actual circuit, and although the description is omitted in this embodiment, the optical disc apparatus 101 may be provided with a circuit for removing the offset. In this case, the adjustment target potential of the R_MainTE signal deviates from the reference potential Vref of the signal processing circuit 105 by the amount of offset to be removed. Therefore, more precisely, it is more accurate to express that the DC level of the R_MainTE signal monitored by the recording layer MainTE signal monitor circuit 1523 is adjusted to a predetermined value. Of course, when the optical disk apparatus does not remove the circuit offset or when the circuit offset is small, the predetermined value is equal to the reference potential Vref.
　また本実施例では、記録層メインスポットＲ＿ＭａｉｎＬＳと隣接トラックの半径方向の距離を示す信号であるＲ＿ＭａｉｎＴＥ信号をモニタしてトラックピッチ調整を行う構成とした。しかしトラックピッチ調整でモニタする信号は、記録層メインスポットＲ＿ＭａｉｎＬＳと隣接トラックの半径方向の距離に応じた挙動を示す信号であれば、別の信号を用いても良い。 In the present embodiment, the recording layer main spot R_MainLS and the R_MainTE signal, which is a signal indicating the radial distance between adjacent tracks, are monitored to adjust the track pitch. However, another signal may be used as the signal monitored by the track pitch adjustment as long as the signal exhibits a behavior corresponding to the radial distance between the recording layer main spot R_MainLS and the adjacent track.
　このような信号として例えば、再生信号を用いることができる。記録層メインスポットＲ＿ＭａｉｎＬＳが隣接トラック上に照射される時、Ｒ＿ＭａｉｎＬＳによって得られる再生信号の振幅は最大となり、記録層メインスポットＲ＿ＭａｉｎＬＳが隣接トラックから離れるほど、再生信号の振幅は低下する。即ち、光ディスク装置１０１がＲ＿ＭａｉｎＬＳによって得られる再生信号の振幅をモニタする回路を備え、振幅が最大となるような電圧Ｖ＿ＴｐＡｄｊの値を求めるトラックピッチ調整を行う構成であってもよい。 For example, a reproduction signal can be used as such a signal. When the recording layer main spot R_MainLS is irradiated onto the adjacent track, the amplitude of the reproduction signal obtained by the R_MainLS is maximized, and the amplitude of the reproduction signal decreases as the recording layer main spot R_MainLS is separated from the adjacent track. That is, the optical disc apparatus 101 may be provided with a circuit for monitoring the amplitude of the reproduction signal obtained by R_MainLS, and the track pitch adjustment for obtaining the value of the voltage V_TpAdj that maximizes the amplitude may be performed.
　以上ではトラックピッチ調整を行う際にモニタする信号として、Ｒ＿ＭａｉｎＴＥ信号とＲ＿ＭａｉｎＬＳによって得られる再生信号の２つを例に説明した。これらは、記録層メインスポットＲ＿ＭａｉｎＬＳにおいて反射した光の強度を検出するディテクタ１３１４から生成する点が共通である。即ち、記録層メインスポットＲ＿ＭａｉｎＬＳが隣接トラック上に照射されているかどうかを確認する信号は、ディテクタ１３１４の出力を用いればよい。更に言えば、ディテクタ１３１４から生成される信号であれば、上記２つ以外の信号をモニタしても構わないことは明らかである。 In the above, two signals, the R_MainTE signal and the reproduction signal obtained by R_MainLS, have been described as examples of signals to be monitored when track pitch adjustment is performed. These are common in that they are generated from a detector 1314 that detects the intensity of light reflected at the recording layer main spot R_MainLS. That is, the output of the detector 1314 may be used as a signal for confirming whether or not the recording layer main spot R_MainLS is irradiated on the adjacent track. Further, it is obvious that signals other than the above two may be monitored as long as the signals are generated from the detector 1314.
　以上の実施例によれば、記録層ＳｕｂＳｐｏｔトラッキング制御を行う場合の課題を解決でき、記録層ＳｕｂＳｐｏｔトラッキング制御を適切に行うことが可能になる。 According to the above embodiment, the problem in the case of performing the recording layer SubSpot tracking control can be solved, and the recording layer SubSpot tracking control can be appropriately performed.
　即ち、光ディスク１０２と対物レンズの相対的な傾きが変化する場合であっても記録済みデータを上書きしてしまうことを防止し、グルーブレスディスクに対する情報の追加記録を行うことが可能になる。またその際、記録層トラックのトラックピッチをサーボ層のトラックピッチＴｐと精度良く一致させることが可能になり、良好なシーク性能や良好な再生性能を達成できる。更には、光ディスク１０２のデータ容量を確実に規定できる。 That is, even when the relative tilt between the optical disk 102 and the objective lens changes, it is possible to prevent overwriting recorded data and to perform additional recording of information on the grooveless disk. At that time, the track pitch of the recording layer track can be made to coincide with the track pitch Tp of the servo layer with high accuracy, and good seek performance and good reproduction performance can be achieved. Furthermore, the data capacity of the optical disk 102 can be defined reliably.
　このように本実施例によれば、グルーブレスディスクに対して適切に追加記録を行うことができる。 Thus, according to this embodiment, additional recording can be appropriately performed on the grooveless disc.
　実施例１においては、ホスト１１４から情報の記録を指示された場合の記録処理において、光ディスク装置１０１に挿入された光ディスク１０２の記録部を用いてトラックピッチ調整を行う構成とした。これは記録層トラックのトラックピッチがＴｐからずれてしまう課題を解決するためのものであり、その課題が生じる原因は本明細書で２つを挙げている。１つは部品の製造ばらつきや組み立てばらつきであり、もう１つは光ディスク自体の反りや光ディスク１０２装着時の傾きである。 In the first embodiment, the track pitch adjustment is performed using the recording unit of the optical disc 102 inserted in the optical disc apparatus 101 in the recording process when the host 114 is instructed to record information. This is for solving the problem that the track pitch of the recording layer track deviates from Tp, and there are two causes for this problem in this specification. One is the manufacturing variation or assembly variation of the parts, and the other is the warp of the optical disc itself or the inclination when the optical disc 102 is mounted.
　このうち、支配的な要因が前者であれば、記録層トラックピッチのずれ量はピックアップに固有の値となる。本実施例はこのことに着目した実施の形態である。 Of these, if the dominant factor is the former, the recording layer track pitch deviation is a value specific to the pickup. The present embodiment is an embodiment paying attention to this.
　本実施例の光ディスク装置のブロック図は、実施例１のブロック図である図１と共通である。またサーボエラー信号生成回路１０４の構成及び信号処理回路１０５の構成についても実施例１の構成図である図２及び図３と共通である。 The block diagram of the optical disk apparatus of the present embodiment is the same as FIG. 1 which is a block diagram of the first embodiment. Further, the configuration of the servo error signal generation circuit 104 and the configuration of the signal processing circuit 105 are also the same as those in FIGS. 2 and 3 which are the configuration diagrams of the first embodiment.
　本実施例と実施例１との差異は、ホスト１１４から情報の記録を指示された場合の記録動作のフローチャートである。図１７に、ホスト１１４から情報の記録を指示された場合の本実施例の記録処理のフローチャートを示す。 The difference between the present embodiment and the first embodiment is a flowchart of the recording operation when the host 114 is instructed to record information. FIG. 17 shows a flowchart of the recording process of this embodiment when the host 114 is instructed to record information.
　ホスト１１４から情報の記録を指示されると、光ディスク装置１０１は記録処理を開始する（ステップＳ１７０１）。記録処理において光ディスク装置１０１はまず、現在挿入されている光ディスクにとって、本記録処理による記録が初回の記録であるかどうかの確認を行う（ステップＳ１７０２）。 When the recording of information is instructed from the host 114, the optical disc apparatus 101 starts the recording process (step S1701). In the recording process, the optical disk apparatus 101 first confirms whether or not the recording by this recording process is the first recording for the currently inserted optical disk (step S1702).
　現在挿入されている光ディスクにとって、本記録処理による記録が初回記録であった場合（ステップＳ１７０２でＹｅｓの場合）、光ディスク装置１０１は対物レンズ駆動サーボ層トラッキング制御を開始する（ステップＳ１７０３）。 When the recording by this recording process is the first recording for the currently inserted optical disc (Yes in step S1702), the optical disc apparatus 101 starts the objective lens drive servo layer tracking control (step S1703).
　ステップＳ１７０３の後、光ディスク装置１０１はシステム制御回路１５０１からスライダ制御回路１５２１に対して指令を出し、光ピックアップ１０３が所定の半径に来るように、スライダモータ１１２を駆動させる（ステップＳ１７０４）。本実施例においては、所定の半径とは、光ディスク１０２の最内周の半径であるとする。 After step S1703, the optical disc apparatus 101 issues a command to the slider control circuit 1521 from the system control circuit 1501, and drives the slider motor 112 so that the optical pickup 103 comes to a predetermined radius (step S1704). In the present embodiment, the predetermined radius is assumed to be the innermost radius of the optical disc 102.
　続いて光ディスク装置１０１は、ホスト１１４から記録を指示された情報の一部を記録する。この時、ディスクの１回転以上は記録を行う（ステップＳ１７０５）。この動作を、以下、初回記録と呼ぶ。 Subsequently, the optical disc apparatus 101 records a part of information instructed to be recorded by the host 114. At this time, recording is performed for one or more rotations of the disc (step S1705). This operation is hereinafter referred to as initial recording.
　ステップＳ１７０５にてディスクの１回転以上の情報を記録した後、光ディスク装置１０１は初回記録を停止する（ステップＳ１７０６）。 After recording information of one or more revolutions of the disc in step S1705, the optical disc apparatus 101 stops the initial recording (step S1706).
　ステップＳ１７０６の後、光ディスク装置１０１は対物レンズ駆動サーボ層トラッキング制御を終了する（ステップＳ１７０７）。 After step S1706, the optical disc apparatus 101 ends the objective lens drive servo layer tracking control (step S1707).
　現在挿入されている光ディスクにとって、本記録処理による記録が初回記録でなかった場合（ステップＳ１７０２でＮｏの場合）、光ディスク装置１０１は記録層トラックピッチ調整電圧生成回路１５１４に指示して、Ｒ＿ＴｐＡｄｊ信号の電圧Ｖ＿ＴｐＡｄｊを所定の値に変更する（ステップＳ１７０８）。この所定の値は、システム制御回路１５０１の内部に備えられた不揮発メモリ（図示しない）に記憶された値を用いる。 If the recording by this recording process is not the first recording for the currently inserted optical disk (No in step S1702), the optical disk apparatus 101 instructs the recording layer track pitch adjustment voltage generation circuit 1514 to output the R_TpAdj signal. The voltage V_TpAdj is changed to a predetermined value (step S1708). As this predetermined value, a value stored in a non-volatile memory (not shown) provided in the system control circuit 1501 is used.
　ステップＳ１７１６の後、光ディスク装置１０１は、記録層ＳｕｂＳｐｏｔトラッキング制御を開始し（ステップＳ１７０９）、続けてリレーレンズ駆動サーボ層トラッキング制御を開始する（ステップＳ１７１０）。 After step S1716, the optical disc apparatus 101 starts recording layer SubSpot tracking control (step S1709), and then starts relay lens drive servo layer tracking control (step S1710).
　ステップＳ１７１７にてリレーレンズ駆動サーボ層トラッキング制御を開始した後、情報の記録を行い、ホスト１１４から記録を指示された情報を全て記録する（ステップＳ１７１１）。ステップＳ１７０５の初回記録を実施していた場合には、記録された続きから情報の記録を再開するものとする。ステップＳ１７１１にて情報の記録を終えると、記録処理を終了する（ステップＳ１７１２）。 After starting the relay lens drive servo layer tracking control in step S1717, information is recorded, and all information instructed to be recorded by the host 114 is recorded (step S1711). If the initial recording in step S1705 has been performed, the recording of information is resumed from the recorded continuation. When the information recording is finished in step S1711, the recording process is finished (step S1712).
　本実施例の効果について説明する。前述したように、本実施例は部品の製造ばらつきや組み立てばらつきが支配的な要因となって記録層トラックのトラックピッチがＴｐからずれてしまう課題が引き起こされる場合を想定している。 The effect of this embodiment will be described. As described above, the present embodiment assumes a case in which the problem that the track pitch of the recording layer track deviates from Tp is caused by the manufacturing variation and assembly variation of components.
　ここで言及している部品ばらつきや組み立てばらつきは、ピックアップ１０３を構成する部品に関するものであるためピックアップ１０３に固有の値となる。そのため、実施例１のように記録動作の度にトラックピッチ調整を行う必要はなく、記録層サブスポットトラッキング制御による情報の記録を行うより前に、装置固有の値を設定すればよい。 The component variation and the assembly variation referred to here are related to the components constituting the pickup 103, and are values specific to the pickup 103. Therefore, it is not necessary to adjust the track pitch every time the recording operation is performed as in the first embodiment, and a value unique to the apparatus may be set before recording information by the recording layer sub-spot tracking control.
　これを実現するため本実施例では、光ディスク装置１０１を製造時に記録層上に生じる２つのレーザスポットＲ＿ＭａｉｎＬＳ、Ｒ＿ＳｕｂＬＳの半径方向の距離を調査し、その調査結果をシステム制御回路１５０１の内部に備えられた不揮発メモリに記憶する。そして記録層サブスポットトラッキング制御による情報の記録を行うより前に、その値を読み出して、記録層トラックピッチ調整電圧生成回路１５１４の電圧Ｖ＿ＴｐＡｄｊを最適な値に設定する。 In order to realize this, in this embodiment, the distance between the two laser spots R_MainLS and R_SubLS generated on the recording layer at the time of manufacturing the optical disc apparatus 101 is investigated, and the investigation result is provided in the system control circuit 1501. Store in non-volatile memory. Before the information is recorded by the recording layer sub-spot tracking control, the value is read and the voltage V_TpAdj of the recording layer track pitch adjustment voltage generation circuit 1514 is set to an optimum value.
　以上の動作により、部品の製造ばらつきや組み立てばらつきが支配的な要因である場合に、実施例１と同等の効果を達成できる。即ち、図１４（ａ）や図１４（ｃ）のように記録層メインスポットＲ＿ＭａｉｎＬＥと記録層サブスポットＲ＿ＳｕｂＬＳの半径方向の距離が、サーボ層のトラックピッチＴｐからずれてしまう場合であっても、上述したトラックピッチ調整を行うことによって、記録層サブスポットＲ＿ＳｕｂＬＳの制御位置を最適な位置に変更し、図１４（ｂ）の状態となるようにすることができる。 By the above operation, when the manufacturing variation and assembly variation of components are the dominant factors, the same effect as in the first embodiment can be achieved. That is, even when the radial distance between the recording layer main spot R_MainLE and the recording layer sub-spot R_SubLS deviates from the track pitch Tp of the servo layer as shown in FIGS. 14A and 14C. By performing the track pitch adjustment described above, the control position of the recording layer sub-spot R_SubLS can be changed to the optimum position, and the state shown in FIG. 14B can be obtained.
　以上の実施例によれば、記録層ＳｕｂＳｐｏｔトラッキング制御を行う場合の課題を解決でき、記録層ＳｕｂＳｐｏｔトラッキング制御を適切に行うことが可能になる。 According to the above embodiment, the problem in the case of performing the recording layer SubSpot tracking control can be solved, and the recording layer SubSpot tracking control can be appropriately performed.
　即ち、光ディスク１０２と対物レンズの相対的な傾きが変化する場合であっても記録済みデータを上書きしてしまうことを防止し、グルーブレスディスクに対する情報の追加記録を行うことが可能になる。またその際、記録層トラックのトラックピッチをサーボ層のトラックピッチＴｐと精度良く一致させることが可能になり、良好なシーク性能や良好な再生性能を達成できる。更には、光ディスク１０２のデータ容量を確実に規定できる。 That is, even when the relative tilt between the optical disk 102 and the objective lens changes, it is possible to prevent overwriting recorded data and to perform additional recording of information on the grooveless disk. At that time, the track pitch of the recording layer track can be made to coincide with the track pitch Tp of the servo layer with high accuracy, and good seek performance and good reproduction performance can be achieved. Furthermore, the data capacity of the optical disk 102 can be defined reliably.
　このように本実施例によれば、グルーブレスディスクに対して適切に追加記録を行うことができる。 Thus, according to this embodiment, additional recording can be appropriately performed on the grooveless disc.
　以上の実施例では、図４を用いて説明したように、光ディスク１０２の構造として、記録膜を塗布された記録面が膜厚方向に積層された構造であるとした。しかし本発明の適用範囲は、図４の構造の光ディスクに限らない。フォーカスエラー信号を生成可能な記録層を有する光ディスクであれば適用可能である。 In the above embodiment, as described with reference to FIG. 4, the structure of the optical disc 102 is such that the recording surface coated with the recording film is laminated in the film thickness direction. However, the application range of the present invention is not limited to the optical disk having the structure shown in FIG. Any optical disc having a recording layer capable of generating a focus error signal can be applied.
　即ち、記録膜を塗布された記録面は存在せず、一様な媒体に対して波長４０５ｎｍのレーザ光が照射することで情報の記録もしくは再生が行われる光ディスクであっても、記録層フォーカスエラー信号を生成可能であれば情報記録面にフォーカス制御でき、その面内でのトラッキング制御について本発明を適用することができる。例えば、記録媒体内部における情報の記録位置を特定するための構造を一様な媒体中に有し、前記構造によってディテクタの出力信号から記録層フォーカスエラー信号を生成することで、面状に情報を記録して記録層を形成するような光ディスクに対しては、本発明を同様に適用することが可能である。 That is, there is no recording surface coated with a recording film, and the recording layer focus error may occur even in an optical disc in which information is recorded or reproduced by irradiating a uniform medium with a laser beam having a wavelength of 405 nm. If a signal can be generated, focus control can be performed on the information recording surface, and the present invention can be applied to tracking control within the surface. For example, a uniform medium has a structure for specifying the recording position of information in the recording medium, and a recording layer focus error signal is generated from the output signal of the detector by the structure, so that the information is obtained in a planar shape. The present invention can be similarly applied to an optical disc in which recording is performed to form a recording layer.
　更に以上の実施例の説明において光ディスク１０２はサーボ層を持つ構造としたが、本発明はサーボ層を持たない光ディスクに対しても、適用可能である。なぜなら本発明は記録層に２つのレーザスポットを配置し、片方のレーザスポットでトラッキングを行いながら他方のレーザスポットで記録発光を行う場合に、記録層に形成されるトラックピッチが設計目標値（以上の実施例ではＴｐ）からずれてしまう課題を解決するものである。そのため、本発明はサーボ層を持たない光ディスクに対しても、前記記録層に形成されるマーク列の半径方向の間隔を調整する点に関して、同様に適用可能である。 Further, in the above description of the embodiment, the optical disk 102 has a structure having a servo layer, but the present invention can also be applied to an optical disk having no servo layer. This is because, in the present invention, when two laser spots are arranged in the recording layer and tracking is performed with one laser spot and recording light emission is performed with the other laser spot, the track pitch formed in the recording layer is the design target value (above). In this embodiment, the problem of deviating from Tp) is solved. Therefore, the present invention can be similarly applied to an optical disc having no servo layer in that the radial distance between mark rows formed on the recording layer is adjusted.
　以上の実施例においては、例えば実施例１のステップＳ７０１にあるように、初回記録を行うのは、現在挿入されている光ディスクにとって初回の記録を指示された場合のみである。そのため、記録層が複数あった場合でも、そのうちの１つの層に対して初回記録を行って記録部を作成し、その記録部にてトラックピッチ調整を行った。そしてその他の記録層では前記の層でトラックピッチ調整を行った値を用いる動作とした。しかし各層で記録部を作成しトラックピッチ調整を行っても構わない。これにより、層間の厚みが均一でなく、一部の記録層で記録層が傾いていた場合であっても、より正確に記録層トラックのトラックピッチをサーボ層トラックピッチと同一に調整することができる。 In the above embodiment, for example, as in step S701 of the first embodiment, the first recording is performed only when the first recording is instructed for the currently inserted optical disk. Therefore, even when there are a plurality of recording layers, initial recording was performed on one of the layers to create a recording portion, and the track pitch was adjusted in the recording portion. The other recording layers were operated using the values obtained by adjusting the track pitch in the above layers. However, the recording portion may be created in each layer and the track pitch may be adjusted. As a result, even when the interlayer thickness is not uniform and the recording layer is inclined in some recording layers, the track pitch of the recording layer track can be adjusted more accurately to be the same as the servo layer track pitch. it can.
　以上の実施例では、初回記録を行う半経位置を光ディスク１０２の最内周とした。しかし初回記録を行う半径位置は、光ディスク１０２上のどの半径位置であってもよい。 In the above embodiment, the half-pitch position where the first recording is performed is the innermost circumference of the optical disc 102. However, the radial position where the initial recording is performed may be any radial position on the optical disc 102.
　また以上の実施例では、トラックピッチ調整は初回記録を行った半径位置において行う動作とした。しかし前述したように、トラックピッチ調整を行うには２トラック以上の記録された領域が存在すればよい。例えば、現在挿入されている光ディスクにとって初回記録でなく、記録面内に複数の記録部が存在する場合には、そのどの記録部を用いてトラックピッチ調整を行ってもよい。 In the above embodiment, the track pitch adjustment is performed at the radial position where the initial recording is performed. However, as described above, in order to adjust the track pitch, it is only necessary to have a recorded area of two or more tracks. For example, when the currently inserted optical disc is not the first recording but there are a plurality of recording portions in the recording surface, the track pitch may be adjusted using any of the recording portions.
　更に、以上の実施例における初回記録は、ホスト１１４から情報の記録を指示された後に行う動作としたが、それ以前に行っても良い。例えば、セットアップ処理にて行っても良い。 Furthermore, although the initial recording in the above embodiment is an operation performed after the host 114 is instructed to record information, it may be performed before that. For example, you may perform by a setup process.
　更に実施例１の初回記録に関しては、複数の半径位置で記録部を作成し、それぞれの記録部でトラックピッチ調整を行う動作としてもよい。複数の半径位置でトラックピッチ調整を実施し、その結果から半径位置に応じて記録層トラックピッチ調整電圧生成回路１５１４の出力する電圧Ｖ＿ＴｐＡｄｊの値を変えることで、光ディスク１０２の傾きが半径によって変わる場合であっても、記録層トラックのトラックピッチがサーボ層トラックピッチと同一になるように動作させることができる。半径位置に応じた電圧Ｖ＿ＴｐＡｄｊを決定する方法としては、その一例として、最内周と最外周でトラックピッチ調整を行い、その間の半径では最内周と最外周のそれぞれの調整結果を半径方向に線形補間する方法がある。 Further, for the initial recording of the first embodiment, it is possible to create a recording section at a plurality of radial positions and perform an operation of adjusting the track pitch at each recording section. When the track pitch adjustment is performed at a plurality of radial positions, and the value of the voltage V_TpAdj output from the recording layer track pitch adjustment voltage generation circuit 1514 is changed according to the radial position, thereby changing the inclination of the optical disk 102 depending on the radius Even so, it can be operated so that the track pitch of the recording layer track is the same as the servo layer track pitch. As an example of the method for determining the voltage V_TpAdj according to the radial position, the track pitch is adjusted at the innermost circumference and the outermost circumference. There is a method of linear interpolation.
　以上の実施例では記録層上に生じる２つのレーザスポットＲ＿ＭａｉｎＬＳ、Ｒ＿ＳｕｂＬＳの半径方向の距離は、サーボ層のトラックピッチＴｐに略等しくなるように配置した。しかしその距離はＴｐ以外でも構わない。例えばトラックピッチＴｐの整数倍でもよい。例えばその距離がトラックピッチＴｐの２倍である場合、記録中のトラックから２トラック離れた記録層トラック上に記録層サブスポットＲ＿ＳｕｂＬＳを照射することで、Ｔｐの２倍だけ外周側の位置に記録層メインスポットＲ＿ＭａｉｎＬＳの位置が制御され、情報が記録される。この場合にも、光ディスク１０２と対物レンズの相対的な傾きが変化した場合の記録済みデータの上書きは防止できるため、その場合にも記録層ＳｕｂＳｐｏｔトラッキング制御の利点は維持される。 In the above embodiment, the radial distance between the two laser spots R_MainLS and R_SubLS generated on the recording layer is arranged so as to be substantially equal to the track pitch Tp of the servo layer. However, the distance may be other than Tp. For example, it may be an integral multiple of the track pitch Tp. For example, when the distance is twice the track pitch Tp, the recording layer sub-spot R_SubLS is irradiated onto the recording layer track that is two tracks away from the recording track, thereby recording at a position on the outer circumference side by twice Tp. The position of the layer main spot R_MainLS is controlled and information is recorded. Also in this case, since overwriting of recorded data can be prevented when the relative inclination of the optical disc 102 and the objective lens changes, the advantage of the recording layer SubSpot tracking control is maintained also in that case.
　さらに記録層上に生じる２つのレーザスポットＲ＿ＭａｉｎＬＳ、Ｒ＿ＳｕｂＬＳの半径方向の距離は、サーボ層のトラックピッチＴｐの半分であっても構わない。トラックピッチＴｐの半分である場合は、特許文献２に記載のあるように例えばサーボ層がＤＶＤ－ＲＡＭのようにＣＡＰＡ（Ｃｏｍｐｌｉｍｅｎｔａｒｙ　Ａｌｌｏｃａｔｅｄ　Ｐｉｔ　Ａｄｄｒｅｓｓ）構造を持つ場合である。この場合、マークはランド及びグルーブの両方に記録されることになるため、マーク列の半径方向の間隔はトラックピッチの半分となる。 Further, the radial distance between the two laser spots R_MainLS and R_SubLS generated on the recording layer may be half of the track pitch Tp of the servo layer. The case where the track pitch is half of the track pitch Tp is a case where the servo layer has a CAPA (Complementary Allocated Pit Address) structure such as a DVD-RAM as described in Patent Document 2. In this case, since the marks are recorded on both the land and the groove, the distance between the mark rows in the radial direction is half the track pitch.
　更に、上記のように２つのレーザスポットＲ＿ＭａｉｎＬＳ、Ｒ＿ＳｕｂＬＳの半径方向の距離をＴｐではなくする場合に、初回記録に関する制約がどうなるかについて説明する。例えば実施例１におけるステップＳ７０５の初回記録では、ディスクの２回転以上は記録を行う必要があった。これに対し、レーザスポットＲ＿ＭａｉｎＬＳ、Ｒ＿ＳｕｂＬＳの半径方向の距離がサーボ層のトラックピッチＴｐのＮ倍（Ｎ：２以上の整数）の場合、初回記録で記録しなければいけないトラックの本数を考える。内周から外周に向かって情報を記録していく場合、トラックピッチ調整中は記録層サブスポットＲ＿ＳｕｂＬＳよりＮ本のトラックだけ外周側に記録されたトラックがある必要がある。さらにトラックピッチ調整はディスク１回転をかけて信号をモニタすることが望ましい。以上から、回転に同期して１トラックジャンプを行いながらトラックピッチ調整を行うには、（Ｎ＋１）トラック以上の記録された領域でトラックピッチ調整を行う必要がある。そのため初回記録に関して、ディスクの（Ｎ＋１）回転以上は記録を行う必要がある。 Furthermore, what will be the restrictions on the initial recording when the radial distance between the two laser spots R_MainLS and R_SubLS is not Tp as described above. For example, in the first recording in step S705 in the first embodiment, it is necessary to perform recording for two or more rotations of the disk. On the other hand, when the radial distance between the laser spots R_MainLS and R_SubLS is N times the track pitch Tp of the servo layer (N: an integer equal to or greater than 2), the number of tracks that must be recorded in the initial recording is considered. When recording information from the inner circumference toward the outer circumference, it is necessary to have tracks recorded on the outer circumference side by N tracks from the recording layer sub-spot R_SubLS during the track pitch adjustment. Further, it is desirable to monitor the signal by adjusting the track pitch over one rotation of the disk. From the above, in order to adjust the track pitch while performing one track jump in synchronization with the rotation, it is necessary to adjust the track pitch in the recorded area of (N + 1) tracks or more. Therefore, for the first recording, it is necessary to perform recording for more than (N + 1) rotations of the disk.
　次に、レーザスポットＲ＿ＭａｉｎＬＳ、Ｒ＿ＳｕｂＬＳの半径方向の距離がサーボ層のトラックピッチＴｐの半分の場合についても、初回記録で記録しなければいけないトラックの本数を考える。この場合、記録層トラックのトラックピッチはＴｐの半分になるが、レーザスポットＲ＿ＭａｉｎＬＳ、Ｒ＿ＳｕｂＬＳの半径方向の距離は記録層トラックのトラックピッチと同一になる。トラックピッチ調整は記録層に関する調整であるので、記録層において２トラック以上の記録された領域でトラックピッチ調整を行う必要がある点は実施例１と変わらない。即ちレーザスポットＲ＿ＭａｉｎＬＳ、Ｒ＿ＳｕｂＬＳの半径方向の距離がサーボ層のトラックピッチＴｐの半分の場合の初回記録においては、ディスクの２回転以上は記録を行う必要がある。 Next, consider the number of tracks that must be recorded in the initial recording even when the radial distance between the laser spots R_MainLS and R_SubLS is half the track pitch Tp of the servo layer. In this case, the track pitch of the recording layer track is half of Tp, but the distance in the radial direction of the laser spots R_MainLS and R_SubLS is the same as the track pitch of the recording layer track. Since the track pitch adjustment is an adjustment related to the recording layer, it is the same as in the first embodiment that the track pitch must be adjusted in an area where two or more tracks are recorded in the recording layer. That is, in the initial recording when the radial distance between the laser spots R_MainLS and R_SubLS is half the track pitch Tp of the servo layer, it is necessary to perform recording for two or more rotations of the disk.
　以上の実施例ではＲ＿ＳｕｂＴＥ信号をＤＰＤ法で生成するとしたが、それ以外の生成法を用いる場合も同様に適用可能である。例えば異なるトラッキングエラー信号の生成方法としてＤＰＰ法が知られており、この場合にも前述の負帰還領域に関する議論も含め、同様に適用できる。 In the above embodiment, the R_SubTE signal is generated by the DPD method. However, the present invention can be similarly applied when other generation methods are used. For example, the DPP method is known as a method for generating different tracking error signals, and in this case as well, it can be similarly applied, including the discussion regarding the negative feedback region described above.
　また以上の実施例では、光ディスク装置１０１が記録層トラックピッチ調整電圧生成回路１５１４を備え、記録層トラックピッチ調整電圧生成回路１５１４が出力する電圧Ｖ＿ＴｐＡｄｊを調整することでトラックピッチ調整を行う構成とした。しかし本発明は、記録層ＳｕｂＳｐｏｔトラッキング制御を行う場合に記録層に形成される記録層トラックのトラックピッチがＴｐからずれてしまうことを見出し、その課題に対する発明である。そのため、トラックピッチを調整する方法は、記録層トラックピッチ調整電圧生成回路１５１４が出力する電圧Ｖ＿ＴｐＡｄｊを調整する方法以外でも良い。 In the above embodiment, the optical disc apparatus 101 includes the recording layer track pitch adjustment voltage generation circuit 1514, and the track pitch adjustment is performed by adjusting the voltage V_TpAdj output from the recording layer track pitch adjustment voltage generation circuit 1514. . However, the present invention finds that the track pitch of the recording layer track formed in the recording layer deviates from Tp when performing the recording layer SubSpot tracking control, and is an invention for the problem. Therefore, the method of adjusting the track pitch may be other than the method of adjusting the voltage V_TpAdj output from the recording layer track pitch adjustment voltage generation circuit 1514.
　具体的には、光ピックアップ１０３が、記録層上に生じる２つのレーザスポットＲ＿ＭａｉｎＬＳ、Ｒ＿ＳｕｂＬＳの半径方向の距離を調整可能な光学素子を備え、その光学素子を用いて２つのレーザスポットの半径方向の距離を調整する構成としてもよい。 Specifically, the optical pickup 103 includes an optical element capable of adjusting a radial distance between two laser spots R_MainLS and R_SubLS generated on the recording layer, and the optical element 103 is used to adjust the radial distance between the two laser spots. The distance may be adjusted.
　以上の実施例では、トラッキングエラー信号にオフセットを印加する構成として、トラッキングエラー信号の電圧に対し、記録層トラックピッチ調整電圧生成回路１５１４が出力する電圧Ｖ＿ＴｐＡｄｊを加算器１５１５にて加算する構成とした。しかしオフセットの加算は、電圧の加算以外の形態をとっても良い。例えば信号処理回路１０５がデジタルのＬＳＩである場合、オフセットの印加はデジタル値の加算と読み替えることができることは自明である。 In the above embodiments, the offset is applied to the tracking error signal, and the voltage V_TpAdj output from the recording layer track pitch adjustment voltage generation circuit 1514 is added to the voltage of the tracking error signal by the adder 1515. . However, offset addition may take a form other than voltage addition. For example, when the signal processing circuit 105 is a digital LSI, it is obvious that application of an offset can be read as addition of a digital value.
　また以上の実施例において、記録層トラックピッチ調整電圧生成回路１５１４が出力する電圧Ｖ＿ＴｐＡｄｊを加算する記録層トラッキングエラー信号Ｒ＿ＴＥは、図２に示すサーボエラー信号生成回路１０４にて生成される。サーボエラー信号生成回路１０４内部の各エラー信号生成回路は、総光量によるＡＧＣ（Ａｕｔｏ　Ｇａｉｎ　Ｃｏｎｔｒｏｌ）を行うことが好ましい。記録層Ｓｕｂトラッキングエラー信号生成回路１４０１が総光量によるＡＧＣ、即ちディテクタ１３２４で受光した全電気信号による正規化を行うことで、例えば手前の記録層の記録状態によって反射光量が変化した場合であってもその影響を除去できる。そのため、記録層トラックピッチ調整電圧生成回路１５１４が出力する電圧Ｖ＿ＴｐＡｄｊを加算する値は、手前の記録層の記録状態によらず一定とすることができる。 In the above embodiment, the recording layer tracking error signal R_TE to which the voltage V_TpAdj output from the recording layer track pitch adjustment voltage generation circuit 1514 is added is generated by the servo error signal generation circuit 104 shown in FIG. Each error signal generation circuit in the servo error signal generation circuit 104 preferably performs AGC (Auto Gain Control) based on the total light amount. The recording layer sub-tracking error signal generation circuit 1401 performs normalization based on the AGC based on the total light amount, that is, the total electric signal received by the detector 1324, so that, for example, the reflected light amount changes depending on the recording state of the front recording layer. Can also remove the effect. Therefore, the value to which the voltage V_TpAdj output from the recording layer track pitch adjustment voltage generation circuit 1514 is added can be constant regardless of the recording state of the previous recording layer.
　以上の実施例では、記録層トラックピッチ調整電圧生成回路１５１４が出力する電圧Ｖ＿ＴｐＡｄｊが加算する対象として、記録層トラッキング制御回路１５１６の入力信号であるＲ＿ＴＥ信号としたが、電圧Ｖ＿ＴｐＡｄｊを加算する位置は記録層トラッキング制御回路１５１６の内部の信号であってもよい。 In the above embodiment, the voltage V_TpAdj output from the recording layer track pitch adjustment voltage generation circuit 1514 is added as the R_TE signal that is the input signal of the recording layer tracking control circuit 1516, but the position where the voltage V_TpAdj is added is It may be a signal inside the recording layer tracking control circuit 1516.
　なお、以上の実施例ではレーザダイオード１３０２とレーザダイオード１３１５を駆動するために同一のレーザパワー制御回路１３０１を用いたが、それぞれのレーザダイオードに固有のレーザパワー制御回路を備えても良い。また、球面収差補正素子１３０９は、４０５ｎｍの光学系および６５０ｎｍの光学系の両方に影響する位置に配置されてもよく、たとえば１／４波長板１３１０とダイクロイックミラー１３０８の間に設置しても良い。 In the above embodiment, the same laser power control circuit 1301 is used to drive the laser diode 1302 and the laser diode 1315. However, each laser diode may be provided with a laser power control circuit unique to each laser diode. The spherical aberration correction element 1309 may be disposed at a position that affects both the 405 nm optical system and the 650 nm optical system. For example, the spherical aberration correction element 1309 may be disposed between the quarter wavelength plate 1310 and the dichroic mirror 1308. .
（光ディスクの形態）
  図２０に、本実施例が対象とする光ディスク222の構造(断面)を示す。同図の光ディスク222は、溝が形成されたガイド層を一つと、溝が無くフラットな記録層を一または複数有した光ディスク222である。ガイド層の溝は、ＤＶＤやＢＤといったディスクに見られるような溝と同様に、ディスク回転軸を中心とした螺旋状の溝である。
溝は、ＤＶＤやＢＤといったディスクに見られるように長さ方向に略一定周期のうねり構造（ウォブル）を持っている。
また、ガイド層には図示しないがDVDやBDといったディスクに見られるように現在の位置（アドレス）を示す情報が付加されている。
アドレスの付加の方法は例えば、ウォブルに変調する部分を追加する、溝構造にピットを付加する等がある。 (Optical disc form)
FIG. 20 shows the structure (cross section) of an optical disc 222 targeted by this embodiment. The optical disk 222 shown in the figure is an optical disk 222 having one guide layer with grooves and one or more flat recording layers without grooves. The groove of the guide layer is a spiral groove centered on the disk rotation axis, like the groove found on a disk such as DVD or BD.
The groove has a undulation structure (wobble) having a substantially constant period in the length direction as seen in a disk such as a DVD or a BD.
Although not shown, information indicating the current position (address) is added to the guide layer so as to be seen on a disc such as a DVD or a BD.
For example, a method of adding an address includes adding a portion to be modulated to wobble and adding a pit to the groove structure.
　また、同図の対物レンズ311は、光ディスク222にレーザ光線を集光するための光ディスク記録再生装置(図示せず)の対物レンズ311である。同図は、対物レンズ311を異なる２つの光束が通過し、一つの光束が、光ディスク222のガイド層にレーザスポットLSgを生じさせ、もう一つの光束が、光ディスク222の複数ある記録層のうちの一つにレーザスポットLSwを生じさせていることを示している。本実施例が対象とする光ディスク222は、このように２つあるいは、２つ以上の光束を用いて記録または再生を行う。
（光ディスク記録再生装置の形態）
　図１９は、本発明に従う光ディスク記録再生装置221の一実施例を示すブロック構成図である。 Further, the objective lens 311 in the figure is an objective lens 311 of an optical disc recording / reproducing apparatus (not shown) for condensing a laser beam on the optical disc 222. In the figure, two different light beams pass through the objective lens 311, one light beam generates a laser spot LSg on the guide layer of the optical disk 222, and the other light beam is out of a plurality of recording layers of the optical disk 222. One shows that the laser spot LSW is generated. In this way, the optical disk 222 targeted by this embodiment performs recording or reproduction using two or two or more light beams.
(Configuration of optical disc recording / reproducing apparatus)
FIG. 19 is a block diagram showing an embodiment of the optical disc recording / reproducing apparatus 221 according to the present invention.
　光ディスク記録再生装置221は装置に装着された光ディスク222にレーザ光を照射することで情報の記録または再生を行い、SATA(Serial Advanced Technology Attachment)などのインターフェースを通じてPC(Personal Computer）などのホスト223と通信を行う。
光ディスク記録再生装置221は、コントローラ201と信号処理手段202と、光ピックアップ203と、光ピックアップ203を光ディスク222の半径方向に移動するスライダモータ204と、スライダモータ204を駆動するスライダ駆動手段205と、光ピックアップ203中に備えられた球面収差補正素子309を駆動するための収差補正駆動手段206と、光ディスク222を回転するためのスピンドルモータ207と、スピンドルモータ207を回転させるための回転信号を生成するスピンドル制御手段208と、スピンドル制御手段208が生成する回転信号に応じてスピンドルモータ207を駆動すると共にスピンドルモータ207の回転速度に対応した周波数のＦＧ信号を生成するスピンドル駆動手段209と、光ディスク222の記録層とレーザスポットLSwの焦点位置とのずれ量を示す記録層フォーカス誤差信号を生成するフォーカス誤差信号生成手段211と、記録層フォーカス誤差信号に応じてフォーカス駆動信号を生成するフォーカス制御手段212と、フォーカス駆動信号に応じて光ピックアップ203中に備えられたアクチュエータ312を駆動するフォーカス駆動手段213と、記録層トラックと記録層上の光スポット500もしくは光スポット501もしくは光スポット502の位置のずれ量を示す記録層トラッキング誤差信号を生成するトラッキング誤差信号生成手段214と、光ディスク222のガイド層トラックとガイド層上のレーザスポットLSgとの位置ずれ量を示すガイド層トラッキング誤差信号を生成するトラッキング誤差信号生成手段210と、記録層トラッキング誤差信号或いはガイド層トラッキング誤差信号に応じてトラッキング駆動信号を生成するトラッキング制御手段215と、トラッキング駆動信号に応じてアクチュエータ312を駆動するトラッキング駆動手段216と、光ディスク222のガイド層とレーザスポットLSgの焦点位置とのずれ量を示すガイド層フォーカス誤差信号を生成するフォーカス誤差信号生成手段217と、ガイド層フォーカス誤差信号に応じたリレーレンズ駆動信号を生成するリレーレンズ制御手段218と、トラッキング駆動信号及びリレーレンズ駆動信号に応じてリレーレンズ321を駆動するリレーレンズ駆動手段219を備えている。 The optical disk recording / reproducing apparatus 221 records or reproduces information by irradiating an optical disk 222 mounted on the apparatus with laser light, and communicates with a host 223 such as a PC (Personal Computer) through an interface such as SATA (Serial Advanced Technology Attachment). Communicate.
The optical disc recording / reproducing apparatus 221 includes a controller 201, a signal processing unit 202, an optical pickup 203, a slider motor 204 that moves the optical pickup 203 in the radial direction of the optical disc 222, a slider driving unit 205 that drives the slider motor 204, Aberration correction driving means 206 for driving the spherical aberration correction element 309 provided in the optical pickup 203, a spindle motor 207 for rotating the optical disk 222, and a rotation signal for rotating the spindle motor 207 are generated. Spindle control means 208, spindle drive means 209 for driving the spindle motor 207 in accordance with the rotation signal generated by the spindle control means 208 and generating an FG signal having a frequency corresponding to the rotation speed of the spindle motor 207, and the optical disc 222 Recording layer focus error indicating the amount of deviation between the recording layer and the focal position of the laser spot LSW A focus error signal generating unit 211 for generating a signal, a focus control unit 212 for generating a focus drive signal in accordance with the recording layer focus error signal, and an actuator 312 provided in the optical pickup 203 in accordance with the focus drive signal Focus driving means 213 for performing recording, tracking error signal generating means 214 for generating a recording layer tracking error signal indicating the amount of displacement between the recording layer track and the light spot 500 or the light spot 501 or the light spot 502 on the recording layer, and an optical disc Tracking error signal generating means 210 for generating a guide layer tracking error signal indicating the amount of positional deviation between the guide layer track 222 and the laser spot LSg on the guide layer, and according to the recording layer tracking error signal or the guide layer tracking error signal Tracking to generate tracking drive signal A control unit 215, a tracking drive unit 216 that drives the actuator 312 in response to the tracking drive signal, and a focus error that generates a guide layer focus error signal indicating the amount of deviation between the guide layer of the optical disc 222 and the focal position of the laser spot LSg A signal generation unit 217; a relay lens control unit 218 that generates a relay lens drive signal according to the guide layer focus error signal; and a relay lens drive unit 219 that drives the relay lens 321 according to the tracking drive signal and the relay lens drive signal. It has.
　光ピックアップ203はガイド層にサーボ制御を行うとともに、ディスク上の位置に対応したアドレス及びディスク固有の情報を再生するためのガイド層光学系と、ガイド層からの距離が異なる複数の記録層にデータを記録・再生するための記録層光学系で構成されている。 The optical pickup 203 performs servo control on the guide layer, and data on a guide layer optical system for reproducing an address and disc-specific information corresponding to the position on the disc, and a plurality of recording layers at different distances from the guide layer. Is composed of a recording layer optical system for recording / reproducing data.
　まず、記録層光学系の動作について説明する。レーザドライバ301は、コントローラ201によって制御されており、レーザダイオード302を駆動する電流を出力する。この駆動電流は、レーザノイズを抑制するために数百MHzの高周波重畳が印加されている。レーザダイオード302は、駆動電流に応じた波形で例えば波長405nmのレーザ光LBwを出射する。出射されたレーザ光はコリメータレンズ303にて平行光となり、ビームスプリッタ304で一部が反射し、集光レンズ305によってパワーモニタ306に集光する。パワーモニタ306は、レーザ光の強度に応じた電流または電圧をコントローラ201にフィードバックする。これによって光ディスク222の記録層に集光するレーザ光LBwの強度が、たとえば２mWなど所望の値に保持される。一方、ビームスプリッタ304を透過したレーザ光LBwは偏光ビームスプリッタ307にて反射し、収差補正駆動手段206にて駆動される球面収差補正素子309によって収束・発散が制御され、ダイクロイックミラー308を透過する。ダイクロイックミラー308は特定の波長の光を反射し、その他の波長の光を透過する光学素子である。ここでは波長405nmの光を透過し、650nmの光を反射するものとする。ダイクロイックミラー308を透過したレーザ光LBwは、1/4波長板310にて円偏光となり、対物レンズ311によって光ディスク222の記録層にレーザスポットLSwとして集光する。ここで、球面収差補正素子309はコントローラ201から収差補正駆動手段206を介してグルーブレスディスクの記録層に応じた所定の位置となるように制御が行われる。光ディスク222によって反射したレーザ光LBwは、光ディスク222に記録された情報に応じて強度が変調される。1/4波長板310にて直線偏光となり、ダイクロイックミラー308を経て、偏光ビームスプリッタ307および球面収差補正素子309を透過する。透過したレーザ光LSwは、集光レンズ313によってディテクタ314に集光する。ディテクタ314はレーザ光LBwの強度を検出し、これに応じた信号を信号処理手段202に出力する。またフォーカス誤差信号生成手段211は、ディテクタ314から出力された信号から、記録層に対する記録層フォーカス誤差信号を生成する。フォーカス制御手段212はコントローラ201からの指令信号により、フォーカス誤差信号に対応したフォーカス駆動信号をフォーカス駆動手段213に出力する。フォーカス駆動手段213はフォーカス駆動信号に応じてアクチュエータ312を駆動することで記録面に垂直の方向に対物レンズ311の位置を変位させ、記録層にレーザ光LBwが合焦するように記録層フォーカスサーボ制御を行う。ディテクタ314から出力された信号はトラッキング誤差信号生成手段214にも入力され、記録層に対する記録層トラッキング誤差信号を生成する。 First, the operation of the recording layer optical system will be described. The laser driver 301 is controlled by the controller 201 and outputs a current for driving the laser diode 302. This drive current is applied with high frequency superposition of several hundred MHz in order to suppress laser noise. The laser diode 302 emits a laser beam LBw having a wavelength of 405 nm, for example, with a waveform corresponding to the drive current. The emitted laser light becomes parallel light by the collimator lens 303, a part of the light is reflected by the beam splitter 304, and is condensed on the power monitor 306 by the condenser lens 305. The power monitor 306 feeds back a current or voltage corresponding to the intensity of the laser light to the controller 201. As a result, the intensity of the laser beam LBw focused on the recording layer of the optical disc 222 is maintained at a desired value such as 2 mW. On the other hand, the laser beam LBw that has passed through the beam splitter 304 is reflected by the polarization beam splitter 307, and the convergence / divergence is controlled by the spherical aberration correction element 309 driven by the aberration correction drive means 206, and passes through the dichroic mirror 308. . The dichroic mirror 308 is an optical element that reflects light of a specific wavelength and transmits light of other wavelengths. Here, it is assumed that light having a wavelength of 405 nm is transmitted and light having a wavelength of 650 nm is reflected. The laser beam LBw that has passed through the dichroic mirror 308 becomes circularly polarized light by the quarter-wave plate 310 and is condensed as a laser spot LSW on the recording layer of the optical disc 222 by the objective lens 311. Here, the spherical aberration correction element 309 is controlled from the controller 201 via the aberration correction driving means 206 so as to be at a predetermined position corresponding to the recording layer of the grooveless disk. The intensity of the laser beam LBw reflected by the optical disc 222 is modulated in accordance with information recorded on the optical disc 222. The light is linearly polarized by the quarter-wave plate 310, passes through the dichroic mirror 308, and passes through the polarization beam splitter 307 and the spherical aberration correction element 309. The transmitted laser light LSW is condensed on the detector 314 by the condenser lens 313. The detector 314 detects the intensity of the laser beam LBw and outputs a signal corresponding to the intensity to the signal processing means 202. The focus error signal generation unit 211 generates a recording layer focus error signal for the recording layer from the signal output from the detector 314. The focus control unit 212 outputs a focus drive signal corresponding to the focus error signal to the focus drive unit 213 in response to a command signal from the controller 201. The focus drive unit 213 drives the actuator 312 according to the focus drive signal to displace the position of the objective lens 311 in the direction perpendicular to the recording surface, and the recording layer focus servo so that the laser beam LBw is focused on the recording layer. Take control. The signal output from the detector 314 is also input to the tracking error signal generation unit 214 to generate a recording layer tracking error signal for the recording layer.
　図２８にトラッキング誤差信号生成手段214の内部構成を示す。
トラッキング誤差信号生成手段214は、光スポット502よりトラッキング誤差信号を生成する前SUBトラッキング誤差信号生成手段1101と光スポット500よりトラッキング誤差信号を生成するMainトラッキング誤差信号生成手段1102と光スポット501よりトラッキング誤差信号を生成する後SUBトラッキング誤差信号生成手段1103と記録、再生、OPC時等の状態により出力するトラッキング誤差信号を選択するトラッキング誤差信号選択手段1104を備えている。 FIG. 28 shows an internal configuration of the tracking error signal generation unit 214.
The tracking error signal generation unit 214 performs tracking using the light spot 501 and the SUB tracking error signal generation unit 1101 that generates the tracking error signal from the light spot 502 and the main tracking error signal generation unit 1102 that generates the tracking error signal from the light spot 500. Subsequent to generating an error signal, a SUB tracking error signal generating unit 1103 and a tracking error signal selecting unit 1104 for selecting a tracking error signal to be output depending on a state such as recording, reproduction, and OPC are provided.
　トラッキング誤差信号選択手段1104は、例えば情報の再生時は、Mainトラッキング誤差信号生成手段1102より生成されたトラッキング誤差信号を出力し、記録時は後Subトラッキング誤差信号生成手段1103より生成されたトラッキング誤差信号を出力し、OPC時には後に記載するように出力するトラッキング誤差信号を切り替える形で動作する。
ここで、本実施例では、図１８に示すように、記録層に集光させる光スポット500から502が３つである。その為、トラッキング誤差信号生成手段を前SUBトラッキング誤差信号生成手段1101とMainトラッキング誤差信号生成手段1102と後SUBトラッキング誤差信号生成手段1103の３つとしたが、トラッキング誤差信号生成手段214が出力できるトラッキング誤差信号は記録再生に使用する光スポット500に加え１つ以上の光スポットからトラッキング誤差信号を生成できれば本実施例を実施可能である。
トラッキング制御手段215ではコントローラ201からの制御信号によりトラッキング誤差信号生成手段214或いはトラッキング誤差信号生成手段210の出力に対応したトラッキング駆動信号をトラッキング駆動手段216に出力する。 The tracking error signal selection unit 1104 outputs, for example, the tracking error signal generated by the Main tracking error signal generation unit 1102 when reproducing information, and the tracking error generated by the subsequent Sub tracking error signal generation unit 1103 during recording. It operates by switching the tracking error signal to be output as described later during OPC.
Here, in this embodiment, as shown in FIG. 18, there are three light spots 500 to 502 focused on the recording layer. For this reason, there are three tracking error signal generating means: the front SUB tracking error signal generating means 1101, the main tracking error signal generating means 1102, and the rear SUB tracking error signal generating means 1103. However, the tracking error signal generating means 214 can output the tracking error signal. This embodiment can be implemented if the error signal can be generated from one or more light spots in addition to the light spot 500 used for recording and reproduction.
The tracking control unit 215 outputs a tracking drive signal corresponding to the output of the tracking error signal generation unit 214 or the tracking error signal generation unit 210 to the tracking drive unit 216 according to a control signal from the controller 201.
　次に、ガイド層光学系について説明する。記録層光学系と同様に、レーザドライバ301はコントローラ201によって制御されており、レーザダイオード315を駆動する電流を出力する。レーザダイオード315は例えば波長650nmのレーザ光LBgを出射する。レーザ光LBgの一部は、コリメータレンズ316、ビームスプリッタ317、集光レンズ318を経て、パワーモニタ319にてパワーがモニタされる。モニタしたパワーをコントローラ201にフィードバックすることで、光ディスク222のガイド層に集光するレーザ光LBgの強度が、たとえば3mWなど所望のパワーに保持される。ビームスプリッタ317を透過したレーザ光LBgは、偏光ビームスプリッタ320を透過し、リレーレンズ321にて収束・発散・光軸変化の制御が行われる。リレーレンズ321を経たレーザ光LBgは、ダイクロイックミラー308にて反射し、1/4波長板310を経て、対物レンズ311により光ディスク222のガイド層にレーザスポットLSgとして集光する。光ディスク222にて反射したレーザ光LBgを偏光ビームスプリッタ320にて反射し、集光レンズ322にてディテクタ323に集光する。 Next, the guide layer optical system will be described. Similar to the recording layer optical system, the laser driver 301 is controlled by the controller 201 and outputs a current for driving the laser diode 315. The laser diode 315 emits laser light LBg having a wavelength of 650 nm, for example. A part of the laser beam LBg is monitored by a power monitor 319 through a collimator lens 316, a beam splitter 317, and a condenser lens 318. By feeding back the monitored power to the controller 201, the intensity of the laser beam LBg focused on the guide layer of the optical disc 222 is maintained at a desired power such as 3 mW. The laser beam LBg that has passed through the beam splitter 317 passes through the polarization beam splitter 320 and is controlled by the relay lens 321 to converge, diverge, and change the optical axis. The laser beam LBg that has passed through the relay lens 321 is reflected by the dichroic mirror 308, passes through the quarter-wave plate 310, and is condensed as a laser spot LSg on the guide layer of the optical disc 222 by the objective lens 311. The laser beam LBg reflected by the optical disk 222 is reflected by the polarization beam splitter 320 and condensed on the detector 323 by the condenser lens 322.
　ディテクタ323ではレーザ光の強度を検出し、これに応じた信号を信号処理手段202に出力する。信号処理手段202は、ディテクタ323から出力されるガイド層にウォブルして形成されたトラックに対応した信号により光ディスク222の回転を制御するための同期信号、記録或いは再生を行う際の基準となるクロック信号を生成するとともに、レーザスポットLSgが追従している光ディスク222上の位置に対応したアドレスを再生してコントローラ201に出力する。信号処理手段202から出力される同期信号とスピンドル駆動手段209から出力されるＦＧ信号はスピンドル制御手段208に入力される。スピンドル制御手段208ではコントローラ201からの制御信号により、光ディスク222を角速度一定で回転させる場合にはスピンドルモータ207の回転速度に対応した周波数のＦＧ信号に基づいたスピンドル駆動信号を出力し、光ディスク222を線速度一定で回転させる場合にはガイド層から再生された同期信号に基づいたスピンドル駆動信号を出力する。スピンドル駆動手段209ではスピンドル駆動信号に応じてスピンドルモータ207を駆動することで光ディスク222の回転数が所定の値となるようにスピンドル制御が行われる。フォーカス誤差信号生成手段217はディテクタ323から出力された信号から光ディスク222のガイド層とレーザスポットLSgの合焦位置とのずれに対応したガイド層フォーカス誤差信号を生成し、リレーレンズ制御手段218はガイド層フォーカス誤差信号に応じたリレーレンズ駆動信号を生成する。リレーレンズ駆動手段219はリレーレンズ駆動信号に応じてリレーレンズ321を駆動することで、レーザスポットLSgがガイド層で合焦するようにガイド層フォーカスサーボ制御を行う。また、リレーレンズ駆動手段219は、トラッキング駆動信号によりリレーレンズ321を光軸を変化させるように駆動させる事で、レーザスポットLSgとレーザスポットLSwの半径方向の相対位置を変化させる。また、トラッキング誤差信号生成手段210は、ディテクタ323から出力された信号から、光ディスク222のガイド層のトラックとレーザスポットLSgの位置のずれに対応したガイド層トラッキング誤差信号を生成し、トラッキング制御手段215に出力する。トラッキング制御手段215ではコントローラ201からの制御信号によりトラッキング誤差信号生成手段214或いはトラッキング誤差信号生成手段210の出力に対応したトラッキング駆動信号をトラッキング駆動手段216に出力する。 Detector 323 detects the intensity of the laser beam and outputs a signal corresponding to this to signal processing means 202. The signal processing means 202 is a synchronization signal for controlling the rotation of the optical disc 222 by a signal corresponding to a track formed by wobbling the guide layer output from the detector 323, and a clock used as a reference for recording or reproduction A signal is generated, and an address corresponding to the position on the optical disc 222 that the laser spot LSg follows is reproduced and output to the controller 201. The synchronization signal output from the signal processing unit 202 and the FG signal output from the spindle driving unit 209 are input to the spindle control unit 208. The spindle control means 208 outputs a spindle drive signal based on an FG signal having a frequency corresponding to the rotational speed of the spindle motor 207 when the optical disk 222 is rotated at a constant angular velocity by the control signal from the controller 201, and the optical disk 222 is When rotating at a constant linear velocity, a spindle drive signal based on the synchronization signal reproduced from the guide layer is output. The spindle driving means 209 performs spindle control so that the rotational speed of the optical disc 222 becomes a predetermined value by driving the spindle motor 207 in accordance with the spindle driving signal. The focus error signal generation unit 217 generates a guide layer focus error signal corresponding to the deviation between the guide layer of the optical disc 222 and the in-focus position of the laser spot LSg from the signal output from the detector 323, and the relay lens control unit 218 A relay lens driving signal corresponding to the layer focus error signal is generated. The relay lens driving means 219 performs guide layer focus servo control so that the laser spot LSg is focused on the guide layer by driving the relay lens 321 according to the relay lens drive signal. The relay lens driving means 219 changes the relative position in the radial direction between the laser spot LSg and the laser spot LSw by driving the relay lens 321 to change the optical axis according to the tracking drive signal. Further, the tracking error signal generation unit 210 generates a guide layer tracking error signal corresponding to the positional deviation between the track of the guide layer of the optical disc 222 and the laser spot LSg from the signal output from the detector 323, and the tracking control unit 215 Output to. The tracking control unit 215 outputs a tracking drive signal corresponding to the output of the tracking error signal generation unit 214 or the tracking error signal generation unit 210 to the tracking drive unit 216 according to a control signal from the controller 201.
　記録層に記録を行う際には、フォーカス誤差信号生成手段211から出力される記録層フォーカス誤差信号に基づいて生成されたフォーカス駆動信号によりアクチュエータ312を駆動することで記録層にレーザスポットLSwが記録層で合焦するように記録層フォーカスサーボ制御が行われ、フォーカス誤差信号生成手段217から出力されるガイド層フォーカス誤差信号に基づいて生成されたリレーレンズ駆動信号によりリレーレンズ321を駆動することでガイド層にレーザスポットLSgが記録層で合焦するようにガイド層フォーカスサーボ制御が行われる。 When recording on the recording layer, the laser spot LSW is recorded on the recording layer by driving the actuator 312 with the focus drive signal generated based on the recording layer focus error signal output from the focus error signal generating unit 211. The recording layer focus servo control is performed so as to focus on the layer, and the relay lens 321 is driven by the relay lens drive signal generated based on the guide layer focus error signal output from the focus error signal generation unit 217. Guide layer focus servo control is performed so that the laser spot LSg is focused on the guide layer in the recording layer.
　また、コントローラ201からの制御信号によりトラッキング制御手段215からはトラッキング誤差信号生成手段214或いはトラッキング誤差信号生成手段210から出力されるトラッキング誤差信号に基づいて生成されたトラッキング駆動信号がトラッキング駆動手段216に出力される。トラッキング駆動手段216はトラッキング駆動信号に応じてアクチュエータ312及びリレーレンズ321を駆動することでガイド層のトラックをレーザスポットLSgが追従し、記録を行わない光スポット501もしくは光スポット502が記録層の記録マーク列を追従するようにトラッキングサーボ制御が行われる。また、コントローラ201からの制御信号を受けたスライダ制御手段220ではトラッキング駆動信号の平均値に基づいてスライダモータ204を駆動するスライダ駆動信号を出力する。このスライダ駆動信号に従ってスライダ駆動手段205によりスライダモータ204を駆動し、アクチュエータ312がディスク半径方向可動範囲の中心位置近傍で動作するように光ピックアップ203をディスク半径方向に移送する。ホスト223から入力された記録層に記録するデータ及びデータを記録する光ディスク222上の位置に対応したアドレス情報がコントローラ201から信号処理手段202に出力される。信号処理手段202では入力されたデータ及びアドレス情報をガイド層から再生された基準クロック信号に基づいて所定の方式で変調し、レーザドライバ301に出力する。レーザドライバ301は信号処理手段202の出力に応じた駆動電流をレーザダイオード302に出力し、レーザダイオード302が対応した強度でレーザ光LBwを出射することで光ディスク222の記録層に記録が行われる。これにより、記録を行う光スポット500とサーボ制御を行う光スポット５０１もしくは光スポット５０２の焦点の間隔で記録層に記録を行う事が出来る。光スポット500とサーボ制御を行う光スポット５０１もしくは光スポット５０２の焦点の間隔をガイド層のトラック間隔と一致させておく事で、ガイド層のトラックのスパイラルと同様の軌跡で記録層に情報の記録を行う事が出来る。また、ガイド層のトラックが内周から外周に向かってスパイラル状に形成されている場合にトラッキングサーボ制御に使用する光スポットを光スポット501に使用したとすると、ガイド層のトラックが外周から内周に向かってスパイラル上に形成されている場合では、光スポット502を記録層のトラッキングサーボ制御に使用すると外周から内周にスパイラル状に記録マークを形成する事が出来る。 In addition, the tracking drive signal generated based on the tracking error signal output from the tracking error signal generating unit 214 or the tracking error signal generating unit 210 from the tracking control unit 215 by the control signal from the controller 201 is sent to the tracking driving unit 216. Is output. The tracking drive means 216 drives the actuator 312 and the relay lens 321 according to the tracking drive signal, so that the laser spot LSg follows the track of the guide layer, and the light spot 501 or the light spot 502 that does not perform recording is recorded on the recording layer. Tracking servo control is performed so as to follow the mark row. The slider control means 220 that receives the control signal from the controller 201 outputs a slider drive signal for driving the slider motor 204 based on the average value of the tracking drive signal. In accordance with this slider drive signal, the slider motor 204 is driven by the slider drive means 205, and the optical pickup 203 is moved in the disk radial direction so that the actuator 312 operates in the vicinity of the center position of the movable range in the disk radial direction. Data to be recorded on the recording layer input from the host 223 and address information corresponding to the position on the optical disc 222 where the data is recorded are output from the controller 201 to the signal processing means 202. The signal processing means 202 modulates the input data and address information by a predetermined method based on the reference clock signal reproduced from the guide layer, and outputs it to the laser driver 301. The laser driver 301 outputs a drive current corresponding to the output of the signal processing means 202 to the laser diode 302, and the laser diode 302 emits the laser beam LBw with a corresponding intensity, so that recording is performed on the recording layer of the optical disc 222. Thus, recording can be performed on the recording layer at the focal distance between the light spot 500 for recording and the light spot 501 or the light spot 502 for servo control. By recording the light spot 500 and the light spot 501 or servo spot 502 for which servo control is performed at the same focal distance as the track spacing of the guide layer, information is recorded on the recording layer in the same locus as the spiral of the guide layer track. Can be done. If the light spot used for tracking servo control is used as the light spot 501 when the guide layer track is spirally formed from the inner periphery to the outer periphery, the guide layer track is changed from the outer periphery to the inner periphery. When the light spot 502 is used for tracking servo control of the recording layer, a recording mark can be formed in a spiral shape from the outer periphery to the inner periphery.
　記録層に記録された情報を再生する場合には、フォーカス誤差信号生成手段211から出力される記録層フォーカス誤差信号に基づいて生成されたフォーカス駆動信号によりアクチュエータ312を駆動することで記録層にレーザスポットLSwが記録層で合焦するように記録層フォーカスサーボ制御が行われる。また、フォーカス誤差信号生成手段217から出力されるガイド層フォーカス誤差信号に基づいて生成されたリレーレンズ駆動信号によりリレーレンズ321を駆動することでガイド層にレーザスポットLSgがガイド層で合焦するようにガイド層フォーカスサーボ制御が行われる。また、記録層に記録された情報の軌跡からなるトラックと記録層に照射された光スポット500とのずれに対応したトラッキング誤差信号がトラッキング誤差検出手段214から出力される。コントローラ201からの制御信号によりトラッキング制御手段215からはトラッキング誤差信号生成手段214から出力される記録層トラッキング誤差信号に基づいて生成されたトラッキング駆動信号がトラッキング駆動手段216に出力される。トラッキング駆動手段216はトラッキング駆動信号に応じてアクチュエータ312を駆動することで記録層に記録された情報の軌跡からなるトラックを光スポット500が追従するようにトラッキングサーボ制御が行われ、ディテクタ314から記録層からの再生信号が出力される。また、コントローラ201からの制御信号を受けたスライダ制御手段220ではトラッキング駆動信号の平均値に基づいてスライダモータ204を駆動するスライダ駆動信号を出力する。このスライダ駆動信号に従ってスライダ駆動手段205によりスライダモータ204を駆動し、アクチュエータ312がディスク半径方向可動範囲の中心位置近傍で動作するように光ピックアップ203をディスク半径方向に移送する。信号処理手段202では入力された再生信号から光ディスク222の回転を制御するための同期信号、再生を行う際の基準となるクロック信号を生成する。また、信号処理手段202は再生信号に対して増幅、等化、復号などの処理を行い、復号したデータ及びデータの光ディスク222上の位置に対応したアドレス情報をコントローラ201に出力する。コントローラ201は再生したデータをホスト223に出力する。 When reproducing the information recorded on the recording layer, the actuator 312 is driven by the focus drive signal generated based on the recording layer focus error signal output from the focus error signal generating means 211, thereby causing the recording layer to laser. Recording layer focus servo control is performed so that the spot LSW is focused on the recording layer. Further, by driving the relay lens 321 with the relay lens driving signal generated based on the guide layer focus error signal output from the focus error signal generating means 217, the laser spot LSg is focused on the guide layer at the guide layer. The guide layer focus servo control is performed. The tracking error detection unit 214 outputs a tracking error signal corresponding to the deviation between the track formed by the locus of information recorded on the recording layer and the light spot 500 irradiated on the recording layer. A tracking drive signal generated based on the recording layer tracking error signal output from the tracking error signal generation unit 214 is output from the tracking control unit 215 to the tracking drive unit 216 by the control signal from the controller 201. The tracking drive means 216 drives the actuator 312 according to the tracking drive signal, and tracking servo control is performed so that the light spot 500 follows the track formed by the locus of information recorded on the recording layer, and recording is performed from the detector 314. A reproduction signal from the layer is output. The slider control means 220 that receives the control signal from the controller 201 outputs a slider drive signal for driving the slider motor 204 based on the average value of the tracking drive signal. In accordance with this slider drive signal, the slider motor 204 is driven by the slider drive means 205, and the optical pickup 203 is moved in the disk radial direction so that the actuator 312 operates in the vicinity of the center position of the movable range in the disk radial direction. The signal processing means 202 generates a synchronization signal for controlling the rotation of the optical disc 222 and a clock signal serving as a reference for reproduction from the input reproduction signal. The signal processing unit 202 performs processing such as amplification, equalization, and decoding on the reproduction signal, and outputs the decoded data and address information corresponding to the position of the data on the optical disk 222 to the controller 201. The controller 201 outputs the reproduced data to the host 223.
　なお、ここではレーザダイオード302とレーザダイオード315を駆動するために同一のレーザドライバ301を用いたが、それぞれのレーザダイオードに固有のレーザドライバを備えても良い。また、球面収差補正素子309は、405nmの光学系および650nmの光学系の両方に影響する位置に配置されてもよく、たとえば1/4波長板310とダイクロイックミラー308の間に設置しても良い。 Although the same laser driver 301 is used here to drive the laser diode 302 and the laser diode 315, each laser diode may be provided with a laser driver specific to it. Further, the spherical aberration correction element 309 may be disposed at a position that affects both the 405 nm optical system and the 650 nm optical system, and may be disposed between the quarter wavelength plate 310 and the dichroic mirror 308, for example. .
　図２１に光ディスク記録再生装置221に光ディスク222を挿入時の光ディスク記録再生装置221の処理フローを示した。 FIG. 21 shows a processing flow of the optical disc recording / reproducing apparatus 221 when the optical disc 222 is inserted into the optical disc recording / reproducing apparatus 221.
　S401で光ディスク222を光ディスク記録再生装置221に挿入すると、S402で光ディスク記録再生装置221はディスクの有無の確認やディスク種別の確認を行う。このとき、たとえば光ディスク記録再生装置221は光ディスク222にレーザ光を照射して、反射光によって認識を行うことができる。 When the optical disc 222 is inserted into the optical disc recording / playback device 221 in S401, the optical disc recording / playback device 221 checks the presence / absence of a disc and the disc type in S402. At this time, for example, the optical disc recording / reproducing apparatus 221 can irradiate the optical disc 222 with laser light and perform recognition by reflected light.
　次にS403では、挿入された光ディスク222に対して、光ディスク記録再生装置221内の各種パラメータを好適するための調整処理を行う。各種パラメータとは、たとえばフォーカス制御手段212やトラッキング制御手段215内に含まれる増幅器の増幅率を光ディスク222の反射率にあわせて調節することなどが挙げられる。 Next, in S403, adjustment processing for making various parameters in the optical disc recording / reproducing apparatus 221 suitable is performed on the inserted optical disc 222. Examples of the various parameters include adjusting the amplification factor of the amplifier included in the focus control unit 212 and the tracking control unit 215 in accordance with the reflectance of the optical disc 222.
　各種調整を行った後、S404で光ディスク222の管理情報を読み出す。 After performing various adjustments, the management information of the optical disc 222 is read in S404.
　S405まで処理が進むと、記録または再生可能な状態となり、ホスト223からのコマンドに応じて記録または再生を行うことができる。 When the process proceeds to S405, recording or playback is possible, and recording or playback can be performed in accordance with a command from the host 223.
　調整処理S403のタイミングはこれに限るものではなく、一部の調整処理を管理情報読み出しS404の後などに行ってもよい。 The timing of the adjustment process S403 is not limited to this, and part of the adjustment process may be performed after the management information read S404.
　図２９に、前記記録または再生可能な状態となった光ディスク記録再生装置221に記録コマンドが送られた場合の処理フローを示した。
光ディスク記録再生装置221は、記録コマンドを受信する（Ｓ1201）と現在挿入されている光ディスク222に記録を行う場合にＯＰＣ処理が必要かを判定する（Ｓ1202）。
ＯＰＣ処理は例えば、光ディスク記録再生装置221に光ディスク222が挿入されて、最初の記録コマンド受信時等、挿入された光ディスク222に対して最適となる記録用のレーザ光強度が求まっていない場合に必要と判定される。
ＯＰＣ処理が必要と判定されると、後記するＯＰＣ処理を行い最適となる記録のレーザ光強度を求める(S1203)。
その後、記録を行う位置にレーザスポットLSw及びレーザスポットLSgを位置付けるシーク動作を行う(S1204)
その後、記録処理(S1205)を行う。
ここで、図２２を用いて記録処理(S1204)について説明を行う。 FIG. 29 shows a processing flow in the case where a recording command is sent to the optical disc recording / reproducing apparatus 221 in a state where recording or reproduction is possible.
When receiving the recording command (S1201), the optical disc recording / reproducing apparatus 221 determines whether or not the OPC process is necessary when recording on the optical disc 222 currently inserted (S1202).
The OPC processing is necessary when, for example, the optical disc 222 is inserted into the optical disc recording / reproducing apparatus 221 and the optimum laser beam intensity for recording is not obtained for the inserted optical disc 222, such as when the first recording command is received. It is determined.
If it is determined that the OPC process is necessary, an OPC process to be described later is performed to obtain an optimum recording laser beam intensity (S1203).
Thereafter, a seek operation is performed to position the laser spot LSW and the laser spot LSg at the recording position (S1204).
Thereafter, a recording process (S1205) is performed.
Here, the recording process (S1204) will be described with reference to FIG.
　図２２は、図２０に示した構造を有した光ディスク222の一部を切り出し、拡大したものである。 FIG. 22 is an enlarged view of a part of the optical disk 222 having the structure shown in FIG.
　図２２は、記録用の光スポット500が記録層に集光され、光ディスク222の接線方向に進みながらマークを記録している様子を示しており、同時に、トラッキングサーボ制御用の光スポット501と光スポット502が、光スポット500と光ディスク222と半径方向に一定の距離を置き、記録済みのマーク上と、後にマークが記録される予定の領域(未記録領域)にそれぞれ集光されおり、さらに、光スポット500の略直下のガイド層の溝(トラック)に、光スポット511が集光されていることを示している。なお、光スポット500、501、および502は、元は同じ光束から分離され、同一の対物レンズ311(図示せず)から放たれたものであり、図２０ではレーザスポットLSwとして記載されている。
光スポット511は、光スポット500、501、および502とは異なる光束であるが、それらと同じ対物レンズ311から放たれたことを示しており、図２０ではレーザスポットLSgとして記載されている。
光ディスク記録再生装置221は、記録層に記録済みのマークが存在する場合、光スポット501もしくは光スポット502が記録済みのマークを辿るようトラッキングを制御し、光スポット500のディスク半径方向の位置を確定し、光スポット500のレーザ光の強度を変化させマークを記録する。
また、光スポット511はガイド層のトラック上に位置付くように制御され、トラックのウォブルを読み出すことで、光スポット500と光ディスク222の相対速度を求めそれにより、記録するマークの長さを決定する。
記録動作(S1205)が終了すると記録動作終了(S1206)となる。
ＯＰＣ処理が不要と判定されるとシーク動作(S1204),記録動作(S1295)と続けて行われ、記録動作終了となる(S1206)。 FIG. 22 shows a state in which a recording light spot 500 is focused on the recording layer and a mark is recorded while proceeding in the tangential direction of the optical disk 222. At the same time, the tracking servo control light spot 501 and the light are recorded. A spot 502 is placed at a certain distance in the radial direction from the light spot 500 and the optical disc 222, and is focused on the recorded mark and on the area where the mark is to be recorded (unrecorded area). It shows that the light spot 511 is condensed in the groove (track) of the guide layer substantially directly below the light spot 500. The light spots 500, 501, and 502 are originally separated from the same light flux and emitted from the same objective lens 311 (not shown), and are described as laser spots LSW in FIG.
The light spot 511 is a light flux different from that of the light spots 500, 501, and 502, but indicates that the light spot 511 is emitted from the same objective lens 311, and is described as a laser spot LSg in FIG.
The optical disc recording / reproducing device 221 controls tracking so that the light spot 501 or the light spot 502 follows the recorded mark when a recorded mark exists in the recording layer, and determines the position of the light spot 500 in the disc radial direction. Then, the mark is recorded by changing the intensity of the laser beam of the light spot 500.
The light spot 511 is controlled so as to be positioned on the track of the guide layer, and by reading the wobble of the track, the relative speed between the light spot 500 and the optical disk 222 is obtained, thereby determining the length of the mark to be recorded. .
When the recording operation (S1205) ends, the recording operation ends (S1206).
If it is determined that the OPC process is unnecessary, the seek operation (S1204) and the recording operation (S1295) are performed, and the recording operation ends (S1206).
　（ＯＰＣ動作の説明）
次にOPCの動作について説明する。図２３にOPC動作のフローチャートの例を示す。まず、OPC動作が開始S1601されると、まず挿入された光ディスク222の指定の層に対するOPCが最初に行われたかをチェックS1602する。
このチェックは、例えば指定の層のOPC領域にレーザスポットLSwを移動させ、反射光から記録マーク列が検出されるかを識別すればよい。
指定の層に対する初回のOPCであった場合、初回OPCの位置に位置付けを行う（S1603）。この時、トラッキング制御手段215は、トラッキング誤差信号生成手段210からのトラッキング誤差信号を元にトラッキング駆動手段216を駆動する信号を出力し、対物レンズ311を動かす。
この時、トラッキング制御手段215はリレーレンズ駆動手段219へは駆動信号の出力は、出力しないもしくは、一定の信号を出力する。
リレーレンズ駆動手段219への入力が一定もしくは入力がない事でリレーレンズ321の半径方向は駆動されないもしくは、一定の位置に位置付けられている事となる。
その後、初回のOPCの動作S1604を行う。
OPCの動作は、例えばレーザ光の強度を変えながら試し記録を行い、その後試し記録を行った領域を再生し再生信号の振幅の変化と試し記録時のレーザ光の強度から最適となる記録のレーザ光強度を計算する事で最適となるレーザ光強度を求めている。
その後、先ほどのOPCで求めたレーザ光の強度でＯＰＣ領域にマーク列を記録S1605する。ここで、記録されるマーク列は、例えば図２４に示すように、記録マーク列とOPC用の未記録の部分を１周で交互となるパターンとする。
この時、トラッキング制御手段215は、トラッキング誤差信号生成手段210からのトラッキング誤差信号を元にトラッキング駆動手段216を駆動する信号を出力し、対物レンズ311を動かす。
この時、トラッキング制御手段215はリレーレンズ駆動手段219へは駆動信号の出力は、出力しないもしくは、一定の信号を出力する。
リレーレンズ駆動手段219への入力が一定もしくは入力がない事でリレーレンズ321の半径方向は駆動されないもしくは、一定の位置に位置付けられている事となる。
また、記録時の現在位置は、ガイド層に付加されているアドレス情報より取得する。
ここで、ＯＰＣ領域に最適なレーザ光強度で記録を行うパターン方法は、後記するようにトラッキング誤差信号を生成する光スポットを切り替える事でトラッキングサーボ制御が出来るように記録されていれば良い。 (Explanation of OPC operation)
Next, the operation of OPC will be described. FIG. 23 shows an example of a flowchart of the OPC operation. First, when the OPC operation is started S1601, firstly, it is checked whether or not the OPC for the specified layer of the inserted optical disk 222 has been performed first.
For this check, for example, the laser spot LSW may be moved to the OPC region of the designated layer to identify whether the recording mark row is detected from the reflected light.
If it is the first OPC for the specified layer, it is positioned at the position of the first OPC (S1603). At this time, the tracking control unit 215 outputs a signal for driving the tracking driving unit 216 based on the tracking error signal from the tracking error signal generating unit 210, and moves the objective lens 311.
At this time, the tracking control unit 215 does not output the driving signal to the relay lens driving unit 219 or outputs a constant signal.
Since the input to the relay lens driving means 219 is constant or not input, the radial direction of the relay lens 321 is not driven or is positioned at a fixed position.
Thereafter, the first OPC operation S1604 is performed.
The operation of the OPC is, for example, by performing test recording while changing the intensity of the laser beam, and then reproducing the area where the test recording has been performed, and the optimum recording laser based on the change in the amplitude of the reproduction signal and the intensity of the laser beam at the time of the test recording The optimum laser light intensity is obtained by calculating the light intensity.
Thereafter, a mark row is recorded S1605 in the OPC area with the intensity of the laser beam obtained by the previous OPC. Here, as shown in FIG. 24, for example, the mark row to be recorded has a pattern in which the recording mark row and the unrecorded portion for OPC alternate in one round.
At this time, the tracking control unit 215 outputs a signal for driving the tracking driving unit 216 based on the tracking error signal from the tracking error signal generating unit 210, and moves the objective lens 311.
At this time, the tracking control unit 215 does not output the driving signal to the relay lens driving unit 219 or outputs a constant signal.
Since the input to the relay lens driving means 219 is constant or not input, the radial direction of the relay lens 321 is not driven or is positioned at a fixed position.
The current position at the time of recording is acquired from address information added to the guide layer.
Here, the pattern method for performing recording with the optimum laser light intensity in the OPC area may be recorded so that tracking servo control can be performed by switching the light spot that generates the tracking error signal, as will be described later.
　例えば、記録を行う光スポット500に対して前後１トラックに光スポット501及び光スポット502を有する光ディスク記録再生装置221であれば、連続する３トラックにおいて、どの地点の３トラックを取り出しても最低１トラック分最適なレーザ光強度で記録されたマーク列があればＯＰＣ領域を安定したトラッキングサーボ制御が可能であり、記録用の光スポット500から光ディスク222の半径方向にそれぞれ距離が違うＮ個の光スポットを有する光ディスク222であれば、連続するＮトラックに最低１トラック分最適なレーザ光強度で記録されたマーク列があれば安定したトラッキングサーボ制御が可能である。 For example, in the case of the optical disc recording / reproducing apparatus 221 having the light spot 501 and the light spot 502 on one track before and after the light spot 500 to be recorded, at least 3 tracks at any point are extracted from 3 consecutive tracks. If there is a mark row recorded with an optimum laser beam intensity for the track, stable tracking servo control can be performed in the OPC area, and N light beams having different distances from the recording light spot 500 in the radial direction of the optical disk 222. In the case of the optical disk 222 having spots, stable tracking servo control is possible if there is a mark row recorded with an optimum laser beam intensity for at least one continuous N track.
　例えば、３つのスポットを有する光ディスク記録再生装置221であれば、３トラックに１トラック１周分マーク列の記録を行うとトラッキング誤差信号を生成する光スポットの切り替えをスピンドルモータ207からの回転同期信号でもタイミングを取ることが出来る。 For example, in the case of an optical disc recording / reproducing apparatus 221 having three spots, a rotation synchronization signal from the spindle motor 207 is used to switch a light spot that generates a tracking error signal when recording one mark per track for three tracks. But you can take the timing.
　例えば、最適なレーザ光強度でマーク列を生成しない未記録トラックの周方向の長さをOPCで使用する長さの整数倍とする事で、ＯＰＣの為の試し記録では使用出来ない領域全てをトラッキングサーボ制御用の記録マーク列として記録することが出来る。
これにより、トラッキング誤差信号を生成する光スポットを切り替えタイミング付近において切り替え前と後両方の光スポットから生成されるトラッキング誤差信号が略同一となる期間が長くなる為トラッキング誤差信号を生成する光スポットを切り替えが可能となる時間幅を増やす事が出来る。 For example, by setting the circumferential length of an unrecorded track that does not generate a mark row with the optimum laser light intensity to be an integral multiple of the length used in OPC, all areas that cannot be used in test recording for OPC It can be recorded as a record mark row for tracking servo control.
As a result, the light spot that generates the tracking error signal becomes longer since the tracking error signal generated from both the light spot before and after the switching is approximately the same in the vicinity of the switching timing. It is possible to increase the time width during which switching is possible.
　また、記録されるマーク列は、層情報や半径位置を示すアドレスを入れておく事で、OPC領域をトラッキングサーボ制御中の現在記録再生を行う光スポット500の位置を検出する事が出来る為良い。 In addition, the mark row to be recorded is good because it is possible to detect the position of the light spot 500 that is currently recording / reproducing during tracking servo control of the OPC area by entering layer information and an address indicating the radial position. .
　上記以外に層毎に、トラッキングサーボ制御を行う前に解析可能な例えば異なる長さのマークの繰り返しのマークパターンを記録する事でトラック制御を行う前に現在光スポット500の合焦している記録層を検出する事が出来る為良い。 In addition to the above, for each layer, it is possible to analyze before performing tracking servo control, for example, by recording a repetitive mark pattern of different length marks, the current light spot 500 is in focus before track control is performed. It is good because the layer can be detected.
　また、記録されるマーク列は、高密度に情報を記録する為ではなく、光スポット500を安定してトラッキングサーボ制御が出来るトラッキング誤差信号を生成する為に記録される為、実際の情報が記録される部分のマーク列とは異なり、トラッキング誤差信号の品質が安定するマーク列とすると、安定したトラッキングサーボ制御が可能となり良い。OPC領域にマーク列記録し終えるとOPC動作は終了となる（S1608）。
また、挿入された光ディスク222の指定の層に対するOPCが２回目以降であった場合、既にOPC領域に記録されている最適な記録用のレーザ光強度で記録されたマーク列を使用してトラッキングサーボ制御を行い、OPCに利用可能な領域を探索S1606する。 In addition, the recorded mark row is recorded not for recording information at a high density but for generating a tracking error signal that enables stable tracking servo control of the light spot 500, so that actual information is recorded. Unlike the mark row of the portion to be processed, if the mark row has a stable quality of the tracking error signal, stable tracking servo control may be possible. When the mark row is recorded in the OPC area, the OPC operation ends (S1608).
If the OPC for the specified layer of the inserted optical disk 222 is the second or later, the tracking servo is performed using the mark train recorded with the optimum recording laser light intensity already recorded in the OPC area. Control is performed, and an area usable for OPC is searched S1606.
　ここで、２回目以降のＯＰＣ処理時のＯＰＣ領域のトラッキングサーボ制御時のトラッキング誤差信号の生成方法を図１８を用いて説明する。 Here, a method for generating a tracking error signal during tracking servo control of the OPC area during the second and subsequent OPC processes will be described with reference to FIG.
　図１８は、光スポット500及び光スポット501及び光スポット502がＯＰＣ領域の記録マーク列上をトラッキングサーボ制御している最中の３つの時間を示した図である。時間は、(a),(b),(c)の順に進んでおり、光スポット500及び光スポット501及び光スポット502は図に向かって左から右に進んでいる。
ここで、(a)の場合には、光スポット500より生成したトラッキング誤差信号にてトラッキングサーボ制御を行う。
(b）の場合には、トラッキング誤差信号を生成する光スポットを光スポット500から光スポット501もしくは光スポット502に切り替えを行いトラッキングサーボ制御を行う。(C)の場合には、トラッキング誤差信号を生成する光スポットを光スポット501もしくは光スポット502から光スポット500に切り替えを行いトラッキングサーボ制御を行う。このように、トラッキング誤差信号を生成させる光スポットを、トラッキング誤差信号選択手段1104を用いて切り替えてトラッキングサーボ制御を行う事によってマーク列が記録されていない領域や最適となるレーザ光強度で記録されていない領域が存在するトラックに対しても安定したトラッキングサーボ制御を行いながら光スポット500の走査を行う事が出来る。
この時、トラッキング誤差信号選択手段1104の切り替え動作は、例えば記録されているマーク列から読み出された位置情報を元に切り替え動作を行うとよい。
もしくは、次に切り替える光スポットから得られるマーク列からの信号振幅が一定以上となった場合にトラッキング誤差信号を生成する光スポットを切り替えても良い。
また、後記に示すように一定のパターンにて記録を行った場合、そのパターンに合わせてトラッキング誤差信号を生成する光スポットを切り替えるようにすると、切り替えのタイミングを事前に把握する事が出来るため切り替えの処理を簡略化出来る為良い。 FIG. 18 is a diagram illustrating three times during which the light spot 500, the light spot 501, and the light spot 502 are performing tracking servo control on the recording mark row in the OPC area. Time advances in the order of (a), (b), and (c), and the light spot 500, the light spot 501, and the light spot 502 advance from left to right as viewed in the figure.
Here, in the case of (a), tracking servo control is performed using the tracking error signal generated from the light spot 500.
In the case of (b), the light spot that generates the tracking error signal is switched from the light spot 500 to the light spot 501 or the light spot 502, and tracking servo control is performed. In the case of (C), the light spot for generating the tracking error signal is switched from the light spot 501 or the light spot 502 to the light spot 500 to perform tracking servo control. In this way, the light spot that generates the tracking error signal is switched using the tracking error signal selection means 1104 and tracking servo control is performed, so that the mark row is not recorded or the laser light intensity is optimized. It is possible to scan the light spot 500 while performing stable tracking servo control even on a track where there is a non-existing region.
At this time, the switching operation of the tracking error signal selection means 1104 may be performed based on position information read from a recorded mark row, for example.
Alternatively, the light spot that generates the tracking error signal may be switched when the signal amplitude from the mark row obtained from the light spot to be switched next becomes a certain value or more.
In addition, when recording is performed in a certain pattern as shown later, switching the light spot that generates the tracking error signal according to the pattern enables switching timing so that the switching timing can be grasped in advance. This is good because the process can be simplified.
　その後、前記したように、トラッキング誤差信号を生成する光スポットの切り替え動作を行う事でトラッキングサーボ制御を行いながらOPC動作を行う（S1606）。
ここでの、OPC動作は初回OPC動作S1604に対して、トラッキング誤差信号を生成する光スポットを切り替えながらトラッキングサーボ制御をかけてOPCの動作を行っている点に特徴がある。
このように実際に記録を行う光スポット500とは別の光スポットにてトラッキングサーボ制御を行う事によって２回目以降のOPC動作を行う事によって、安定したトラッキングサーボ制御を行いながらOPC処理を行う事が出来る。 Thereafter, as described above, the OPC operation is performed while performing the tracking servo control by performing the switching operation of the light spot that generates the tracking error signal (S1606).
The OPC operation here is characterized in that the OPC operation is performed by applying tracking servo control to the first OPC operation S1604 while switching the light spot that generates the tracking error signal.
In this way, OPC processing is performed while performing stable tracking servo control by performing tracking servo control with a light spot different from the light spot 500 where recording is actually performed, and performing the second and subsequent OPC operations. I can do it.
　ここで、図２３のフローチャートでは、OPC領域にマーク列記録S1605をOPC記録直後に行っている。
これにより、初回OPC動作S1604時の光ディスク222と光ピックアップ203の半径方向の相対角度と同様の相対角度の状態でOPC領域にマーク列記録S1605する事が出来る。
また、光ディスク222の取出し等を行わなければ、光ディスク222と光ピックアップ203の半径方向の相対角度に変化が起きない安定した状態であれば、マーク列の記録動作は、光ディスク222の取り出し前までに行われていれば良く、例えば、図２５に示すフローチャートのようにOPCを行い、OPC領域へのマーク列の記録動作を、データの記録動作後に行うようにすると、データの記録までに必要な時間が短縮できる為良い。
以上のようにOPC動作を行う事によって、記録層とガイド層が分離している光ディスク222においても、安定したトラッキングサーボ制御を行いながらOPC動作を行う事が出来る。 Here, in the flowchart of FIG. 23, mark row recording S1605 is performed in the OPC area immediately after OPC recording.
As a result, the mark row recording S1605 can be performed in the OPC area at a relative angle similar to the relative angle between the optical disc 222 and the optical pickup 203 in the radial direction at the time of the first OPC operation S1604.
Further, if the optical disk 222 is not taken out or the like, and if the relative angle in the radial direction between the optical disk 222 and the optical pickup 203 does not change, the mark row recording operation is performed before the optical disk 222 is taken out. For example, if OPC is performed as in the flowchart shown in FIG. 25 and the mark string recording operation in the OPC area is performed after the data recording operation, the time required until the data recording is performed. Can be shortened.
By performing the OPC operation as described above, the OPC operation can be performed while performing stable tracking servo control even in the optical disc 222 in which the recording layer and the guide layer are separated.
　また、本実施例では、リレーレンズ321を光軸を変化させるように駆動させる事で、レーザスポットLSgとレーザスポットLSwの半径方向の相対位置を変化させると記載したが、例えば、ダイクロイックミラー308を回転させる事により、光ディスク222に集光するレーザスポットLSgとレーザスポットLSwの半径方向の相対位置を変化させてもよく、それ以外であっても、レーザスポットLSgとレーザスポットLSwの相対位置を半径方向に変化させる事が出来れば本実施例は実施可能である。 Further, in the present embodiment, it is described that the relative position in the radial direction between the laser spot LSg and the laser spot LSW is changed by driving the relay lens 321 so as to change the optical axis, but for example, the dichroic mirror 308 is provided. By rotating, the relative position in the radial direction between the laser spot LSg and the laser spot LSw focused on the optical disk 222 may be changed. In other cases, the relative position between the laser spot LSg and the laser spot LSw may be changed to a radius. If the direction can be changed, this embodiment can be implemented.
（光ディスクの形態）
本実施例の光ディスク222の形態は実施例１と同様の形態である。 (Optical disc form)
The form of the optical disk 222 of the present embodiment is the same as that of the first embodiment.
　（光ディスク記録再生装置の形態）
本実施例の光ディスク記録再生装置221の形態は実施例３と同様の形態である。
動作としては、OPCの処理において実施例３で説明した処理と差異がある。 (Configuration of optical disc recording / reproducing apparatus)
The form of the optical disc recording / reproducing apparatus 221 of the present embodiment is the same as that of the third embodiment.
As an operation, the OPC process is different from the process described in the third embodiment.
　（OPC動作の説明）
図２６を用いて本実施例のOPCの動作について説明する。
図２６にOPC動作のフローチャートの例を示す。
まず、OPC動作が開始される（S901）。そうすると、まず挿入された光ディスク222の指定の層に対するOPCが最初に行われたかをチェックする（S902）。
このチェックは、例えば指定の層のOPC領域にレーザスポットLSwを移動させ、反射光から記録マーク列が検出されるかを識別すればよい。
指定の層に対する初回のOPCであった場合、初回OPCの位置に位置付けを行う（S903）。
その後、初回のOPCの動作を行う（S904）。
OPCの動作は、実施例３で示している。
その後、OPCに使用した領域の上書き処理を行う（S905）。 (Explanation of OPC operation)
The operation of the OPC according to this embodiment will be described with reference to FIG.
FIG. 26 shows an example of a flowchart of the OPC operation.
First, the OPC operation is started (S901). Then, first, it is checked whether the OPC for the specified layer of the inserted optical disk 222 has been performed first (S902).
For this check, for example, the laser spot LSW may be moved to the OPC region of the designated layer to identify whether the recording mark row is detected from the reflected light.
If it is the first OPC for the specified layer, it is positioned at the position of the first OPC (S903).
Thereafter, the first OPC operation is performed (S904).
The operation of OPC is shown in the third embodiment.
Thereafter, the area used for OPC is overwritten (S905).
　この時、上書きを行うレーザ光の強度を図２７に示す。
OPCの動作は、レーザ光の強度を変化させて試し記録を行い、その後前記記録された領域を再生し、再生信号の振幅との試し記録時のレーザ光の強度による変化から最適となるレーザ光の強度を学習している。
その為、OPC後の領域は試し記録の為に最適なレーザ光の強度とは違った複数のレーザ光強度で記録されたマークが存在している。
上書き処理S905では、試し記録で記録されたマークがある領域に対して再度記録を行う事が出来るレーザ光の強度で記録を行う。 At this time, the intensity of the laser beam for overwriting is shown in FIG.
The operation of the OPC is performed by performing test recording by changing the intensity of the laser beam, and then reproducing the recorded area, and the optimum laser beam from the change due to the intensity of the laser beam at the time of trial recording with the amplitude of the reproduction signal Learning the intensity of.
Therefore, there are marks recorded with a plurality of laser light intensities different from the optimum laser light intensity for trial recording in the area after OPC.
In the overwriting process S905, recording is performed with the intensity of the laser beam that can be recorded again on the area having the mark recorded by the trial recording.
　ここで、再度記録を行う場合のレーザ光の強度は、上書き処理S905が行われた後の記録マーク列から生成されるトラッキング誤差信号が、最適な記録状態となるレーザ光強度で記録されたマーク列から生成されるトラッキング誤差信号と同等となるように記録されていれば良く、例えば、OPC処理にて記録された複数のレーザ光強度の平均の強度を求められた最適な記録となるレーザ光強度から引いたレーザ光強度で再度記録すると平均的に、最適な記録となるレーザ光強度で記録されたマーク列を生成する事が出来る為良い。 Here, the intensity of the laser beam when re-recording is the mark recorded with the laser beam intensity at which the tracking error signal generated from the record mark sequence after the overwrite process S905 is performed is in an optimum recording state. It is only necessary to be recorded so as to be equivalent to the tracking error signal generated from the column. For example, the laser beam that is the optimum recording for which the average intensity of a plurality of laser light intensities recorded by the OPC process is obtained. When recording is performed again with the intensity of the laser beam subtracted from the intensity, a mark row recorded with the laser beam intensity that is optimally recorded on average can be generated.
　また、例えば試し記録時のレーザ光の強度により記録時のレーザ光の強度を変化させる事で、記録後のマークが一定の信号振幅として再生されるよう変化させる事で、全体のマークの信号振幅を一定にする事が出来るため良い。
こうする事により、記録後にOPC領域に一定以上の振幅で記録されたマーク列を形成する事が出来るようになり、安定したトラッキングサーボ制御を行う事が出来るようになる。この時、上書きするマーク列のパターンは、OPC時に記録したマーク列と同一のマーク列とすると、OPCにて記録されたマーク列の信号振幅を上げることが出来る為良い。 Also, for example, by changing the intensity of the laser beam at the time of recording according to the intensity of the laser beam at the time of test recording, the signal amplitude of the entire mark can be changed by changing the recorded mark to be reproduced as a constant signal amplitude. It is good because it can be made constant.
By doing so, it becomes possible to form a mark row recorded with a certain amplitude or more in the OPC area after recording, and to perform stable tracking servo control. At this time, if the pattern of the mark row to be overwritten is the same as the mark row recorded at the time of OPC, the signal amplitude of the mark row recorded by OPC can be increased.
　以上のように記録を行う事で、OPCで使用した領域であっても、安定したマーク列を形成する事が出来る。
これにより、安定したトラッキングサーボ制御をOPC領域で実現する事が出来る。
また、実施例４の方式では、実施例１の方式のようにOPC領域にトラッキングサーボ制御用のマーク列を記録しない為、OPCに使用できる領域が増える為良い。 By performing recording as described above, a stable mark row can be formed even in an area used in OPC.
As a result, stable tracking servo control can be realized in the OPC region.
Further, in the method of the fourth embodiment, since the mark row for tracking servo control is not recorded in the OPC area unlike the method of the first embodiment, the area usable for OPC is preferably increased.
　また、上記実施例では複数の記録層を有する光ディスクを対象としたが、必ずしも記録層が複数あるような構造の光ディスクである必要は無く、例えば、体積記録されるような3次元記録層を有する光ディスクであっても良い。 In the above embodiment, an optical disk having a plurality of recording layers is targeted. However, the optical disk does not necessarily have a structure having a plurality of recording layers. For example, it has a three-dimensional recording layer for volume recording. It may be an optical disk.
　図３０は、本発明に従う光ディスク装置の一実施例を示すブロック構成図である。
  光ディスク装置は装置に装着された光ディスク３３１にレーザ光を照射することで情報の記録または再生を行い、SATA(Serial Advanced Technology Attachment)などのインターフェースを通じてPC(Personal Computer）などのホスト３３０と通信を行う。 FIG. 30 is a block diagram showing an embodiment of an optical disc apparatus according to the present invention.
The optical disk apparatus records or reproduces information by irradiating an optical disk 331 mounted on the apparatus with laser light, and communicates with a host 330 such as a PC (Personal Computer) through an interface such as SATA (Serial Advanced Technology Attachment). .
　(ディスク構造と光スポットの位置関係)
　図３１に、本実施例が対象とする光ディスクの構造(断面)を示す。同図の３３１は、溝が形成されたサーボ層を一つと、溝が無くフラットな記録層を一または複数有した光ディスクである。サーボ層の溝は、ＤＶＤやＢＤといったディスクに見られるような溝と同様に、ディスク回転軸を中心とした螺旋状の溝である。 (Relationship between disk structure and light spot)
FIG. 31 shows the structure (cross section) of an optical disc targeted by this embodiment. In the figure, reference numeral 331 denotes an optical disc having one servo layer with grooves and one or more flat recording layers without grooves. The groove of the servo layer is a spiral groove with the disk rotation axis as the center, similar to the groove found on a disk such as DVD or BD.
　また、同図の１２１１は、光ディスク３３１にレーザ光線を集光するため対物レンズである。同図は、対物レンズ１２１１を異なる２つの光束が通過し、一つの光束が、光ディスク３３１のサーボ層に集光され、もう一つの光束が、光ディスク３３１の複数ある記録層のうちの一つに集光されていることを示している。本発明が対象とする光ディスクは、このように２つ、あるいは、２つ以上の光束を用いて記録または再生を行う。 Also, reference numeral 1211 in the figure is an objective lens for condensing a laser beam on the optical disk 331. In the figure, two different light beams pass through the objective lens 1211, one light beam is condensed on the servo layer of the optical disk 331, and the other light beam is applied to one of a plurality of recording layers of the optical disk 331. It shows that it is condensed. As described above, the optical disk targeted by the present invention performs recording or reproduction using two or more light beams.
　図３２を用いてサーボ層に集光される光スポットと記録層に集光される光スポットの関係をより詳細に説明する。図３２は図３１に示した構造を有した光ディスクの一部を切り出し、拡大したものである。図３２において、光スポット３００は記録層に集光され、光ディスク３３１の接線方向に進みながらマークを記録している様子を示している。また、同時に、光スポット３０１と光スポット３０２が、光スポット３００と一定の距離を置き、記録済みのマーク上と、後にマークが記録される予定の領域(未記録領域)にそれぞれ集光されている。さらに、光スポット３００の略直下のサーボ層の溝(トラック)に光スポット３１１が集光されている。なお、光スポット３００、３０１、および３０２は、元は同じ光束から分離され、同一の対物レンズ１２１１から放たれたものであり、光スポット３１１は、光スポット３００、３０１、および３０２とは異なる光束であるが、それらと同じ対物レンズ１２１１から放たれたことを示している。 32, the relationship between the light spot focused on the servo layer and the light spot focused on the recording layer will be described in more detail. FIG. 32 is an enlarged view of a part of an optical disc having the structure shown in FIG. In FIG. 32, the light spot 300 is focused on the recording layer and shows a state in which marks are recorded while proceeding in the tangential direction of the optical disk 331. At the same time, the light spot 301 and the light spot 302 are focused at a certain distance from the light spot 300 on the recorded mark and on the area where the mark is to be recorded (unrecorded area). Yes. Further, the light spot 311 is collected in the groove (track) of the servo layer substantially immediately below the light spot 300. The light spots 300, 301, and 302 are originally separated from the same light flux and emitted from the same objective lens 1211, and the light spot 311 is different from the light spots 300, 301, and 302. However, it is shown that they were released from the same objective lens 1211 as those.
　光スポット３００、光スポット３０１、光スポット３０２の半径方向の間隔はトラックピッチ（例えば０．３２ｕｍ）に等しくなるように図３０のグレーティング３４１等の光学素子により調整する。ただし、周方向の距離はディテクタ１２１４にて分解できる距離であれば良い。ここで、光スポット３００、光スポット３０１、光スポット３０２の半径方向のトラックピッチの設計はグレーティング３４１や記録する密度等により変わるため０．３２ｕｍは一例として示している。また、本実施例ではレーザ光をグレーティング３４１により３ビームとしたが、記録層において記録マークに追従する方式であれば光スポット３００と光スポット３０１の２ビーム方式や複数の光ビーム（メインビーム０次光及びそのサーボビーム±１次光、そのサーボビーム±２次光）の５ビームのような複数の光ビームの方式も考えられる。 The distance between the light spot 300, the light spot 301, and the light spot 302 in the radial direction is adjusted by an optical element such as a grating 341 in FIG. However, the distance in the circumferential direction may be a distance that can be resolved by the detector 1214. Here, since the design of the track pitch in the radial direction of the light spot 300, the light spot 301, and the light spot 302 varies depending on the grating 341, the recording density, etc., 0.32um is shown as an example. In this embodiment, the laser beam is made up of three beams by the grating 341. However, the two-beam method of the light spot 300 and the light spot 301 or a plurality of light beams (main beam 0) can be used as long as the method follows the recording mark in the recording layer. A system of a plurality of light beams such as five beams of secondary light, servo beam ± primary light, servo beam ± secondary light) is also conceivable.
　また、記録時の光スポットの強度は、光スポット３００にて記録マークを形成しかつ光スポット３０１にて既に記録されている記録マークを上書きすることが無く、また光スポット３０２にて未記録部を記録することが無いように例えば光スポット３０１対光スポット３００対光スポット３０２の光の強度比を１：１０：１とする。スポットの強度比はこれに限るものではなく、光スポット３００にて記録マークを形成しかつ光スポット３０１にて既に記録されている記録マークを上書きすることが無く、また光スポット３０２にて未記録部を記録することが無ければどのような強度比としても良い。 Further, the intensity of the light spot at the time of recording does not form a recording mark at the light spot 300 and does not overwrite the recording mark already recorded at the light spot 301. For example, the light intensity ratio of the light spot 301 to the light spot 300 to the light spot 302 is set to 1: 10: 1. The intensity ratio of the spot is not limited to this. A recording mark is not formed on the light spot 300 and a recording mark already recorded on the light spot 301 is not overwritten. Any intensity ratio may be used as long as no part is recorded.
　(本実施例の光ディスク装置の構成)
　図３０の光ディスク装置は、光ピックアップ３３２と、信号処理回路３３３と、スピンドルモータ３３４と、サーボエラー信号生成回路３３５と、記録再生信号処理回路３３６と、スピンドル駆動回路３３７と、アクチュエータ駆動回路３３８と、リレーレンズ駆動回路３３９と、収差補正素子駆動回路３４０で構成される。 (Configuration of optical disc apparatus of this embodiment)
30 includes an optical pickup 332, a signal processing circuit 333, a spindle motor 334, a servo error signal generation circuit 335, a recording / reproduction signal processing circuit 336, a spindle driving circuit 337, and an actuator driving circuit 338. , A relay lens drive circuit 339 and an aberration correction element drive circuit 340.
　信号処理回路３３３は光ディスク装置の各種の信号処理を行う回路であり、電位Ｖｒｅｆを基準として動作する。この信号処理回路３３３は、システム制御回路２３０１と、記録層フォーカス制御回路２３０２と、スイッチ２３０３と、加算器２３０４と、記録層フォーカス駆動電圧生成回路２３０５と、サーボ層フォーカス制御回路２３０６と、スイッチ２３０７と、加算器２３０８と、サーボ層フォーカス駆動電圧生成回路２３０９と、サーボ層トラッキング制御回路２３１０と、スイッチ２３１１と、相対位置制御回路２３１２と、スイッチ２３１４と、スピンドル制御回路２３１３で構成される。 The signal processing circuit 333 is a circuit that performs various types of signal processing of the optical disk device, and operates with the potential Vref as a reference. The signal processing circuit 333 includes a system control circuit 2301, a recording layer focus control circuit 2302, a switch 2303, an adder 2304, a recording layer focus drive voltage generation circuit 2305, a servo layer focus control circuit 2306, and a switch 2307. An adder 2308, a servo layer focus drive voltage generation circuit 2309, a servo layer tracking control circuit 2310, a switch 2311, a relative position control circuit 2312, a switch 2314, and a spindle control circuit 2313.
　光ディスク３３１はスピンドルモータ３３４により、所定の回転数で回転される。スピンドルモータ３３４は、信号処理回路３３３に搭載されたシステム制御回路２３０１からの指令信号を受けたスピンドル制御回路２３１３によって制御される。スピンドル制御回路２３１３から出力された信号はスピンドル駆動回路３３７で増幅され、増幅された信号がスピンドルモータ３３４に供給される。 The optical disk 331 is rotated at a predetermined rotational speed by the spindle motor 334. The spindle motor 334 is controlled by a spindle control circuit 2313 that receives a command signal from a system control circuit 2301 mounted on the signal processing circuit 333. The signal output from the spindle control circuit 2313 is amplified by the spindle drive circuit 337, and the amplified signal is supplied to the spindle motor 334.
　光ピックアップ３３２は、たとえば４０５ｎｍと６５０ｎｍなど波長の異なる２つの光学系を備えている。 The optical pickup 332 includes two optical systems having different wavelengths such as 405 nm and 650 nm.
　まず、４０５ｎｍの光学系について説明する。レーザパワー制御回路１２０１は、システム制御回路２３０１によって制御されており、レーザダイオード１２０２を駆動する電流を出力する。この駆動電流は、レーザノイズを抑制するために数百ＭＨｚの高周波重畳が印加されている。レーザダイオード１２０２は、駆動電流に応じた波形で波長４０５ｎｍのレーザ光を出射する。出射されたレーザ光はコリメータレンズ１２０３にて平行光となり、ビームスプリッタ１２０４で一部が反射し、集光レンズ１２０５によってパワーモニタ１２０６に集光する。パワーモニタ１２０６は、レーザ光の強度に応じた電流または電圧をシステム制御回路２３０１にフィードバックする。これによって光ディスク３３１の記録層に集光するレーザ光の強度が、たとえば２ｍＷなど所望の値に保持される。一方、ビームスプリッタ１２０４を透過したレーザ光は３ビーム仕様のグレーティング３４１により、図３２に示した光スポット３００から３０２に対応する３つの光ビーム（メインビーム０次光及びそのサーボビーム±１次光）となり、偏光ビームスプリッタ１２０７にて反射し、収差補正素子駆動回路３４０にて駆動される収差補正素子１２０９によって収束・発散が制御され、ダイクロイックミラー１２０８を透過する。ここで、収差補正素子１２０９はシステム制御回路２３０１により収差補正素子駆動回路３４０を介して記録層に応じた所定の位置となるように制御が行われる。ダイクロイックミラー１２０８は特定の波長の光を反射し、その他の波長の光を透過する光学素子である。ここでは波長４０５ｎｍの光を透過し、６５０ｎｍの光を反射するものとする。ダイクロイックミラー１２０８を透過したレーザ光は、１／４波長板１２１０にて円偏光となり、対物レンズ１２１１によって光ディスク３３１の記録層に集光する。対物レンズ１２１１は、アクチュエータ１２１２によって位置制御される。光ディスク３３１によって反射したレーザ光は、光ディスク３３１に記録された情報に応じて強度が変調され、１／４波長板１２１０にて直線偏光となり、ダイクロイックミラー１２０８および収差補正素子１２０９を経て、偏光ビームスプリッタ１２０７を透過する。透過したレーザ光は、集光レンズ１２１３によってディテクタ１２１４に集光する。ディテクタ１２１４はレーザ光の強度を検出し、これに応じた信号をサーボエラー信号生成回路３３５及び記録再生信号処理回路３３６に対して出力する。 First, the 405 nm optical system will be described. The laser power control circuit 1201 is controlled by the system control circuit 2301 and outputs a current for driving the laser diode 1202. This driving current is applied with high frequency superposition of several hundred MHz in order to suppress laser noise. The laser diode 1202 emits laser light having a wavelength of 405 nm with a waveform corresponding to the drive current. The emitted laser light is converted into parallel light by the collimator lens 1203, partly reflected by the beam splitter 1204, and condensed on the power monitor 1206 by the condenser lens 1205. The power monitor 1206 feeds back a current or voltage corresponding to the intensity of the laser light to the system control circuit 2301. As a result, the intensity of the laser beam condensed on the recording layer of the optical disc 331 is maintained at a desired value such as 2 mW. On the other hand, the laser light transmitted through the beam splitter 1204 is divided into three light beams (main beam zero-order light and its servo beam ± primary light) corresponding to the light spots 300 to 302 shown in FIG. , And the convergence / divergence is controlled by the aberration correction element 1209 driven by the aberration correction element drive circuit 340 and transmitted through the dichroic mirror 1208. Here, the aberration correction element 1209 is controlled by the system control circuit 2301 through the aberration correction element drive circuit 340 so as to be at a predetermined position corresponding to the recording layer. The dichroic mirror 1208 is an optical element that reflects light of a specific wavelength and transmits light of other wavelengths. Here, it is assumed that light having a wavelength of 405 nm is transmitted and light having a wavelength of 650 nm is reflected. The laser beam that has passed through the dichroic mirror 1208 becomes circularly polarized light by the quarter-wave plate 1210 and is focused on the recording layer of the optical disc 331 by the objective lens 1211. The position of the objective lens 1211 is controlled by the actuator 1212. The intensity of the laser light reflected by the optical disk 331 is modulated according to the information recorded on the optical disk 331, becomes linearly polarized light by the quarter-wave plate 1210, passes through the dichroic mirror 1208 and the aberration correction element 1209, and then is polarized beam splitter. 1207 is transmitted. The transmitted laser light is condensed on the detector 1214 by the condenser lens 1213. The detector 1214 detects the intensity of the laser beam and outputs a signal corresponding to the intensity to the servo error signal generation circuit 335 and the recording / reproduction signal processing circuit 336.
　次に、６５０ｎｍの光学系について説明する。４０５ｎｍの光学系と同様に、レーザパワー制御回路１２０１がレーザダイオード１２１５を駆動し、レーザダイオード１２１５は波長６５０ｎｍのレーザ光を出射する。レーザ光の一部は、コリメータレンズ１２１６、ビームスプリッタ１２１７、集光レンズ１２１８を経て、パワーモニタ１２１９にてパワーがモニタされる。モニタしたパワーをシステム制御回路２３０１にフィードバックすることで、光ディスク３３１のサーボ層に集光するレーザ光の強度が、たとえば３ｍＷなど所望のパワーに保持される。ビームスプリッタ１２１７を透過したレーザ光は、偏光ビームスプリッタ１２２０を透過し、リレーレンズ１２２１に入射する。リレーレンズ１２２１はアクチュエータ１２２８により駆動され、サーボ層に照射される光スポットのフォーカス方向及びトラッキング方向の位置の制御が行われる。リレーレンズ１２２１を経たレーザ光は、ダイクロイックミラー１２０８にて反射し、１／４波長板１２１０を経て、対物レンズ１２１１により光ディスク１０１のサーボ層に集光する。光ディスク１０１にて反射したレーザ光を偏光ビームスプリッタ１２２０にて反射し、集光レンズ１２２２にてディテクタ１２２３に集光する。（実際のリレーレンズ１２２１は可動レンズと固定レンズからなり、ここでは可動レンズのみを図示している）ディテクタ１２２３はレーザ光の強度を検出し、これに応じた信号をサーボエラー信号生成回路３３５及び記録再生信号処理回路３３６に対して出力する。 Next, the 650 nm optical system will be described. Similar to the 405 nm optical system, the laser power control circuit 1201 drives the laser diode 1215, and the laser diode 1215 emits laser light having a wavelength of 650 nm. A part of the laser light passes through a collimator lens 1216, a beam splitter 1217, and a condenser lens 1218, and the power is monitored by a power monitor 1219. By feeding back the monitored power to the system control circuit 2301, the intensity of the laser beam condensed on the servo layer of the optical disc 331 is maintained at a desired power, such as 3 mW. The laser light that has passed through the beam splitter 1217 passes through the polarization beam splitter 1220 and enters the relay lens 1221. The relay lens 1221 is driven by an actuator 1228 to control the position of the light spot irradiated to the servo layer in the focus direction and the tracking direction. The laser light that has passed through the relay lens 1221 is reflected by the dichroic mirror 1208, passes through the quarter-wave plate 1210, and is condensed on the servo layer of the optical disc 101 by the objective lens 1211. The laser beam reflected by the optical disc 101 is reflected by the polarization beam splitter 1220 and condensed on the detector 1223 by the condenser lens 1222. (The actual relay lens 1221 is composed of a movable lens and a fixed lens, and only the movable lens is shown here). The detector 1223 detects the intensity of the laser beam, and outputs a signal corresponding to the servo error signal generation circuit 335 and The data is output to the recording / reproducing signal processing circuit 336.
　記録再生信号処理回路３３６では、ディテクタ１２１４で検出した信号に対して増幅、等化、復号などの処理を行い、光ディスク３３１の記録層から読み出した情報（記録されたデータや現在のアドレス情報など）をシステム制御回路２３０１に出力する。また、ディテクタ１２２３で検出した信号からサーボ層にウォブルして形成されたトラックに対応した信号により記録或いは再生を行う際の基準となるクロック信号を生成するとともに、光スポット３１１が追従しているサーボ層上の位置に対応したアドレスを再生してシステム制御回路２３０１に出力する。 In the recording / reproducing signal processing circuit 336, information read from the recording layer of the optical disc 331 (recorded data, current address information, etc.) is processed by performing processing such as amplification, equalization, and decoding on the signal detected by the detector 1214. Is output to the system control circuit 2301. In addition, a clock signal serving as a reference for recording or reproduction is generated from a signal detected by the detector 1223 by a signal corresponding to a track formed by wobbling the servo layer, and the servo that the light spot 311 follows is generated. The address corresponding to the position on the layer is reproduced and output to the system control circuit 2301.
　図３３にサーボエラー信号生成回路の構成を示す。ディテクタ１２２３から出力された信号はサーボ層フォーカスエラー信号生成回路１０５１及びサーボ層トラッキングエラー信号生成回路１０５２に入力される。サーボ層フォーカスエラー信号生成回路１０５１ではサーボ層に対するフォーカス制御に使用するためのサーボ層フォーカスエラー信号（以下、Ｓ＿ＦＥ）を生成し、サーボ層トラッキングエラー信号生成回路１０５２ではサーボ層のトラックからの光スポット３１１の位置ずれを表すサーボ層トラッキングエラー信号（以下、Ｓ＿ＴＥ）を生成して出力する。また、ディテクタ１２１４から出力された信号は記録層フォーカスエラー信号生成回路１０５３及び記録層トラッキングエラー信号生成回路１０５４に入力される。記録層フォーカスエラー信号生成回路１０５３では記録層に対するフォーカス制御に使用するための記録層フォーカスエラー信号（以下、Ｒ＿ＦＥ）を生成し、記録層トラッキングエラー信号生成回路１０５４では記録層の記録マーク列からなるトラックと光スポットとの位置ずれを表す記録層トラッキングエラー信号（以下、Ｒ＿ＴＥ）を生成して出力する。さらに、減算回路１０５５によりサーボ層トラッキングエラー信号Ｓ＿ＴＥと記録層トラッキングエラー信号Ｒ＿ＴＥとの差分が演算され、サーボ層上の光スポットと記録層上の光スポットのトラッキング方向の相対的な位置のずれを表す相対位置検出信号（以下、ＴＥ）が出力される。また、ディテクタ１２１４で検出した信号から光スポット３０２の総反射光量に対応するＦ＿ＳＵＭ信号を総光量検出回路１０５６で生成し、光スポット３０１の総反射光量に対応するＲ＿ＳＵＭ信号を総光量検出回路１０５７で生成して出力する。ここで、各エラー信号は、電位Ｖｒｅｆを基準として出力されるものとする。 Fig. 33 shows the configuration of the servo error signal generation circuit. The signal output from the detector 1223 is input to the servo layer focus error signal generation circuit 1051 and the servo layer tracking error signal generation circuit 1052. The servo layer focus error signal generation circuit 1051 generates a servo layer focus error signal (hereinafter referred to as S_FE) for use in focus control on the servo layer, and the servo layer tracking error signal generation circuit 1052 generates a light spot from the servo layer track. A servo layer tracking error signal (hereinafter referred to as S_TE) representing the 311 position deviation is generated and output. The signal output from the detector 1214 is input to the recording layer focus error signal generation circuit 1053 and the recording layer tracking error signal generation circuit 1054. The recording layer focus error signal generation circuit 1053 generates a recording layer focus error signal (hereinafter referred to as R_FE) for use in focus control for the recording layer, and the recording layer tracking error signal generation circuit 1054 includes a recording mark row of the recording layer. A recording layer tracking error signal (hereinafter referred to as R_TE) representing the positional deviation between the track and the light spot is generated and output. Further, the difference between the servo layer tracking error signal S_TE and the recording layer tracking error signal R_TE is calculated by the subtracting circuit 1055, and the relative position shift in the tracking direction between the light spot on the servo layer and the light spot on the recording layer is calculated. A relative position detection signal (hereinafter referred to as TE) is output. Further, an F_SUM signal corresponding to the total reflected light amount of the light spot 302 is generated from the signal detected by the detector 1214 by the total light amount detection circuit 1056, and an R_SUM signal corresponding to the total reflected light amount of the light spot 301 is generated by the total light amount detection circuit 1057. Generate and output. Here, each error signal is output with reference to the potential Vref.
　４０５ｎｍの光学系において記録層（記録層のうちのいずれか１つの層）に対して行われるフォーカス制御及びトラッキング制御について説明する。 Focus control and tracking control performed on the recording layer (any one of the recording layers) in the 405 nm optical system will be described.
　記録層フォーカス制御回路２３０２は、システム制御回路２３０１からの指令信号により、記録層フォーカスエラー信号Ｒ＿ＦＥに対してゲインと位相の補償を行い、記録層に対するフォーカス制御を行うための駆動信号を出力する。記録層フォーカス制御回路２３０２から出力された駆動信号は、スイッチ２３０３、加算器２３０４を介してアクチュエータ駆動回路３３８に入力される。 The recording layer focus control circuit 2302 performs gain and phase compensation for the recording layer focus error signal R_FE in response to a command signal from the system control circuit 2301, and outputs a drive signal for performing focus control on the recording layer. The drive signal output from the recording layer focus control circuit 2302 is input to the actuator drive circuit 338 via the switch 2303 and the adder 2304.
　スイッチ２３０３はシステム制御回路２３０１の出力するＲ＿ＦＯＮ信号に基づき、記録層フォーカス制御回路２３０２の出力信号もしくは基準電位Ｖｒｅｆを選択して出力する。Ｒ＿ＦＯＮ信号としてＨｉｇｈレベルが入力されると、スイッチ２３０３の端子はａが選択され、記録層フォーカス制御回路２３０２の出力信号が加算器２３０４を介してアクチュエータ駆動回路３３８に出力される。一方でＲ＿ＦＯＮ信号としてＬｏｗレベルが入力されると、スイッチ２３０３は端子ｂを選択し、基準電位Ｖｒｅｆを出力する。 The switch 2303 selects and outputs the output signal of the recording layer focus control circuit 2302 or the reference potential Vref based on the R_FON signal output from the system control circuit 2301. When a high level is input as the R_FON signal, a is selected as the terminal of the switch 2303, and the output signal of the recording layer focus control circuit 2302 is output to the actuator drive circuit 338 via the adder 2304. On the other hand, when the Low level is input as the R_FON signal, the switch 2303 selects the terminal b and outputs the reference potential Vref.
　この結果、Ｒ＿ＦＯＮ信号は記録層に対するフォーカス制御のオン・オフを指示する信号となる。またスイッチ２３０３は記録層に対するフォーカス制御のオン、オフを切り替えるスイッチとして機能する。Ｒ＿ＦＯＮ信号がＬｏｗからＨｉｇｈに切り替わることで記録層に対するフォーカス制御がオンになる。この動作はフォーカス引き込み動作と呼ばれる。 As a result, the R_FON signal is a signal for instructing on / off of focus control for the recording layer. A switch 2303 functions as a switch for switching on and off the focus control for the recording layer. When the R_FON signal is switched from Low to High, the focus control for the recording layer is turned on. This operation is called a focus pull-in operation.
　記録層フォーカス駆動電圧生成回路２３０５は、システム制御回路２３０１からの指令信号により、所定の電圧を出力する。記録層フォーカス駆動電圧生成回路２３０５は例えば、フォーカススイープ動作におけるスイープ電圧や、フォーカスジャンプ時のジャンプ電圧を出力する。 The recording layer focus drive voltage generation circuit 2305 outputs a predetermined voltage in response to a command signal from the system control circuit 2301. The recording layer focus drive voltage generation circuit 2305 outputs, for example, a sweep voltage in a focus sweep operation and a jump voltage at the time of a focus jump.
　記録層フォーカス駆動電圧生成回路２３０５の出力信号とスイッチ２３０３の出力信号を加算器２３０４により加算しＲ＿ＦＯＤとしてアクチュエータ駆動回路３３８に出力する。 The output signal of the recording layer focus drive voltage generation circuit 2305 and the output signal of the switch 2303 are added by the adder 2304 and output to the actuator drive circuit 338 as R_FOD.
　Ｒ＿ＦＯＤ信号に従ってアクチュエータ１２１２をディスク面に垂直な方向に駆動することで、対物レンズ１２１１がフォーカス方向に駆動される。これにより、記録層に光スポット３００が記録層で合焦するように記録層フォーカス制御が行われる。
次に、本実施例における記録層のトラッキング制御について説明する。 By driving the actuator 1212 in a direction perpendicular to the disk surface in accordance with the R_FOD signal, the objective lens 1211 is driven in the focus direction. Thereby, the recording layer focus control is performed so that the light spot 300 is focused on the recording layer.
Next, the tracking control of the recording layer in this embodiment will be described.
　トラッキング制御回路２３１０にはサーボエラー信号生成回路３３５からサーボ層トラッキングエラー信号Ｓ＿ＴＥと記録層トラッキングエラー信号Ｒ＿ＴＥが入力される。記録層に記録された情報を再生する場合には記録層に記録されたマーク列からなるトラックから検出した記録層トラッキングエラー信号Ｒ＿ＴＥに基づいてトラッキング制御を行う。このため、システム制御回路２３０１からの指令信号により、記録層トラッキングエラー信号Ｒ＿ＴＥに対してゲインと位相の補償を行い、トラッキング制御を行うための駆動信号を出力する。トラッキング制御回路２３１０から出力された駆動信号は、スイッチ２３１１を介してアクチュエータ駆動回路３３８に入力される。 Servo layer tracking error signal S_TE and recording layer tracking error signal R_TE are input to tracking control circuit 2310 from servo error signal generation circuit 335. When reproducing the information recorded on the recording layer, tracking control is performed based on the recording layer tracking error signal R_TE detected from the track formed of the mark row recorded on the recording layer. Therefore, the recording layer tracking error signal R_TE is compensated for gain and phase by a command signal from the system control circuit 2301, and a driving signal for performing tracking control is output. The drive signal output from the tracking control circuit 2310 is input to the actuator drive circuit 338 via the switch 2311.
　スイッチ１３１１はシステム制御回路２３０１の出力するＴＲＯＮ信号に基づき、トラッキング制御回路２３１０の出力信号もしくは基準電位Ｖｒｅｆを選択して、トラッキング駆動信号ＴＲＤとしてアクチュエータ駆動回路３３８に出力する。ＴＲＯＮ信号としてＨｉｇｈレベルが入力されると、スイッチ１３１１の端子はｅが選択され、トラッキング制御回路２３１０の出力信号がアクチュエータ駆動回路３３８に出力される。一方でＴＲＯＮ信号としてＬｏｗレベルが入力されると、スイッチ２３１１は端子ｆを選択し、基準電位Ｖｒｅｆを出力する。 The switch 1311 selects the output signal of the tracking control circuit 2310 or the reference potential Vref based on the TRON signal output from the system control circuit 2301, and outputs it to the actuator drive circuit 338 as the tracking drive signal TRD. When a high level is input as the TRON signal, e is selected as the terminal of the switch 1311, and an output signal of the tracking control circuit 2310 is output to the actuator drive circuit 338. On the other hand, when the Low level is input as the TRON signal, the switch 2311 selects the terminal f and outputs the reference potential Vref.
　この結果、ＴＲＯＮ信号はトラッキング制御のオン・オフを指示する信号となる。またスイッチ２３１１は、トラッキング制御のオン、オフを切り替えるスイッチとして機能する。ＴＲＯＮ信号がＬｏｗからＨｉｇｈに切り替わることでトラッキング制御がオンされることになり、この動作はトラック引き込み動作と呼ばれる。 As a result, the TRON signal is a signal for instructing on / off of the tracking control. The switch 2311 functions as a switch for switching tracking control on and off. Tracking control is turned on when the TRON signal is switched from Low to High, and this operation is called a track pull-in operation.
　トラッキング制御がオンし、トラック引き込み動作が行われると、アクチュエータ駆動手段３３８はトラッキング制御回路２３１０の出力信号に応じてアクチュエータ１２１２を駆動することで記録層に記録されたマーク列からなるトラックを光スポット３００が追従するようにトラッキング制御が行われる。 When the tracking control is turned on and the track pull-in operation is performed, the actuator driving unit 338 drives the actuator 1212 in accordance with the output signal of the tracking control circuit 2310, so that the track formed of the mark row recorded on the recording layer is the light spot. Tracking control is performed so that 300 follows.
　６５０ｎｍの光学系において、サーボ層に対して行われるフォーカス制御及びトラッキング制御について説明する。 Focus control and tracking control performed on the servo layer in the 650 nm optical system will be described.
　サーボ層フォーカス制御回路２３０６は、システム制御回路２３０１からの指令信号によりサーボ層フォーカスエラー信号Ｓ＿ＦＥに対してゲインと位相の補償を行い、サーボ層に対するフォーカス制御を行うための駆動信号を出力し、スイッチ２３０７、加算器２３０８を介してリレーレンズレンズ駆動回路３３９に入力される。これによりサーボ層に対するフォーカス制御が行われる。 The servo layer focus control circuit 2306 compensates the servo layer focus error signal S_FE for gain and phase in response to a command signal from the system control circuit 2301, outputs a drive signal for performing focus control on the servo layer, and switches 2307, and input to the relay lens lens driving circuit 339 via the adder 2308. Thereby, the focus control for the servo layer is performed.
　スイッチ２３０７はシステム制御回路２３０１の出力するＳ＿ＦＯＮ信号に基づき、サーボ層フォーカス制御回路２３０６の出力信号もしくは基準電位Ｖｒｅｆを選択して出力する。Ｓ＿ＦＯＮ信号としてＨｉｇｈレベルが入力されると、スイッチ２３０７の端子はｃが選択される。一方でＲ＿ＦＯＮ信号としてＬｏｗレベルが入力されると、スイッチ２３０７は端子ｄを選択し、基準電位Ｖｒｅｆを出力する。 The switch 2307 selects and outputs the output signal of the servo layer focus control circuit 2306 or the reference potential Vref based on the S_FON signal output from the system control circuit 2301. When a high level is input as the S_FON signal, c is selected as the terminal of the switch 2307. On the other hand, when the Low level is input as the R_FON signal, the switch 2307 selects the terminal d and outputs the reference potential Vref.
　この結果、Ｓ＿ＦＯＮ信号はサーボ層に対するフォーカス制御のオン・オフを指示する信号となる。またスイッチ２３０７は、サーボ層に対するフォーカス制御のオン、オフを切り替えるスイッチとして機能する。Ｓ＿ＦＯＮ信号がＬｏｗからＨｉｇｈに切り替わることでサーボ層に対するフォーカス制御がオンされることになり、この動作はフォーカス引き込み動作と呼ばれる。 As a result, the S_FON signal is a signal for instructing on / off of focus control for the servo layer. The switch 2307 functions as a switch for switching on / off the focus control for the servo layer. When the S_FON signal is switched from Low to High, the focus control for the servo layer is turned on, and this operation is called a focus pull-in operation.
　サーボ層フォーカス駆動電圧生成回路２３０９は、システム制御回路２３０１からの指令信号により、所定の電圧を出力する。サーボ層フォーカス駆動電圧生成回路２３０９は例えば、フォーカススイープ動作におけるスイープ電圧を出力する。 The servo layer focus drive voltage generation circuit 2309 outputs a predetermined voltage in response to a command signal from the system control circuit 2301. For example, the servo layer focus drive voltage generation circuit 2309 outputs a sweep voltage in the focus sweep operation.
　サーボ層フォーカス駆動電圧生成回路２３０９の出力信号とスイッチ２３０７の出力信号を加算器２３０８により加算しＳ＿ＦＯＤとしてリレーレンズ駆動回路３３９に出力する。 The output signal of the servo layer focus drive voltage generation circuit 2309 and the output signal of the switch 2307 are added by the adder 2308 and output to the relay lens drive circuit 339 as S_FOD.
　リレーレンズ駆動回路３３９は、Ｓ＿ＦＯＤ信号に従って光ピックアップ３３２内に搭載されたアクチュエータ１２２８を駆動する。この駆動により光ディスク３３１に照射された波長６５０ｎｍの光スポットが、常に光ディスク３３１のサーボ層の面上で合焦するようにサーボ層に対するフォーカス制御が行われる。 The relay lens driving circuit 339 drives the actuator 1228 mounted in the optical pickup 332 according to the S_FOD signal. The focus control on the servo layer is performed so that the light spot with a wavelength of 650 nm irradiated on the optical disc 331 by this driving is always focused on the surface of the servo layer of the optical disc 331.
　次に、本実施例におけるサーボ層のトラッキング制御について説明する。 Next, servo layer tracking control in this embodiment will be described.
　記録層に情報が記録されていない場合には、記録層に記録されたマーク列からなるトラックからトラッキングエラー信号を検出できないため、サーボ層に形成されたトラックから得られるサーボ層トラッキングエラー信号Ｓ＿ＴＥに基づいてトラッキング制御を行う。このため、システム制御回路２３０１からの指令信号により、サーボエラー信号生成回路３３５から入力されたサーボ層トラッキングエラー信号Ｓ＿ＴＥに対してゲインと位相の補償を行い、トラッキング制御を行うための駆動信号を出力する。トラッキング制御回路２３１０から出力された駆動信号は、スイッチ２３１１を介してアクチュエータ駆動回路３３８に入力される。 When no information is recorded on the recording layer, the tracking error signal cannot be detected from the track formed of the mark row recorded on the recording layer, so that the servo layer tracking error signal S_TE obtained from the track formed on the servo layer is detected. Based on the tracking control. Therefore, in response to a command signal from the system control circuit 2301, gain and phase compensation is performed on the servo layer tracking error signal S_TE input from the servo error signal generation circuit 335, and a drive signal for performing tracking control is output. To do. The drive signal output from the tracking control circuit 2310 is input to the actuator drive circuit 338 via the switch 2311.
　スイッチ２３１１はシステム制御回路２３０１の出力するＴＲＯＮ信号に基づき、トラッキング制御回路２３１０の出力信号もしくは基準電位Ｖｒｅｆを選択して、トラッキング駆動信号Ｓ＿ＴＲＤとしてアクチュエータ駆動回路１０８に出力する。ＴＲＯＮ信号としてＨｉｇｈレベルが入力されると、スイッチ２３１１の端子はｅが選択され、トラッキング制御回路２３１０の出力信号がアクチュエータ駆動回路３３８に出力される。一方でＴＲＯＮ信号としてＬｏｗレベルが入力されると、スイッチ２３１１は端子ｆを選択し、基準電位Ｖｒｅｆを出力する。 The switch 2311 selects the output signal of the tracking control circuit 2310 or the reference potential Vref based on the TRON signal output from the system control circuit 2301, and outputs it to the actuator drive circuit 108 as the tracking drive signal S_TRD. When the high level is input as the TRON signal, e is selected as the terminal of the switch 2311, and the output signal of the tracking control circuit 2310 is output to the actuator drive circuit 338. On the other hand, when the Low level is input as the TRON signal, the switch 2311 selects the terminal f and outputs the reference potential Vref.
　トラッキング制御がオンし、トラック引き込み動作が行われると、アクチュエータ駆動回路３３８はトラッキング制御回路２３１０の出力信号に応じてアクチュエータ１２１２を駆動することでサーボ層のトラックを光スポット３１１が追従するようにトラッキング制御が行われる　
　次に、本実施例における相対位置制御について説明する。この相対位置制御のための信号となる相対位置検出信号ＴＥの生成方法について説明する。情報の記録時において、一定のトラックピッチ間隔で記録マーク列を記録するには、波長４０５ｎｍの光スポットと波長６５０ｎｍの光スポットの光軸の相対関係を保持する制御が必要である。そこで、この異なる２つの波長の光軸の相対関係を制御するためには、波長６５０ｎｍの光スポット３１１の位置と波長４０５ｎｍの光スポット３０１の相対関係を一定に保つような制御が必要となる。これ以降では、サーボ層のトラックからの光スポット３１１位置ずれを表すサーボ層トラッキングエラー信号Ｓ＿ＴＥとし、記録層の記録マーク列からなるトラックからの光スポット３０１の位置ずれを表す記録層トラッキングエラー信号Ｒ＿ＴＥとする。サーボ層トラッキングエラー信号Ｓ＿ＴＥ、記録層トラッキングエラー信号Ｒ＿ＴＥ及びその差分である相対位置検出信号ＴＥをサーボエラー信号生成回路３３５にて生成する。ここで、サーボ層トラッキングエラー信号Ｓ＿ＴＥはサーボ層のトラックに追従しているときの信号であるため光軸の基準軸とする。この基準軸からの誤差はディスクのチルト等により生じるため、この基準軸からの誤差をリレーレンズ１２２１のアクチュエータ１２２８への制御の入力とすることで、２つの光軸の相対関係を保持することができるため記録済みの領域に上書き記録することを抑制することが可能となる。 When the tracking control is turned on and the track pull-in operation is performed, the actuator driving circuit 338 drives the actuator 1212 according to the output signal of the tracking control circuit 2310 so that the light spot 311 follows the track of the servo layer. Control is done
Next, the relative position control in the present embodiment will be described. A method for generating the relative position detection signal TE which is a signal for the relative position control will be described. In recording information, in order to record a record mark row at a constant track pitch interval, it is necessary to control to maintain the relative relationship between the optical spots of the light spot having a wavelength of 405 nm and the light spot having a wavelength of 650 nm. Therefore, in order to control the relative relationship between the optical axes of the two different wavelengths, it is necessary to control the relative relationship between the position of the light spot 311 having the wavelength of 650 nm and the light spot 301 having the wavelength of 405 nm. Thereafter, the servo layer tracking error signal S_TE representing the positional deviation of the light spot 311 from the track of the servo layer is used, and the recording layer tracking error signal R_TE representing the positional deviation of the light spot 301 from the track formed of the recording mark row of the recording layer. And A servo layer tracking error signal S_TE, a recording layer tracking error signal R_TE, and a relative position detection signal TE that is the difference between the servo layer tracking error signal S_TE and a servo error signal generation circuit 335 are generated. Here, since the servo layer tracking error signal S_TE is a signal when following the track of the servo layer, it is used as the reference axis of the optical axis. Since the error from the reference axis is caused by the tilt of the disk, etc., the relative relationship between the two optical axes can be maintained by using the error from the reference axis as the control input to the actuator 1228 of the relay lens 1221. Therefore, it is possible to suppress overwriting in the recorded area.
　相対位置制御回路２３１２は、システム制御回路２３０１からの指令信号により、相対位置検出信号ＴＥに対してゲインと位相の補償を行い、相対位置制御を行うための信号を出力する。相対位置制御回路２３１２から出力された信号は、スイッチ２３１４を介してリレーレンズ駆動回路３３９に入力される。 The relative position control circuit 2312 performs gain and phase compensation on the relative position detection signal TE in response to a command signal from the system control circuit 2301, and outputs a signal for performing relative position control. A signal output from the relative position control circuit 2312 is input to the relay lens driving circuit 339 via the switch 2314.
　スイッチ２３１４はシステム制御回路２３０１の出力するＴＬＯＮ信号に基づき、相対位置制御回路２３１２の出力信号もしくは基準電位Ｖｒｅｆを選択し、相対位置制御駆動信号ＴＬＤとしてリレーレンズ駆動回路３３９の入力となる。ＴＬＯＮ信号としてＨｉｇｈレベルが入力されると、スイッチ１３１４の端子はｇが選択され、相対位置検出回路２３１２の出力信号がリレーレンズ駆動回路３３９の入力となる。一方でＴＬＯＮ信号としてＬｏｗレベルが入力されると、スイッチ２３１４は端子ｈを選択し、基準電位Ｖｒｅｆを出力する。 The switch 2314 selects the output signal of the relative position control circuit 2312 or the reference potential Vref based on the TLON signal output from the system control circuit 2301, and becomes an input of the relay lens drive circuit 339 as the relative position control drive signal TLD. When the high level is input as the TLON signal, g is selected as the terminal of the switch 1314, and the output signal of the relative position detection circuit 2312 becomes the input of the relay lens driving circuit 339. On the other hand, when the Low level is input as the TLON signal, the switch 2314 selects the terminal h and outputs the reference potential Vref.
　この結果、ＴＬＯＮ信号は記録層に対する相対位置制御のオン・オフを指示する信号となる。またスイッチ２３１４は、記録層に対する相対位置制御のオン、オフを切り替えるスイッチとして機能する。ＴＬＯＮ信号がＬｏｗからＨｉｇｈに切り替わることで相対位置制御がオンされることになる。 As a result, the TLON signal is a signal for instructing on / off of relative position control with respect to the recording layer. The switch 2314 functions as a switch for switching on / off the relative position control with respect to the recording layer. The relative position control is turned on when the TLON signal is switched from Low to High.
　相対位置制御がオンし、リレーレンズ駆動回路３３９によりリレーレンズ１２２１をアクチュエータ１２２８により駆動すると、６５０ｎｍの光軸が相対位置制御駆動信号ＴＬＤに従って変化する。これにより、サーボ層に照射された光スポット３１１がトラック方向に変位し、サーボ層トラッキングエラー信号Ｓ＿ＴＥが変化する。このサーボ層トラッキングエラー信号Ｓ＿ＴＥの変化に対して、サーボ層トラッキング制御系により対物レンズ１２１１のアクチュエータ１２１２を駆動し、光スポット３１１がサーボ層のトラックを追従するように動作する。従って、相対位置制御による光スポット３１１のトラック方向へずれを抑制するためにはサーボ層トラッキング制御系の制御帯域よりも相対位置制御系の制御帯域が低くなるようにする必要がある。このため、例えば低域通過フィルタで相対位置検出信号ＴＥの周波数帯域制限を行う、或いはリレーレンズ１２２１のアクチュエータ１２２８の周波数応答特性を対物レンズ１２１１のアクチュエータ１２１２の周波数応答特性より低くしても良い。これにより、サーボ層に照射される６５０ｎｍの光スポットの位置と記録層に照射される４０５ｎｍの光スポットのトラック方向の相対位置が保持されるとともに、サーボ層のトラックを光スポット３１１が追従するように制御が行われる。 When the relative position control is turned on and the relay lens 1221 is driven by the actuator 1228 by the relay lens driving circuit 339, the optical axis of 650 nm changes according to the relative position control driving signal TLD. Thereby, the light spot 311 irradiated to the servo layer is displaced in the track direction, and the servo layer tracking error signal S_TE changes. In response to the change in the servo layer tracking error signal S_TE, the servo layer tracking control system drives the actuator 1212 of the objective lens 1211 so that the light spot 311 follows the track of the servo layer. Therefore, in order to suppress the deviation of the light spot 311 in the track direction due to the relative position control, it is necessary to make the control band of the relative position control system lower than the control band of the servo layer tracking control system. For this reason, for example, the frequency band limitation of the relative position detection signal TE may be performed using a low-pass filter, or the frequency response characteristic of the actuator 1228 of the relay lens 1221 may be made lower than the frequency response characteristic of the actuator 1212 of the objective lens 1211. Thereby, the relative position in the track direction of the 650 nm light spot irradiated to the servo layer and the 405 nm light spot irradiated to the recording layer is maintained, and the light spot 311 follows the track of the servo layer. Control is performed.
　図３４は相対位置検出信号ＴＥの概念図である。ここでは、一例としてサーボ層トラッキングエラー信号Ｓ＿ＴＥ、記録層トラッキングエラー信号Ｒ＿ＴＥの周波数、振幅は同様である場合を図示している。また、同図に示したようにサーボ層トラッキングエラー信号Ｓ＿ＴＥ、記録層トラッキングエラー信号Ｒ＿ＴＥ、相対位置検出信号ＴＥの正側を内周方向、負側を外周方向とする。図３４（ａ）は、記録層トラッキングエラー信号Ｒ＿ＴＥが基準電圧のＶｒｅｆからＶａのオフセットが生じた場合を図示している。この図では記録層トラッキングエラー信号Ｒ＿ＴＥはマーク列の中心から光スポット３０１がずれて位置づいていることを表している。従って、相対位置制御をしない場合には光スポット３００もＶａに相当する位置で記録することになる。これを防ぐために、相対位置検出信号ＴＥを生成し、Ｖａに相当するオフセットをキャンセルするようにリレーレンズ１２２１のアクチュエータ１２２８を制御する。この場合には、内周方向にオフセットしているため、リレーレンズ１２２１をアクチュエータ１２２８により外周方向にＶａだけ駆動する。これによりオフセットをキャンセルする。これにより、図３４（ｂ）に示すように、サーボ層トラッキングエラー信号Ｓ＿ＴＥ、記録層トラッキングエラー信号Ｒ＿ＴＥともに基準電圧のＶｒｅｆ近傍で動作し、サーボ層のサーボ溝および記録層のマーク列の中心に追従している状態にすることができる。 FIG. 34 is a conceptual diagram of the relative position detection signal TE. Here, as an example, a case where the servo layer tracking error signal S_TE and the recording layer tracking error signal R_TE have the same frequency and amplitude is illustrated. Further, as shown in the figure, the positive side of the servo layer tracking error signal S_TE, the recording layer tracking error signal R_TE, and the relative position detection signal TE is the inner circumferential direction, and the negative side is the outer circumferential direction. FIG. 34A illustrates a case where the recording layer tracking error signal R_TE has an offset of Va from the reference voltage Vref. In this figure, the recording layer tracking error signal R_TE indicates that the light spot 301 is displaced from the center of the mark row. Therefore, when the relative position control is not performed, the light spot 300 is also recorded at a position corresponding to Va. In order to prevent this, the relative position detection signal TE is generated, and the actuator 1228 of the relay lens 1221 is controlled so as to cancel the offset corresponding to Va. In this case, since the offset is in the inner circumferential direction, the relay lens 1221 is driven by Va in the outer circumferential direction by the actuator 1228. This cancels the offset. As a result, as shown in FIG. 34B, both the servo layer tracking error signal S_TE and the recording layer tracking error signal R_TE operate near the reference voltage Vref, and are centered on the servo groove of the servo layer and the mark row of the recording layer. It can be made to follow.
　図３５は本実施例の光ディスク装置の動作概要を示すフローチャートである。 FIG. 35 is a flowchart showing an outline of the operation of the optical disk apparatus of the present embodiment.
　ステップＳ６６０１において光ディスク装置に光ディスクが装着されたら、ステップＳ６６０２においてセットアップ処理を行う。セットアップ処理では情報の記録または再生を行うことが可能な状態にするためのディスク認識、フォーカス引き込み、トラッキング引き込み、収差調整、ディスク３３１の管理情報の再生などの各種処理が行われる。 If an optical disc is loaded in the optical disc apparatus in step S6601, setup processing is performed in step S6602. In the setup process, various processes such as disc recognition, focus pull-in, tracking pull-in, aberration adjustment, and reproduction of management information on the disc 331 are performed to make it possible to record or reproduce information.
　次にステップＳ６６０３においてホスト３３０からデータ再生コマンドを受け取ったら、ステップＳ６６０４においてデータ再生処理を行う。あるいはステップＳ６６０５においてホスト３３０からデータ記録コマンドを受け取ったら、ステップＳ６６０６においてデータ記録処理を行う。あるいはステップＳ６６０７においてホストコンピュータからその他のコマンドを受け取ったら、ステップＳ６６１０においてその他の処理を行う。また、ステップＳ６６０９において光ディスクが排出された場合は、処理を終了する。 Next, when a data reproduction command is received from the host 330 in step S6603, data reproduction processing is performed in step S6604. Alternatively, when a data recording command is received from the host 330 in step S6605, a data recording process is performed in step S6606. Alternatively, when another command is received from the host computer in step S6607, other processing is performed in step S6610. If the optical disk is ejected in step S6609, the process is terminated.
　図３６のフローチャートを用いてより図３５のデータ記録処理Ｓ６６０６を詳細に説明する。まず、ステップＳ７７０１において記録を行なう記録層ｎに４０５ｎｍの光スポットを移動させるフォーカスジャンプを行なう。次に、ステップＳ７７０２においてサーボ層に形成されたトラックから得られるサーボ層トラッキングエラー信号Ｓ＿ＴＥに基づいたトラッキング制御をオンし、ステップＳ７７０３において移動した記録層が未記録状態かを判定する。未記録状態かを判定する方法としては、例えばセットアップ処理Ｓ６６０２において取得したディスクの管理情報により行なう方法がある。 The data recording process S6606 in FIG. 35 will be described in detail with reference to the flowchart in FIG. First, in step S7701, a focus jump is performed to move a 405 nm light spot to the recording layer n to be recorded. Next, in step S7702, tracking control based on the servo layer tracking error signal S_TE obtained from the track formed on the servo layer is turned on. In step S7703, it is determined whether the recording layer that has moved is in an unrecorded state. As a method for determining whether or not it is in an unrecorded state, for example, there is a method performed based on disc management information acquired in the setup process S6602.
　ステップＳ７７０３において未記録ではないと判定した場合には、サーボ層のトラックから検出したサーボ層トラッキングエラー信号Ｓ＿ＴＥと記録層に記録されたマーク列からなるトラックから検出した記録層トラッキングエラー信号Ｒ＿ＴＥに基づいて生成された相対位置検出信号ＴＥによる相対位置制御をオンとし、サーボ層に照射される６５０ｎｍの光スポットの位置と記録層に照射される４０５ｎｍの光スポットの相対位置が保持されるとともに、サーボ層のトラックを光スポット３１１が追従するように制御が行われる。 If it is determined in step S7703 that it is not unrecorded, based on the servo layer tracking error signal S_TE detected from the track of the servo layer and the recording layer tracking error signal R_TE detected from the track formed of the mark row recorded on the recording layer. The relative position control by the relative position detection signal TE generated in this way is turned on, the position of the 650 nm light spot irradiated on the servo layer and the relative position of the 405 nm light spot irradiated on the recording layer are held, and the servo Control is performed so that the light spot 311 follows the track of the layer.
　システム制御回路２３０１から記録再生信号処理回路３３６には記録開始アドレス、記録データ等が設定され、ステップＳ７７０６で記録開始アドレスから記録を開始する。記録再生信号処理回路３３６では入力されたデータ及びアドレス情報をサーボ層から再生された信号から生成された基準クロック信号に基づいて所定の方式で変調し、レーザパワー制御回路１２０１に出力する。レーザパワー制御回路１２０１は記録再生信号処理回路３３６の出力に応じた駆動電流をレーザダイオード１２０２に出力し、レーザダイオード１２０２が対応した強度でレーザ光を出射することで光ディスク３３１の記録層に記録が行われる。ステップＳ７７０６で記録終了アドレスに一致したところで記録処理を終了する。 The system control circuit 2301 sets a recording start address, recording data, and the like in the recording / reproducing signal processing circuit 336, and recording starts from the recording start address in step S7706. The recording / reproducing signal processing circuit 336 modulates the input data and address information by a predetermined method based on the reference clock signal generated from the signal reproduced from the servo layer, and outputs the modulated data and address information to the laser power control circuit 1201. The laser power control circuit 1201 outputs a drive current corresponding to the output of the recording / reproducing signal processing circuit 336 to the laser diode 1202, and the laser diode 1202 emits laser light with a corresponding intensity, whereby recording is performed on the recording layer of the optical disc 331. Done. In step S7706, the recording process is terminated when it coincides with the recording end address.
　ステップＳ７７０３における未記録状態の判定は、記録層トラッキングエラー信号Ｒ＿ＴＥの振幅により行なうこともできる。記録されている状態であれば、光スポット３０１と記録層に記録されたマーク列からなるトラックとのずれに応じて記録層トラッキングエラー信号Ｒ＿ＴＥが変化するが、記記録されていない状態では基準電圧Ｖｒｅｆ近傍となっている。従って、ステップＳ７７０１で記録層ｎにフォーカスジャンプを行い、トラッキング制御がオフした状態での記録層トラッキングエラー信号Ｒ＿ＴＥの振幅により未記録状態の判定を行なうことができる。 Determination of the unrecorded state in step S7703 can also be performed based on the amplitude of the recording layer tracking error signal R_TE. In the recorded state, the recording layer tracking error signal R_TE changes according to the deviation between the light spot 301 and the track formed by the mark row recorded in the recording layer, but in the unrecorded state, the reference voltage It is near Vref. Accordingly, a focus jump is performed on the recording layer n in step S7701, and the unrecorded state can be determined based on the amplitude of the recording layer tracking error signal R_TE in a state where the tracking control is turned off.
　また、記録層に照射される光スポット３０１と３０２のディスクからの反射光量により、記録時において光スポット３０１が記録済のマーク列からなるトラックを追従しながら所定のトラックの間隔で正常に記録しているかを確認することができる。 例えば記録マークが形成されると反射率が低くなる光ディスク３３１であれば記録マークを追従している光スポット３０１の総反射光量に対応するＲ＿ＳＵＭ信号に比べて未記録にある光スポット３０２の総反射光量に対応するＦ＿ＳＵＭ信号の信号レベルが大きくなる。従って、Ｒ＿ＳＵＭ信号振幅よりもＦ＿ＳＵＭ信号振幅が大きい場合には正常な記録状態であり、Ｆ＿ＳＵＭ信号振幅よりもＲ＿ＳＵＭ信号振幅が大きい場合には記録状態が異常として記録を停止する等の処理を行なうことができる。光ディスク１０１が記録マークが形成されると反射率が高くなるであれば、前述のＦ＿ＳＵＭ信号とＲ＿ＳＵＭ信号の振幅の大小が逆転する。 In addition, the light spot 301 and the light spot 301 irradiated on the recording layer are normally recorded at a predetermined track interval while the light spot 301 follows a track made up of recorded mark rows during recording. It can be confirmed. For example, in the case of the optical disc 331 that has a low reflectance when a recording mark is formed, the total reflection of the light spot 302 that has not been recorded compared to the R_SUM signal corresponding to the total reflected light amount of the light spot 301 that follows the recording mark. The signal level of the F_SUM signal corresponding to the amount of light increases. Therefore, when the F_SUM signal amplitude is larger than the R_SUM signal amplitude, the recording state is normal, and when the R_SUM signal amplitude is larger than the F_SUM signal amplitude, the recording state is abnormal and recording is stopped. Can do. If the reflectance increases when the recording mark is formed on the optical disc 101, the magnitudes of the amplitudes of the F_SUM signal and the R_SUM signal are reversed.
　また、記録マークに追従している光スポット３０１と光スポット３１１の位置を記録再生信号処理回路３３６にてアドレスとして読み取れるため、このアドレスを記録時の記録が適切な位置と適切な記録層にて行われているかの確認に使用しても良い。 Further, since the position of the light spot 301 and the light spot 311 following the recording mark can be read as an address by the recording / reproducing signal processing circuit 336, this address is recorded at an appropriate position and an appropriate recording layer. It may be used to check if it is being performed.
　また、前述したステップＳ７７０３で未記録と判定した場合にも、ディスク１回転以上記録を行なうと記録マーク列からなるトラックが形成されるため、光スポット３０１にて記録層トラッキングエラー信号Ｒ＿ＴＥを生成することが可能となる。従って、記録開始後に１回転以上の記録を行なった時点で相対位置制御をオンするようにしても良い。或いは、一度記録を止めて相対位置制御をオンした後に再度記録を開始しても良い。 Even when it is determined that recording has not been performed in step S7703, a recording layer tracking error signal R_TE is generated at the light spot 301 because a track including a recording mark row is formed when recording is performed once or more times on the disc. It becomes possible. Therefore, the relative position control may be turned on at the time when one or more rotations are recorded after the start of recording. Alternatively, recording may be stopped and recording may be started again after the relative position control is turned on.
　　本実施例ではステップＳ７７０１でフォーカスジャンプを行なった後に、記録層においてフォーカスのみ制御がオンで相対位置制御はオフとしてが、記録マークが無ければ記録層トラッキングエラー信号Ｒ＿ＴＥはＶｒｅｆ近傍であるため、相対位置制御をオンにしても影響は無い。このため相対位置制御をオンにしておき、記録マークが形成されると、その記録マークからＲ＿ＴＥを生成し相対位置制御にて記録マークに光スポット３０１を追従させることも可能である。 In this embodiment, after performing the focus jump in step S7701, only the focus control is turned on and the relative position control is turned off in the recording layer. However, if there is no recording mark, the recording layer tracking error signal R_TE is near Vref. Turning on position control has no effect. Therefore, when the relative position control is turned on and a recording mark is formed, it is possible to generate R_TE from the recording mark and cause the light spot 301 to follow the recording mark by the relative position control.
　以上の実施例におけるフローチャートは主たるステップを記載したものであり、各ステップの間に他のステップを設けるようにしても良い。また、光ディスク装置の動作として不都合が生じない範囲でステップの順序を変えるようにしてもよい。
また、本実施例において、サーボ層は１ビームによりフォーカス制御、トラッキング制御を行っている例であるが、例えばビームスプリッタ１２１７と偏向ビームスプリッタ１２２０の間にグレーティングをおいて３ビーム（メインビーム０次光及びそのサーボビーム±１次光）としても良い。本実施例におけるサーボエラー信号生成回路１０５にて生成される信号はトラッキング信号であれば差動プッシュプル法（ＤＰＰ法）やプッシュプル法、フォーカス信号であればナイフエッジ法や差動非点収差方式などの方式を用いて行えばよい。ただし、前述の方式は限定するものではなく異なる方式であっても良い。 The flowcharts in the above embodiments describe the main steps, and other steps may be provided between the steps. Further, the order of the steps may be changed within a range that does not cause inconvenience as the operation of the optical disc apparatus.
In this embodiment, the servo layer is an example in which focus control and tracking control are performed by one beam. For example, a grating is provided between the beam splitter 1217 and the deflecting beam splitter 1220 to provide three beams (main beam 0th order). Light and its servo beam ± primary light). In the present embodiment, the signal generated by the servo error signal generation circuit 105 is a differential push-pull method (DPP method) or push-pull method if it is a tracking signal, and a knife-edge method or differential astigmatism if it is a focus signal. A method such as a method may be used. However, the above-described method is not limited and may be a different method.
　(本実施例の特徴)
本実施例の特徴は、記録層に記録済みのマークが存在する場合にサーボ層に照射した光スポット３１１をサーボ層のトラックに追従させる共に、光スポット３０１が記録済みのマーク列に追従するよう相対位置を制御することで、サーボ層に照射される６５０ｎｍの光スポットの位置と記録層に照射される４０５ｎｍの光スポットのトラック方向の相対位置を保持し、所定のトラック間隔で記録を行なうことが可能となる。これにより、追加記録する際にレーザ光と光ディスクの相対角度が温度や光ディスクのチャッキング状態等により前回記録したときから変化した場合にでも前回記録したデータに上書きすることを抑制することができ、無駄な領域を設けることなく追加記録を行うことが可能となる。 (Features of this embodiment)
The feature of this embodiment is that when a recorded mark exists in the recording layer, the light spot 311 irradiated to the servo layer follows the track of the servo layer, and the light spot 301 follows the recorded mark row. By controlling the relative position, the relative position in the track direction of the 650 nm light spot irradiated on the servo layer and the 405 nm light spot irradiated on the recording layer is maintained, and recording is performed at a predetermined track interval. Is possible. Thereby, it is possible to suppress overwriting the previously recorded data even when the relative angle between the laser beam and the optical disk changes from the previous recording due to temperature, the chucking state of the optical disk, etc. during additional recording, Additional recording can be performed without providing a useless area.
　また、記録時においても基準となるクロック信号等をサーボ層のトラックから得られる情報から生成することができる。 Also, a reference clock signal or the like can be generated from information obtained from the servo layer track even during recording.
  本発明における第２の実施例について、以下に説明する。 A second embodiment of the present invention will be described below.
　本実施例に従った相対位置制御を実施するための光ディスク装置の一例を図３７に示す。図３０との違いは光ピックアップ３３２に角度可変立ち上げミラー１２２７を設け、光軸角度可変素子駆動回路３４２により相対位置制御を実現する点である。また、第５の実施例にて説明した内容と重複する部分については省略する。 FIG. 37 shows an example of an optical disk apparatus for performing relative position control according to the present embodiment. The difference from FIG. 30 is that the optical pickup 332 is provided with a variable angle rising mirror 1227 and the relative position control is realized by the optical axis angle variable element driving circuit 342. Further, the description overlapping with the contents described in the fifth embodiment is omitted.
　(本実施例の実現手段)
図３７の光ディスク装置は、光ピックアップ３３２と、信号処理回路３３３と、スピンドルモータ３３４と、サーボエラー信号生成回路３３５と、記録再生信号処理回路３３６と、スピンドル駆動回路３３７と、アクチュエータ駆動回路３３８と、リレーレンズ駆動回路３３９と、収差補正素子駆動回路３４０と、光軸角度可変素子駆動回路３４２で構成される。 (Means for realizing the present embodiment)
37 includes an optical pickup 332, a signal processing circuit 333, a spindle motor 334, a servo error signal generation circuit 335, a recording / reproduction signal processing circuit 336, a spindle driving circuit 337, and an actuator driving circuit 338. , A relay lens driving circuit 339, an aberration correction element driving circuit 340, and an optical axis angle variable element driving circuit 342.
　まず、４０５ｎｍの光学系について説明する。レーザパワー制御回路１２０１は、システム制御回路２３０１によって制御されており、レーザダイオード１２０２を駆動する電流を出力する。この駆動電流は、レーザノイズを抑制するために数百ＭＨｚの高周波重畳が印加されている。レーザダイオード１２０２は、駆動電流に応じた波形で波長４０５ｎｍのレーザ光を出射する。出射されたレーザ光はコリメータレンズ１２０３にて平行光となり、ビームスプリッタ１２０４で一部が反射し、集光レンズ１２０５によってパワーモニタ１２０６に集光する。一方、ビームスプリッタ１２０４を透過したレーザ光は３ビーム仕様のグレーティング３４１により複数の光ビーム（メインビーム０次光及びそのサーボビーム±１次光）となり、偏光ビームスプリッタ１２０７にて反射し、収差補正素子駆動回路１１０にて駆動される収差補正素子１２０９によって収束・発散が制御され、ダイクロイックミラー１２０８を透過する。ダイクロイックミラー１２０８は特定の波長の光を反射し、その他の波長の光を透過する光学素子である。ここでは波長４０５ｎｍの光を透過し、６５０ｎｍの光を反射するものとする。ダイクロイックミラー１２０８を透過したレーザ光は、角度可変立ち上げミラー１２２７により反射され、１／４波長板１２１０にて円偏光となり、対物レンズ１２１１によって光ディスク３３１の記録層に集光する。後述するように角度可変立ち上げミラー１２２７は、ミラーの角度を変化させて反射光の光軸方向を変化可能な角度可変立ち上げミラーである。対物レンズ１２１１は、アクチュエータ１２１２によって位置制御される。光ディスク３３１によって反射したレーザ光は、光ディスク３３１に記録された情報に応じて強度が変調され、１／４波長板１２１０にて直線偏光となり、角度可変立ち上げミラー１２２７で反射しダイクロイックミラー１２０８および収差補正素子１２０９を経て、偏光ビームスプリッタ１２０７を透過する。透過したレーザ光は、集光レンズ１２１３によってディテクタ１２１４に集光する。ディテクタ１２１４はレーザ光の強度を検出し、これに応じた信号をサーボエラー信号生成回路３３５及び記録再生信号処理回路３３６に対して出力する。 First, the 405 nm optical system will be described. The laser power control circuit 1201 is controlled by the system control circuit 2301 and outputs a current for driving the laser diode 1202. This driving current is applied with high frequency superposition of several hundred MHz in order to suppress laser noise. The laser diode 1202 emits laser light having a wavelength of 405 nm with a waveform corresponding to the drive current. The emitted laser light is converted into parallel light by the collimator lens 1203, partly reflected by the beam splitter 1204, and condensed on the power monitor 1206 by the condenser lens 1205. On the other hand, the laser light transmitted through the beam splitter 1204 is converted into a plurality of light beams (main beam 0th order light and its servo beam ± 1st order light) by the grating 341 of the three beam specification, reflected by the polarization beam splitter 1207, and corrected for aberration. Convergence / divergence is controlled by the aberration correction element 1209 driven by the element driving circuit 110, and passes through the dichroic mirror 1208. The dichroic mirror 1208 is an optical element that reflects light of a specific wavelength and transmits light of other wavelengths. Here, it is assumed that light having a wavelength of 405 nm is transmitted and light having a wavelength of 650 nm is reflected. The laser beam that has passed through the dichroic mirror 1208 is reflected by the angle-variable rising mirror 1227, becomes circularly polarized light by the quarter-wave plate 1210, and is condensed on the recording layer of the optical disk 331 by the objective lens 1211. As will be described later, the variable angle rising mirror 1227 is a variable angle rising mirror that can change the optical axis direction of reflected light by changing the angle of the mirror. The position of the objective lens 1211 is controlled by the actuator 1212. The intensity of the laser light reflected by the optical disk 331 is modulated according to the information recorded on the optical disk 331, becomes linearly polarized light by the quarter-wave plate 1210, is reflected by the angle-variable rising mirror 1227, and is reflected by the dichroic mirror 1208 and aberration. The light passes through the correction element 1209 and passes through the polarization beam splitter 1207. The transmitted laser light is condensed on the detector 1214 by the condenser lens 1213. The detector 1214 detects the intensity of the laser beam and outputs a signal corresponding to the intensity to the servo error signal generation circuit 335 and the recording / reproduction signal processing circuit 336.
　次に、６５０ｎｍの光学系について説明する。４０５ｎｍの光学系と同様に、レーザパワー制御回路１２０１がレーザダイオード１２１５を駆動し、レーザダイオード１２１５は波長６５０ｎｍのレーザ光を出射する。レーザ光の一部は、コリメータレンズ１２１６、ビームスプリッタ１２１７、集光レンズ１２１８を経て、パワーモニタ１２１９にてパワーがモニタされる。ビームスプリッタ１２１７を透過したレーザ光は、偏光ビームスプリッタ１２２０を透過し、リレーレンズ１２２１に入射する。リレーレンズ１２２１はアクチュエータ１２２８により駆動され、サーボ層に照射される光スポットのフォーカス方向の位置の制御が行われる。リレーレンズ１２２１を経たレーザ光は、ダイクロイックミラー１２０８、角度可変立ち上げミラー１２２７にて反射し、１／４波長板１２１０を経て、対物レンズ１２１１により光ディスク３３１のサーボ層に集光する。光ディスク３３１にて反射したレーザ光を偏光ビームスプリッタ１２２０にて反射し、集光レンズ１２２２にてディテクタ１２２３に集光する。ディテクタ１２２３はレーザ光の強度を検出し、これに応じた信号をサーボエラー信号生成回路３３５及び記録再生信号処理回路３３６に対して出力する。 Next, the 650 nm optical system will be described. Similar to the 405 nm optical system, the laser power control circuit 1201 drives the laser diode 1215, and the laser diode 1215 emits laser light having a wavelength of 650 nm. A part of the laser light passes through a collimator lens 1216, a beam splitter 1217, and a condenser lens 1218, and the power is monitored by a power monitor 1219. The laser light that has passed through the beam splitter 1217 passes through the polarization beam splitter 1220 and enters the relay lens 1221. The relay lens 1221 is driven by an actuator 1228 to control the position of the light spot irradiated on the servo layer in the focus direction. The laser light that has passed through the relay lens 1221 is reflected by the dichroic mirror 1208 and the variable angle raising mirror 1227, passes through the quarter-wave plate 1210, and is condensed on the servo layer of the optical disk 331 by the objective lens 1211. The laser beam reflected by the optical disk 331 is reflected by the polarization beam splitter 1220 and condensed on the detector 1223 by the condenser lens 1222. The detector 1223 detects the intensity of the laser beam and outputs a signal corresponding to the intensity to the servo error signal generation circuit 335 and the recording / reproduction signal processing circuit 336.
　次に、本実施例における相対位置制御について説明する。情報の記録時において、一定のトラックピッチ間隔で記録マーク列を記録するには、波長４０５ｎｍの光スポットと波長６５０ｎｍの光スポットの光軸の相対関係を保持する制御が必要である。そこで、この異なる２つの波長の光軸の相対関係を制御するために、サーボ層トラッキングエラー信号Ｓ＿ＴＥ、記録層トラッキングエラー信号Ｒ＿ＴＥ及びその差分から得られるＴＥをサーボエラー信号生成回路３３５で生成する。ここで、サーボ層トラッキングエラー信号Ｓ＿ＴＥはサーボ層のトラックに追従しているときの信号であるため光軸の基準軸としている。この基準軸からの誤差はディスクのチルト等により生じるため、この基準軸からの誤差を光軸角度可変素子駆動回路３４２に入力し角度可変立ち上げミラー１２２７を制御することでミラーの角度を変えて、この誤差を最小にする制御を行う。この結果、光軸の相対関係を保持することができるため記録済みの領域に上書き記録することを抑制することが可能となる。 Next, the relative position control in this embodiment will be described. In recording information, in order to record a record mark row at a constant track pitch interval, it is necessary to control to maintain the relative relationship between the optical spots of the light spot having a wavelength of 405 nm and the light spot having a wavelength of 650 nm. Therefore, in order to control the relative relationship between the optical axes of the two different wavelengths, the servo layer tracking error signal S_TE, the recording layer tracking error signal R_TE, and TE obtained from the difference are generated by the servo error signal generation circuit 335. Here, since the servo layer tracking error signal S_TE is a signal when following the track of the servo layer, it is used as the reference axis of the optical axis. Since the error from the reference axis is caused by the tilt of the disk or the like, the error from the reference axis is input to the optical axis angle variable element drive circuit 342 and the angle of the mirror is changed by controlling the angle variable raising mirror 1227. Then, control is performed to minimize this error. As a result, since the relative relationship of the optical axes can be maintained, overwriting in the recorded area can be suppressed.
　相対位置検出回路２３１２は、システム制御回路２３０１からの指令信号により、相対位置検出信号ＴＥに対してゲインと位相の補償を行い、相対位置制御を行うための駆動信号を出力する。相対位置検出回路２３１２から出力された駆動信号ＴＬＤは、スイッチ２３１４を介して光学角度可変素子駆動回路１１２に入力される。この光学角度可変素子駆動回路１１２により角度可変立ち上げミラー１２２７を駆動すると４０５ｎｍと６５０ｎｍの光軸が変化する。この光軸の変化はサーボ層トラッキングエラー信号Ｓ＿ＴＥの変位にもなる。しかし、サーボ層トラッキング制御系により対物レンズ１２１１のアクチュエータ１２１２が駆動されるので、光スポット３１１がサーボ層のトラックを追従するように動作する。この結果、４０５ｎｍと６５０ｎｍの光軸の相対関係を保持することができる。 The relative position detection circuit 2312 compensates the relative position detection signal TE for gain and phase in response to a command signal from the system control circuit 2301, and outputs a drive signal for performing relative position control. The drive signal TLD output from the relative position detection circuit 2312 is input to the optical angle variable element drive circuit 112 via the switch 2314. When the variable angle rising mirror 1227 is driven by the optical angle variable element driving circuit 112, the optical axes of 405 nm and 650 nm change. This change in the optical axis also becomes a displacement of the servo layer tracking error signal S_TE. However, since the actuator 1212 of the objective lens 1211 is driven by the servo layer tracking control system, the light spot 311 operates so as to follow the track of the servo layer. As a result, the relative relationship between the optical axes of 405 nm and 650 nm can be maintained.
　スイッチ２３１４はシステム制御回路２３０１の出力するＴＯＮ信号に基づき、相対位置検出回路２３１２の出力信号もしくは基準電位Ｖｒｅｆを選択して、ＴＬＤとして光学角度可変素子駆動回路３４２に出力される。
相対位置制御がオンし、光軸角度可変素子駆動回路３４２により角度可変立ち上げミラー１２２７を駆動すると、４０５ｎｍと６５０ｎｍの光軸の相対関係が変化する。これにより、サーボ層に照射された光スポット３１１がトラック方向に変位し、サーボ層トラッキングエラー信号Ｓ＿ＴＥが変化する。このサーボ層トラッキングエラー信号Ｓ＿ＴＥの変化に対して、サーボ層トラッキング制御系により対物レンズ１２１１のアクチュエータ１２１２を駆動し、光スポット３１１がサーボ層のトラックを追従するように動作する。従って、相対位置制御による光スポット３１１のトラック方向へずれを抑制するためにはサーボ層トラッキング制御系の制御帯域よりも相対位置制御系の制御帯域が低くなるようにする必要がある。このため、例えば低域通過フィルタで相対位置検出信号ＴＥの周波数帯域制限を行う、或いは角度可変立ち上げミラー１２２７の周波数応答特性を対物レンズ１２１１のアクチュエータ１２１２の周波数応答特性より低くしても良い。これにより、サーボ層に照射される６５０ｎｍの光スポットの位置と記録層に照射される４０５ｎｍの光スポットのトラック方向の相対位置が保持されるとともに、サーボ層のトラックを光スポット３１１が追従するように制御が行われる。 The switch 2314 selects the output signal of the relative position detection circuit 2312 or the reference potential Vref based on the TON signal output from the system control circuit 2301, and outputs the selected signal as a TLD to the optical angle variable element driving circuit 342.
When the relative position control is turned on and the variable angle rising mirror 1227 is driven by the variable optical axis angle element driving circuit 342, the relative relationship between the optical axes of 405 nm and 650 nm changes. Thereby, the light spot 311 irradiated to the servo layer is displaced in the track direction, and the servo layer tracking error signal S_TE changes. In response to the change in the servo layer tracking error signal S_TE, the servo layer tracking control system drives the actuator 1212 of the objective lens 1211 so that the light spot 311 follows the track of the servo layer. Therefore, in order to suppress the deviation of the light spot 311 in the track direction due to the relative position control, it is necessary to make the control band of the relative position control system lower than the control band of the servo layer tracking control system. For this reason, for example, the frequency band of the relative position detection signal TE may be limited by a low-pass filter, or the frequency response characteristic of the variable angle raising mirror 1227 may be made lower than the frequency response characteristic of the actuator 1212 of the objective lens 1211. Thereby, the relative position in the track direction of the 650 nm light spot irradiated to the servo layer and the 405 nm light spot irradiated to the recording layer is maintained, and the light spot 311 follows the track of the servo layer. Control is performed.
　第５の実施例の場合と同様、図３４（ａ）に示すように記録層トラッキングエラー信号Ｒ＿ＴＥが基準電圧のＶｒｅｆからＶａのオフセットが生じた場合、Ｖａに相当するオフセットをキャンセルするように角度可変立ち上げミラー１２２７を制御する。この場合には、内周方向にオフセットしているため、角度可変立ち上げミラー１２２７を外周方向相当する反時計周りにＶａに相当する角度だけ駆動する。これによりオフセットをキャンセルする。このときの光軸可変素子１２２７の動作を図３８に模式的に示す。図３８は図３７の光ピックアップ３３２の一部を示したものである。図に示すように６５０ｎｍのレーザ光と４０５ｎｍのレーザ光がダイクロイックミラー１２０８にて同一の光路となり、角度可変立ち上げミラー１２２７の角度に応じて反射光の光軸方向が変化する。例えば、図３４（ａ）のＶａをキャンセルするために図３８（ａ）から図３８（ｂ）に示すように角度可変立ち上げミラー１２２７が反時計周りに回転することで、４０５ｎｍと６５０ｎｍの光軸を調整する。これにより、図３４（ｂ）に示すように、サーボ層トラッキングエラー信号Ｓ＿ＴＥ、記録層トラッキングエラー信号Ｒ＿ＴＥともに基準電圧のＶｒｅｆ近傍で動作し、サーボ層のトラックおよび記録層のマーク列の中心に追従している状態にすることができる。 As in the case of the fifth embodiment, when the recording layer tracking error signal R_TE has an offset of Va from the reference voltage Vref as shown in FIG. 34A, an angle is set so as to cancel the offset corresponding to Va. The variable raising mirror 1227 is controlled. In this case, since it is offset in the inner circumferential direction, the variable angle raising mirror 1227 is driven counterclockwise corresponding to the outer circumferential direction by an angle corresponding to Va. This cancels the offset. The operation of the optical axis variable element 1227 at this time is schematically shown in FIG. FIG. 38 shows a part of the optical pickup 332 of FIG. As shown in the figure, the 650 nm laser beam and the 405 nm laser beam have the same optical path in the dichroic mirror 1208, and the optical axis direction of the reflected light changes according to the angle of the variable angle raising mirror 1227. For example, in order to cancel Va in FIG. 34 (a), the angle variable raising mirror 1227 rotates counterclockwise as shown in FIGS. 38 (a) to 38 (b), so that light of 405 nm and 650 nm can be obtained. Adjust the axis. As a result, as shown in FIG. 34B, both the servo layer tracking error signal S_TE and the recording layer tracking error signal R_TE operate in the vicinity of the reference voltage Vref, and follow the center of the servo layer track and the mark layer of the recording layer. Can be in a state of being.
　(本実施例の特徴)
　実施例５ではリレーレンズ１２２１をアクチュエータ１２２８によりトラック方向に駆動することで相対位置制御を行い波長４０５ｎｍの光スポットと波長６５０ｎｍの光スポットの光軸の相対関係を保持する例であったが、本実施例ではリレーレンズ１２２１のアクチュエータ１２２８ではなく角度可変立ち上げミラー１２２７で実現する点が異なる。本実施例による効果としては、記録済みのマーク列がディスク半径方向に一定の間隔で記録されるため、光ディスクの経時変化による反りや記録装置の違い等による２つのレーザビームの光軸に対して光ディスクにチルトが存在していても記録済みの領域に上書き記録することを抑制できる。また、光ディスクの経時変化だけではなく、光ディスクのもつディスクの反りや記録層とサーボ層の層内の偏差によって発生する２つのレーザビームの光軸に対して光ディスクにチルトが存在していても記録済みの領域に上書き記録することを抑制することができる。 (Features of this embodiment)
In the fifth embodiment, the relative position is controlled by driving the relay lens 1221 in the track direction by the actuator 1228, and the relative relationship between the optical axis of the light spot having the wavelength of 405 nm and the light spot having the wavelength of 650 nm is maintained. This embodiment is different from the embodiment in that it is realized not by the actuator 1228 of the relay lens 1221 but by the variable angle raising mirror 1227. As an effect of the present embodiment, since recorded mark rows are recorded at a constant interval in the radial direction of the disc, the optical axis of the two laser beams is caused by warpage due to aging of the optical disc or differences in recording devices. Even if there is tilt on the optical disc, it is possible to suppress overwriting in the recorded area. Further, not only the change of the optical disc over time but also the optical disc can be recorded even if the optical disc is tilted with respect to the optical axes of the two laser beams generated by the warpage of the optical disc and the deviation between the recording layer and the servo layer. It is possible to suppress overwriting recording in a completed area.
　本実施例の光学系では、光軸角度可変素子として角度可変立上げミラー１２２７を搭載し、４０５ｎｍと６５０ｎｍの両方の光軸を調整するようにしている。例えば、４０５ｎｍと６５０ｎｍの片方の光軸のみを調整できる位置に角度可変立上げミラー１２２７を配置しても良い。角度可変立上げミラーとしては、例えばガルバノミラー或いはＭＥＭＳ（Micro Electro Mechanical Systems）ミラーなどを用いることができる。これにより、ディスクの傾斜状態が記録時に変化する場合、その変化量に合わせて角度可変立立上げミラー１２２７の角度を変化させ、ディスクへのビーム入射角度を変える。このような入射角度の補正を行うことで、記録済のマークを走査できるため、書き換え可能なディスクに対し安定したイレーズ動作と書き換え動作を行うことができる。また追加記録時には、無駄な領域を設けることなく記録済の領域から連続して新たな情報を記録することが可能となる。 In the optical system of the present embodiment, a variable angle rising mirror 1227 is mounted as an optical axis angle variable element, and both the optical axes of 405 nm and 650 nm are adjusted. For example, the variable angle rising mirror 1227 may be disposed at a position where only one of the optical axes of 405 nm and 650 nm can be adjusted. As the variable angle raising mirror, for example, a galvano mirror or a MEMS (Micro Electro Mechanical Systems) mirror can be used. As a result, when the tilt state of the disk changes during recording, the angle of the variable angle rising mirror 1227 is changed in accordance with the change amount to change the beam incident angle to the disk. By correcting the incident angle as described above, the recorded mark can be scanned, so that a stable erase operation and rewrite operation can be performed on a rewritable disc. Further, at the time of additional recording, new information can be continuously recorded from the recorded area without providing a useless area.
　以上の実施例では物理的な溝構造を持つサーボ層と、ランド/グルーブ構造と言った物理的な溝構造を持たない複数の記録層からなるグルーブレスディスクに対応した光ディスク装置について説明を行なったが、溝構造を持つサーボ層と層構造を持たない記録層に深さ方向の焦点位置を変えながら記録を行なうマイクロホログラム或いは２光子吸収などの原理を用いた体積記録方式の光ディスクにも対応することが可能である。要は記録層に記録されたマーク列からなるトラックからの反射光量に基づいて記録層トラッキングエラー信号を検出し、サーボ層のトラックからの反射光量に基づいて生成されたサーボ層トラッキングエラー信号を用いて相対位置を検出することによりグルーブレスディスクと同様に対応することが可能である。 In the above embodiments, an optical disk apparatus corresponding to a grooveless disk composed of a servo layer having a physical groove structure and a plurality of recording layers having no physical groove structure such as a land / groove structure has been described. However, it also supports micro-holograms that record while changing the focal position in the depth direction on a servo layer with a groove structure and a recording layer that does not have a layer structure, or volume recording optical disks that use principles such as two-photon absorption It is possible. In short, the recording layer tracking error signal is detected based on the amount of reflected light from the track consisting of the mark row recorded on the recording layer, and the servo layer tracking error signal generated based on the amount of reflected light from the track of the servo layer is used. By detecting the relative position, it is possible to deal with the same as a grooveless disk.
　また、図３４とは異なる場合を図３９に示す。この図３９ではサーボ層トラッキングエラー信号Ｓ＿ＴＥの変位に基づいて対物レンズ１２１１は制御されるため、ディスク１０１のディスクチルトやディスクの偏心は抑圧される。しかし、記録層トラッキングエラー信号Ｒ＿ＴＥには図３９のようなディスク１回転周期に同期する変位がのることになる。この場合には、ディスク１回転周期で変化する成分を打ち消すようなＴＥがサーボエラー信号生成回路３３５から生成される。このようにＴＥは時間的に変化しない信号であっても良いし変化する信号であっても良い。更にサーボ層トラッキングエラー信号Ｓ＿ＴＥ、記録層トラッキングエラー信号Ｒ＿ＴＥの周波数と振幅が一致しなくても良い。 FIG. 39 shows a case different from FIG. In FIG. 39, since the objective lens 1211 is controlled based on the displacement of the servo layer tracking error signal S_TE, the disc tilt of the disc 101 and the eccentricity of the disc are suppressed. However, the recording layer tracking error signal R_TE is displaced in synchronism with one rotation period of the disk as shown in FIG. In this case, a TE that cancels a component that changes in one rotation period of the disk is generated from the servo error signal generation circuit 335. Thus, TE may be a signal that does not change with time or a signal that changes. Furthermore, the frequency and amplitude of the servo layer tracking error signal S_TE and the recording layer tracking error signal R_TE do not need to match.
　なお、本発明は上記した実施例に限定されるものではなく、様々な変形例が含まれる。例えば、上記した実施例は本発明を分かりやすく説明するために詳細に説明したものであり、必ずしも説明した全ての構成を備えるものに限定されるものではない。また、ある実施例の構成の一部を他の実施例の構成に置き換えることが可能であり、また、ある実施例の構成に他の実施例の構成を加えることも可能である。また、各実施例の構成の一部について、他の構成の追加・削除・置換をすることが可能である。 In addition, this invention is not limited to the above-mentioned Example, Various modifications are included. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. Further, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. Further, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.
　また、上記の各構成は、それらの一部又は全部が、ハードウェアで構成されても、プロセッサでプログラムが実行されることにより実現されるように構成されてもよい。また、制御線や情報線は説明上必要と考えられるものを示しており、製品上必ずしも全ての制御線や情報線を示しているとは限らない。実際には殆ど全ての構成が相互に接続されていると考えてもよい。 In addition, each of the above-described configurations may be configured such that a part or all of the configuration is configured by hardware, or is realized by executing a program by a processor. Further, the control lines and information lines indicate what is considered necessary for the explanation, and not all the control lines and information lines on the product are necessarily shown. Actually, it may be considered that almost all the components are connected to each other.
１０１…光ディスク装置
１０２…光ディスク
１０３…光ピックアップ
１０４…信号処理回路
１０５…サーボエラー信号生成回路
１０６…信号処理回路
１０７…スピンドルモータ
１０８…スピンドル駆動回路
１０９…アクチュエータ駆動回路
１１０…リレーレンズ駆動回路
１１１…収差補正素子駆動回路
１１２…スライダモータ
１１３…スライダ駆動回路
１１４…ホスト
１３０１…レーザパワー制御回路
１３０２…レーザダイオード
１３０３…コリメータレンズ
１３０４…ビームスプリッタ
１３０５…集光レンズ
１３０６…パワーモニタ
１３０７…偏光ビームスプリッタ
１３０８…ダイクロイックミラー
１３０９…収差補正素子
１３１０…１／４波長板
１３１１…対物レンズ
１３１２…アクチュエータ
１３１３…集光レンズ
１３１４…ディテクタ
１３１５…レーザダイオード
１３１６…コリメータレンズ
１３１７…ビームスプリッタ
１３１８…集光レンズ
１３１９…パワーモニタ
１３２０…偏光ビームスプリッタ
１３２１…リレーレンズ
１３２２…集光レンズ
１３２３…ディテクタ
１３２４…ディテクタ
１４０１…記録層Ｓｕｂトラッキングエラー信号生成回路
１４０２…記録層Ｍａｉｎトラッキングエラー信号生成回路
１４０３…サーボ層トラッキングエラー信号生成回路
１４０４…記録層フォーカスエラー信号生成回路
１４０５…サーボ層フォーカスエラー信号生成回路
１５０１…システム制御回路
１５０２…記録層フォーカス制御回路
１５０３…スイッチ
１５０４…記録層フォーカス駆動電圧生成回路
１５０５…加算器
１５０６…サーボ層フォーカス制御回路
１５０７…スイッチ
１５０８…サーボ層フォーカス駆動電圧生成回路
１５０９…加算器
１５１０…サーボ層トラッキング制御回路
１５１１…スイッチ
１５１２…セレクタ
１５１３…セレクタ
１５１４…記録層トラックピッチ調整電圧生成回路
１５１５…加算器
１５１６…記録層トラッキング制御回路
１５１７…スイッチ
１５１８…セレクタ
１５１９…トラッキング駆動電圧生成回路
１５２０…加算器
１５２１…スライダ制御回路
１５２２…スピンドル制御回路
１５２３…記録層ＭａｉｎＴＥ信号モニタ回路
221 光ディスク記録再生装置
222 光ディスク
500 光スポット
501 光スポット
502 光スポット
511 光スポット
1101 前SUBトラッキング誤差信号生成手段
1102 Mainトラッキング誤差信号生成手段
1103 後SUBトラッキング誤差信号生成手段
1104 トラッキング誤差信号選択手段
３３１…光ディスク
３３２…光ピックアップ
３３３…信号処理回路
３３４…スピンドルモータ
３３５…サーボエラー信号生成回路
３３６…記録再生信号処理回路
３３８…アクチュエータ駆動回路
３３９…リレーレンズ駆動回路
３４０…収差補正素子駆動回路
３４１…グレーティング
３４２…光軸角度可変素子駆動回路
１２０２…レーザダイオード
１２０９…収差補正素子
１２１１…対物レンズ
１２１２…アクチュエータ
１２２１…リレーレンズ
１２２７…角度可変立ち上げミラー
１２２８…アクチュエータ
２３０１…システム制御回路
２３１０…トラッキング制御回路
２３１２…相対位置制御回路 DESCRIPTION OF SYMBOLS 101 ... Optical disk apparatus 102 ... Optical disk 103 ... Optical pick-up 104 ... Signal processing circuit 105 ... Servo error signal generation circuit 106 ... Signal processing circuit 107 ... Spindle motor 108 ... Spindle drive circuit 109 ... Actuator drive circuit 110 ... Relay lens drive circuit 111 ... Aberration correction element drive circuit 112 ... slider motor 113 ... slider drive circuit 114 ... host 1301 ... laser power control circuit 1302 ... laser diode 1303 ... collimator lens 1304 ... beam splitter 1305 ... condensing lens 1306 ... power monitor 1307 ... polarization beam splitter 1308 ... Dichroic mirror 1309 ... Aberration correction element 1310 ... 1/4 wavelength plate 1311 ... Objective lens 1312 ... Actuator 1313 ... Condensing lens 1314 ... Detec 1315: Laser diode 1316 ... Collimator lens 1317 ... Beam splitter 1318 ... Condensing lens 1319 ... Power monitor 1320 ... Polarizing beam splitter 1321 ... Relay lens 1322 ... Condensing lens 1323 ... Detector 1324 ... Detector 1401 ... Recording layer Sub tracking error signal generation Circuit 1402 ... Recording layer Main tracking error signal generation circuit 1403 ... Servo layer tracking error signal generation circuit 1404 ... Recording layer focus error signal generation circuit 1405 ... Servo layer focus error signal generation circuit 1501 ... System control circuit 1502 ... Recording layer focus control circuit 1503 ... Switch 1504 ... Recording layer focus drive voltage generation circuit 1505 ... Adder 1506 ... Servo layer focus control circuit 1507 ... Switch 1508: Servo layer focus drive voltage generation circuit 1509 ... Adder 1510 ... Servo layer tracking control circuit 1511 ... Switch 1512 ... Selector 1513 ... Selector 1514 ... Recording layer track pitch adjustment voltage generation circuit 1515 ... Adder 1516 ... Recording layer tracking control circuit 1517 ... Switch 1518 ... Selector 1519 ... Tracking drive voltage generation circuit 1520 ... Adder 1521 ... Slider control circuit 1522 ... Spindle control circuit 1523 ... Recording layer MainTE signal monitor circuit
221 Optical disk recording / playback device
222 Optical disc
500 light spot
501 light spot
502 Light spot
511 Light spot
1101 Front SUB tracking error signal generation means
1102 Main tracking error signal generation means
1103 Post SUB tracking error signal generation means
1104 Tracking error signal selection means 331 ... optical disk 332 ... optical pickup 333 ... signal processing circuit 334 ... spindle motor 335 ... servo error signal generation circuit 336 ... recording / reproduction signal processing circuit 338 ... actuator drive circuit 339 ... relay lens drive circuit 340 ... aberration Correction element drive circuit 341 ... Grating 342 ... Optical axis angle variable element drive circuit 1202 ... Laser diode 1209 ... Aberration correction element 1211 ... Objective lens 1212 ... Actuator 1221 ... Relay lens 1227 ... Variable angle rising mirror 1228 ... Actuator 2301 ... System control Circuit 2310 ... Tracking control circuit 2312 ... Relative position control circuit

Claims (37)

  1. 　膜厚方向に積層された１もしくは複数の記録層とを含む光ディスクに対して情報の記録を行なう光ディスク装置であって、
    　前記記録層に第１のレーザスポットと第２のレーザスポットを照射する光学系を備え、
    　前記第１のレーザスポットを用いてトラッキングを行いながら前記第２のレーザスポットを用いてマークを形成して情報の記録を行う場合に、前記記録層に形成されるマーク列の半径方向の間隔を調整するトラックピッチ調整を行うことを特徴とする光ディスク装置。     An optical disc apparatus for recording information on an optical disc including one or a plurality of recording layers stacked in a film thickness direction,
    An optical system for irradiating the recording layer with a first laser spot and a second laser spot;
    When recording information by forming marks using the second laser spot while performing tracking using the first laser spot, the distance between the mark rows formed in the recording layer in the radial direction is set. An optical disk apparatus for adjusting a track pitch to be adjusted.
  2. 　請求項１に記載の光ディスク装置であって、
    　前記第１のレーザスポットを用いてトラッキングを行う第１トラッキング制御部を備え、
    　前記第１トラッキング制御部中の所定の信号に対して所定のオフセットを加算することで前記記録層に形成されるマーク列の半径方向の間隔を調整することを特徴とする光ディスク装置。     The optical disc apparatus according to claim 1,
    A first tracking control unit that performs tracking using the first laser spot;
    An optical disc apparatus characterized by adjusting a radial interval between mark rows formed on the recording layer by adding a predetermined offset to a predetermined signal in the first tracking control unit.
  3. 　請求項１に記載の光ディスク装置であって、
    　前記第１のレーザスポットの出力信号から第１のトラッキングエラー信号を生成する第１トラッキングエラー信号生成部と、
    　前記第１のトラッキングエラー信号を用いてトラッキングを行う第１トラッキング制御部を備え、
    　前記第１のトラッキングエラー信号に対して所定のオフセットを加算することで前記記録層に形成されるマーク列の半径方向の間隔を調整することを特徴とする光ディスク装置。     The optical disc apparatus according to claim 1,
    A first tracking error signal generation unit that generates a first tracking error signal from an output signal of the first laser spot;
    A first tracking control unit that performs tracking using the first tracking error signal;
    An optical disk apparatus, wherein a predetermined offset is added to the first tracking error signal to adjust a radial interval between mark rows formed on the recording layer.
  4. 　請求項１に記載の光ディスク装置であって、
    　前記第１のレーザスポットの出力信号から第１のトラッキングエラー信号を生成する第１トラッキングエラー信号生成部と、
    　前記第１のレーザスポットの出力信号から前記第１のレーザスポットから反射された総光量を示す総和信号を生成する総和信号生成部と、
    　前記第１のトラッキングエラー信号の振幅を前記総和信号で正規化し、第１の正規化トラッキングエラー信号として生成する第１正規化トラッキングエラー信号生成部と、
    　前記第１の正規化トラッキングエラー信号を用いてトラッキングを行う第１トラッキング制御部を備え、
    　前記第１の正規化トラッキングエラー信号に対して所定のオフセットを加算することで前記記録層に形成されるマーク列の半径方向の間隔を調整することを特徴とする光ディスク装置。     The optical disc apparatus according to claim 1,
    A first tracking error signal generation unit that generates a first tracking error signal from an output signal of the first laser spot;
    A sum signal generator that generates a sum signal indicating the total amount of light reflected from the first laser spot from the output signal of the first laser spot;
    A first normalized tracking error signal generating unit that normalizes the amplitude of the first tracking error signal with the sum signal and generates a first normalized tracking error signal;
    A first tracking control unit that performs tracking using the first normalized tracking error signal;
    An optical disc apparatus, wherein a predetermined offset is added to the first normalized tracking error signal to adjust a radial interval between mark rows formed on the recording layer.
  5. 　請求項１に記載の光ディスク装置であって、
    　前記第１のレーザスポットと前記第２のレーザスポットの半径方向の間隔を調整可能な光学素子を備え、
    　前記光学素子によって、記録層に形成されるマーク列の半径方向の間隔を調整することを特徴とする光ディスク装置。     The optical disc apparatus according to claim 1,
    An optical element capable of adjusting a radial distance between the first laser spot and the second laser spot;
    An optical disc apparatus characterized in that a radial interval between mark rows formed on a recording layer is adjusted by the optical element.
  6. 　請求項１に記載の光ディスク装置であって、
    　前記第２のレーザスポットから得られる信号を用いて前記トラックピッチ調整を行うことを特徴とする光ディスク装置。     The optical disc apparatus according to claim 1,
    An optical disc apparatus characterized in that the track pitch adjustment is performed using a signal obtained from the second laser spot.
  7. 　請求項１に記載の光ディスク装置であって、
    　前記第１のレーザスポットを用いてトラッキングを行う第１トラッキング制御部と、
    　所定オフセットを出力するオフセット出力部と
    　前記第１トラッキング制御部中の所定の信号に対して前記オフセット出力部の出力値を加算する加算器と、
    　前記第２のレーザスポットから第２のトラッキングエラー信号を生成する第２トラッキングエラー信号生成部を備え、
    　前記トラックピッチ調整は、前記第２トラッキングエラー信号の値が所定の値になるように前記所定オフセットを調整することを特徴とする光ディスク装置。     The optical disc apparatus according to claim 1,
    A first tracking control unit that performs tracking using the first laser spot;
    An offset output unit that outputs a predetermined offset; and an adder that adds an output value of the offset output unit to a predetermined signal in the first tracking control unit;
    A second tracking error signal generator for generating a second tracking error signal from the second laser spot;
    The optical disc apparatus characterized in that the track pitch adjustment adjusts the predetermined offset so that a value of the second tracking error signal becomes a predetermined value.
  8. 　請求項１に記載の光ディスク装置であって、
    　前記第１のレーザスポットを用いてトラッキングを行う第１トラッキング制御部と、
    　所定オフセットを出力するオフセット出力部と
    　前記第１トラッキング制御部中の所定の信号に対して前記オフセット出力部の出力値を加算する加算器と、
    　前記第２のレーザスポットから第２のトラッキングエラー信号を生成する第２トラッキングエラー信号生成部を備え、
    　前記トラックピッチ調整は、前記第２トラッキングエラー信号の値が基準電位になるように前記所定オフセットを調整することを特徴とする光ディスク装置。     The optical disc apparatus according to claim 1,
    A first tracking control unit that performs tracking using the first laser spot;
    An offset output unit that outputs a predetermined offset; and an adder that adds an output value of the offset output unit to a predetermined signal in the first tracking control unit;
    A second tracking error signal generator for generating a second tracking error signal from the second laser spot;
    In the optical disk apparatus, the track pitch adjustment adjusts the predetermined offset so that a value of the second tracking error signal becomes a reference potential.
  9. 　請求項１に記載の光ディスク装置であって、
    　前記第１のレーザスポットを用いてトラッキングを行う第１トラッキング制御部と、
    　所定オフセットを出力するオフセット出力部と
    　前記第１トラッキング制御部中の所定の信号に対して前記オフセット出力部の出力値を加算する加算器と、
    　前記第２のスポットから再生信号を生成する再生信号生成部を備え、
    　前記トラックピッチ調整は、前記再生信号の振幅が最大となるように前記所定オフセットを調整することを特徴とする光ディスク装置。     The optical disc apparatus according to claim 1,
    A first tracking control unit that performs tracking using the first laser spot;
    An offset output unit that outputs a predetermined offset; and an adder that adds an output value of the offset output unit to a predetermined signal in the first tracking control unit;
    A reproduction signal generator for generating a reproduction signal from the second spot;
    The optical disc apparatus characterized in that the track pitch adjustment adjusts the predetermined offset so that the amplitude of the reproduction signal is maximized.
  10. 　請求項１に記載の光ディスク装置であって、
    　前記トラックピッチ調整を実施した後に、前記第１のレーザスポットを用いてトラッキングを行いながら第２のスポットを用いてマークを形成して情報を記録する動作を行うことを特徴とする光ディスク装置。     The optical disc apparatus according to claim 1,
    An optical disc apparatus characterized in that, after performing the track pitch adjustment, an operation of recording information by forming a mark using a second spot while performing tracking using the first laser spot.
  11. 　請求項１に記載の光ディスク装置であって、
    　前記光ディスクは螺旋状又は同心円状のトラックが形成されたサーボ層と膜厚方向に積層された１もしくは複数の記録層とを含み、
    　前記光学系は前記サーボ層に第３のレーザスポットを照射し、
    　前記第１のレーザスポットと前記第２のレーザスポットの半径方向の距離が前記サーボ層のトラックの間隔の整数倍であり、
    　前記整数をＮとするとき、
    　前記光ディスクに対する初回記録時には、前記第３のレーザスポットを用いてトラッキングを行いながら（Ｎ＋１）トラック以上の記録を行うことを特徴とする光ディスク装置。     The optical disc apparatus according to claim 1,
    The optical disk includes a servo layer on which spiral or concentric tracks are formed and one or more recording layers stacked in the film thickness direction,
    The optical system irradiates the servo layer with a third laser spot,
    A radial distance between the first laser spot and the second laser spot is an integral multiple of a track interval of the servo layer;
    When the integer is N,
    An optical disc apparatus characterized by performing recording for (N + 1) tracks or more while performing tracking using the third laser spot at the time of initial recording on the optical disc.
  12. 　請求項１に記載の光ディスク装置であって、
    　前記光ディスクは螺旋状又は同心円状のトラックが形成されたサーボ層と膜厚方向に積層された１もしくは複数の記録層とを含み、
    　前記光学系は前記サーボ層に第３のレーザスポットを照射し、
    　前記第１のレーザスポットと前記第２のレーザスポットの半径方向の距離が前記サーボ層のトラックの間隔の半分であり、
    　前記光ディスクに対する初回記録時には、前記第３のレーザスポットを用いてトラッキングを行いながら２トラック以上の記録を行うことを特徴とする光ディスク装置。     The optical disc apparatus according to claim 1,
    The optical disk includes a servo layer on which spiral or concentric tracks are formed and one or more recording layers stacked in the film thickness direction,
    The optical system irradiates the servo layer with a third laser spot,
    The radial distance between the first laser spot and the second laser spot is half of the track spacing of the servo layer;
    2. An optical disc apparatus for recording two or more tracks while performing tracking using the third laser spot at the time of initial recording on the optical disc.
  13. 　請求項１に記載の光ディスク装置であって、
    　前記光ディスクは螺旋状又は同心円状のトラックが形成されたサーボ層と膜厚方向に積層された１もしくは複数の記録層とを含み、
    　前記光学系は前記サーボ層に第３のレーザスポットを照射し、
    　前記第１のレーザスポットと前記第２のレーザスポットの半径方向の距離が前記サーボ層のトラックの間隔の整数倍であり、
    　前記整数をＮとするとき、
    　前記光ディスクに対する初回記録時には、前記第３のレーザスポットを用いてトラッキングを行いながら（Ｎ＋１）トラック以上の記録を行い、
    　前記初回記録によって形成されたマーク列が存在する半径位置において前記トラックピッチ調整を行うことを特徴とする光ディスク装置。     The optical disc apparatus according to claim 1,
    The optical disk includes a servo layer on which spiral or concentric tracks are formed and one or more recording layers stacked in the film thickness direction,
    The optical system irradiates the servo layer with a third laser spot,
    A radial distance between the first laser spot and the second laser spot is an integral multiple of a track interval of the servo layer;
    When the integer is N,
    During the initial recording on the optical disc, recording is performed for (N + 1) tracks or more while performing tracking using the third laser spot,
    An optical disc apparatus characterized in that the track pitch adjustment is performed at a radial position where a mark row formed by the initial recording exists.
  14. 　螺旋状又は同心円状のトラックが形成されたサーボ層と膜厚方向に積層された複数の記録層とを含む光ディスクに対して、
    　第１のレーザ光と第２のレーザ光を記録層に照射して情報の記録もしくは再生を行う光ディスク装置であって、
    　前記光ディスクを所定の回転軸を中心に回転させる光ディスク回転部と、
    　第１のレーザ光及び第２のレーザ光及び第３のレーザ光を前記光ディスク上に集光させる対物レンズと、
    　前記対物レンズを駆動するアクチュエータと、
    　前記第１のレーザ光による反射光量に応じた電気信号を出力する第１の光検出部と、
    　前記第１の光検出部の出力信号から前記記録層に対する第１のトラッキングエラー信号を生成する第１トラッキングエラー信号生成部と、
    　前記第１のトラッキングエラー信号に応じて前記アクチュエータを駆動してトラッキング制御を行う第１トラッキング制御部とを備え、
    　前記第１トラッキング制御部によってトラッキング制御を行いながら前記第２のレーザ光を用いて前記記録層にマークを形成して情報の記録を行う動作を行うより前に、
    　前記記録層に形成されるマーク列の半径方向の間隔を調整するトラックピッチ調整を行うことを特徴とする光ディスク装置。     For an optical disc that includes a servo layer in which spiral or concentric tracks are formed and a plurality of recording layers stacked in the film thickness direction,
    An optical disc apparatus for recording or reproducing information by irradiating a recording layer with a first laser beam and a second laser beam,
    An optical disk rotating section for rotating the optical disk about a predetermined rotation axis;
    An objective lens for condensing the first laser beam, the second laser beam, and the third laser beam on the optical disc;
    An actuator for driving the objective lens;
    A first light detection unit that outputs an electrical signal corresponding to the amount of light reflected by the first laser beam;
    A first tracking error signal generation unit that generates a first tracking error signal for the recording layer from an output signal of the first light detection unit;
    A first tracking control unit that performs tracking control by driving the actuator according to the first tracking error signal;
    Before performing information recording by forming a mark on the recording layer using the second laser beam while performing tracking control by the first tracking control unit,
    An optical disc apparatus characterized by performing a track pitch adjustment for adjusting a radial interval between mark rows formed on the recording layer.
  15. 　トラックを有する少なくとも一つのガイド層と、トラック構造を有さない少なくとも一つの記録層とを有する光ディスクに記録を行う光ディスク記録再生装置において、
    　　前記ガイド層に第一のレーザ光の焦点を合わせる第１の光学系と、
    　　前記記録層に、複数に分割された第二のレーザ光の焦点を合わせる第二の光学系と、
    　　前記第二のレーザ光の信号から複数のトラッキング誤差信号を生成するトラッキング誤差信号生成手段と、
    　　前記トラッキング誤差信号から制御を行う信号を選択するトラッキング誤差信号選択手段と、
    　　を備え、
    　　前記記録層に最適な記録パワーで記録を行うためのＯＰＣ（Optimum Power Control）処理を行った後に、未記録のＯＰＣ領域に記録マークを形成する事を特徴とする
    　　光ディスク記録再生装置。     In an optical disc recording / reproducing apparatus for recording on an optical disc having at least one guide layer having a track and at least one recording layer not having a track structure,
    A first optical system for focusing the first laser beam on the guide layer;
    A second optical system for focusing the second laser beam divided into a plurality of parts on the recording layer;
    Tracking error signal generating means for generating a plurality of tracking error signals from the second laser light signal;
    Tracking error signal selection means for selecting a signal to be controlled from the tracking error signal;
    With
    An optical disc recording / reproducing apparatus, wherein a recording mark is formed in an unrecorded OPC area after performing an OPC (Optimum Power Control) process for performing recording with an optimum recording power on the recording layer.
  16. 　前記記録マークは前記第二のレーザ光の分割数以下のトラック毎に記録されることを特徴とする請求項１５に記載の光ディスク記録再生装置。 16. The optical disc recording / reproducing apparatus according to claim 15, wherein the recording mark is recorded for each track equal to or less than the number of divisions of the second laser beam.
  17. 　前記記録マークは、連続する前記第二のレーザ光の分割数のトラックの間に少なくとも１つ以上記録される事を特徴とする請求項１５に記載の光ディスク記録再生装置。 16. The optical disc recording / reproducing apparatus according to claim 15, wherein at least one recording mark is recorded between a plurality of continuous tracks divided by the second laser beam.
  18. 　前記記録マークは、データ領域に記録されるマーク長とは異なるマーク長であることを特徴とする請求項１５に記載の光ディスク記録再生装置。 The optical disc recording / reproducing apparatus according to claim 15, wherein the recording mark has a mark length different from a mark length recorded in the data area.
  19. 　前記記録マークは、前記記録層毎で違うパターンである事を特徴とする請求項１５に記載の光ディスク記録再生装置。 16. The optical disc recording / reproducing apparatus according to claim 15, wherein the recording mark has a different pattern for each recording layer.
  20. 　前記記録マーク間の未記録領域の幅は、前記OPC処理で使用する領域の幅の整数倍である事を特徴とする請求項１５に記載の光ディスク記録再生装置。 16. The optical disc recording / reproducing apparatus according to claim 15, wherein the width of the unrecorded area between the recording marks is an integral multiple of the width of the area used in the OPC process.
  21. 　前記記録のタイミングは、ＯＰＣ処理の直後である事を特徴とする請求項１５に記載の光ディスク記録再生装置。 16. The optical disc recording / reproducing apparatus according to claim 15, wherein the recording timing is immediately after the OPC process.
  22. 　　トラックを有する少なくとも一つのガイド層と、トラック構造を有さない少なくとも一つの記録層とを有し、前記OPC領域に既に記録マークが形成されている光ディスクに記録を行う光ディスク記録再生装置であって、
    　　前記光ディスクのガイド層に第一のレーザ光の焦点を合わせる第一の光学系と、
    　　前記光ディスクの記録層に第二のレーザ光の焦点を合わせる第二の光学系と、
    　　前記第二のレーザ光の信号から複数のトラッキング誤差信号を生成するトラッキング誤差信号生成手段と、
    　　前記トラッキング誤差信号から、制御を行う信号を選択するトラッキング誤差信号選択手段と、
    　　を備え
    　　前記記録層に焦点を合わせる第二のレーザ光は、記録再生用の焦点とトラックキング用の焦点の少なくとも２つの焦点を有しており、
    　　前記記録マークにてトラック追従を行わせてＯＰＣ処理を行う光ディスク記録再生装置。     An optical disc recording / reproducing apparatus for performing recording on an optical disc having a recording mark already formed in the OPC area, wherein the optical disc has at least one guide layer having a track and at least one recording layer not having a track structure. ,
    A first optical system for focusing the first laser beam on the guide layer of the optical disc;
    A second optical system for focusing the second laser beam on the recording layer of the optical disc;
    Tracking error signal generating means for generating a plurality of tracking error signals from the second laser light signal;
    Tracking error signal selection means for selecting a signal to be controlled from the tracking error signal;
    The second laser beam focused on the recording layer has at least two focal points: a recording / reproducing focal point and a track king focal point;
    An optical disc recording / reproducing apparatus that performs OPC processing by performing track following with the recording mark.
  23. 　トラックを有する少なくとも一つのガイド層と、トラック構造を有さない少なくとも一つの記録層とを有する光ディスクに情報を記録する記録再生方法であって、
    　　前記記録層に最適な記録パワーで記録を行うためのＯＰＣ（Optimum Power Control）処理を行うステップと、
    　前記ＯＰＣ処理後に、前記光ディスクのＯＰＣ領域に記録マークを形成するステップと、
    　前記ＯＰＣ処理で求められた最適な記録パワーでデータ領域に情報を記録するステップとを有する記録再生方法。     A recording / reproducing method for recording information on an optical disc having at least one guide layer having a track and at least one recording layer not having a track structure,
    Performing an OPC (Optimum Power Control) process for recording at an optimum recording power on the recording layer;
    Forming a recording mark in the OPC area of the optical disc after the OPC processing;
    And a step of recording information in the data area with the optimum recording power obtained by the OPC process.
  24. 　前記ＯＰＣ領域に、３トラック以下毎に前記記録マークを形成することを特徴とする請求項２３に記載の記録再生方法。 24. The recording / reproducing method according to claim 23, wherein the recording mark is formed every 3 tracks or less in the OPC area.
  25. 　前記ＯＰＣ領域に、連続する３トラックの間に少なくとも１つ以上の記録マークを形成する事を特徴とする請求項２３に記載の記録再生方法。 24. The recording / reproducing method according to claim 23, wherein at least one or more recording marks are formed in the OPC area between three consecutive tracks.
  26. 　前記ＯＰＣ領域に、データ領域に記録するマーク長とは違うマーク長の記録マークを形成する事を特徴とする請求項２３に記載の記録再生方法。 24. The recording / reproducing method according to claim 23, wherein a recording mark having a mark length different from that recorded in the data area is formed in the OPC area.
  27. 　記録層毎で違うパターンで前記ＯＰＣ領域に前記記録マークを形成する事を特徴とする請求項２３に記載の記録再生方法。 24. The recording / reproducing method according to claim 23, wherein the recording mark is formed in the OPC area with a different pattern for each recording layer.
  28. 　前記ＯＰＣ領域に記録するマーク間の未記録領域の幅が、OPC処理で使用する幅の整数倍になるように記録マークを形成する事を特徴とする請求項２３に記載の記録再生方法。 24. The recording / reproducing method according to claim 23, wherein the recording mark is formed so that a width of an unrecorded area between marks recorded in the OPC area is an integral multiple of a width used in an OPC process.
  29. トラックを有する少なくとも一つのガイド層と、トラック構造を有さない少なくとも一つの記録層とを有する光ディスクに対して記録及び再生を行う記録再生方法であって、
    　　前記ガイド層に第一のレーザ光の焦点を合わせるステップと、
    　　前記記録層に第二のレーザ光の焦点を合わせるステップと、
    　　前記記録層に最適な記録パワーで記録を行うためのＯＰＣ（Optimum Power Control）処理を行うステップと、
    　　前記ＯＰＣ処理を行った領域に記録を行うレーザ光の強度にて上書き記録を行うステップとを含む記録再生方法。     A recording / reproducing method for performing recording and reproduction on an optical disc having at least one guide layer having a track and at least one recording layer not having a track structure,
    Focusing the first laser beam on the guide layer;
    Focusing a second laser beam on the recording layer;
    Performing an OPC (Optimum Power Control) process for recording at an optimum recording power on the recording layer;
    And a step of performing overwriting with the intensity of the laser beam for recording in the area subjected to the OPC process.
  30. 　前記記録のマーク列は、ＯＰＣ処理で記録したマーク列と同一である事を特徴とする、請求項２９に記載の記録再生方法。 30. The recording / reproducing method according to claim 29, wherein the mark mark of the recording is the same as the mark string recorded by the OPC process.
  31. 　前記上書き記録のレーザ光の強度が、ＯＰＣ処理時に出力したレーザ光の強度に反比例するように上書き記録のレーザ光の強度を変化させる事を特徴とする、請求項２９に記載の記録再生方法。 30. The recording / reproducing method according to claim 29, wherein the intensity of the laser beam for overwriting recording is changed so that the intensity of the laser beam for overwriting recording is inversely proportional to the intensity of the laser beam output during the OPC process.
  32. 　トラックを有する少なくとも一つのサーボ層と、トラックを有さない少なくとも一つの記録層と、を有する光ディスクの記録又は再生を行う光ディスク装置において、
    　前記光ディスクの前記サーボ層にレーザ光を照射する第１のレーザ光源と、
    　前記光ディスクの前記記録層にレーザ光を照射する第２のレーザ光源と、
    　前記第１のレーザ光源と前記第２のレーザ光源から出射されるレーザ光を集光する対物レンズと、
    　前記第１のレーザ光源により出射される第１のレーザ光の収束と発散を制御するリレーレンズと、
    　前記リレーレンズを駆動する第１のアクチュエータと、
    　前記対物レンズを駆動する第２のアクチュエータと、
    　前記第１のアクチュエータを制御する第１の制御部と、
    　前記第２のアクチュエータを制御する第２の制御部と、を備え、
    　前記第１のレーザ光源から出射され、前記対物レンズにより前記サーボ層に集光された第１の光スポットの前記光ディスク面に垂直な方向の位置制御を、前記第１のアクチュエータにより前記リレーレンズを駆動することによって実行し、
    　前記第１の光スポットの前記光ディスク面の半径方向への位置制御を、前記第２のアクチュエータにより前記対物レンズを駆動することにより実行し、
    　第２のレーザ光源から照射され、前記対物レンズにより前記記録層に集光された第２の光スポットの前記光ディスク面に垂直な方向への位置制御を、前記第２のアクチュエータにより前記対物レンズを駆動することで実行し、
    　前記第２の光スポットの前記光ディスク面の半径方向への位置制御を、前記第１のアクチュエータにより前記リレーレンズを駆動することにより実行することを特徴とする光ディスク装置。     In an optical disc apparatus for recording or reproducing an optical disc having at least one servo layer having a track and at least one recording layer not having a track,
    A first laser light source for irradiating the servo layer of the optical disc with laser light;
    A second laser light source for irradiating the recording layer of the optical disc with laser light;
    An objective lens for condensing laser light emitted from the first laser light source and the second laser light source;
    A relay lens for controlling convergence and divergence of the first laser beam emitted from the first laser light source;
    A first actuator for driving the relay lens;
    A second actuator for driving the objective lens;
    A first control unit for controlling the first actuator;
    A second control unit for controlling the second actuator,
    Position control of the first light spot emitted from the first laser light source and condensed on the servo layer by the objective lens in a direction perpendicular to the optical disc surface is performed, and the relay lens is operated by the first actuator. Run by driving,
    Controlling the position of the first light spot in the radial direction of the optical disc surface by driving the objective lens by the second actuator;
    Position control of the second light spot irradiated from the second laser light source and condensed on the recording layer by the objective lens in a direction perpendicular to the optical disk surface is performed by the second actuator. Run by driving,
    An optical disc apparatus, wherein position control of the second light spot in the radial direction of the optical disc surface is executed by driving the relay lens by the first actuator.
  33. 　請求項１の光ディスク装置において、
    　前記第１の光スポットの位置を基準とし、前記基準からの前記第２の光スポットの位置変化を検出する相対位置検出部を備え、
    　前記光ディスクの前記記録層に情報の記録或いは再生を行う場合に、
    前記第１の光スポットを前記トラックに追従するようにトラッキング制御がなされているときに得られるトラッキングエラー信号と前記第２の光スポットを記録マークに照射されることで得られるトラッキングエラー信号との差分から前記第１の光スポットの基準位置に対する前記第２の光スポットの相対位置を前記相対位置検出部より検出し、検出された相対位置に基づいて、前記リレーレンズを前記第１のアクチュエータにより駆動することで、前記記録層の記録マークに前記第２の光スポットを追従させながら記録或いは再生を行うことを特徴とする光ディスク装置。     The optical disk apparatus according to claim 1, wherein
    A relative position detection unit configured to detect a change in position of the second light spot from the reference with the position of the first light spot as a reference;
    When recording or reproducing information on the recording layer of the optical disc,
    A tracking error signal obtained when tracking control is performed so that the first light spot follows the track, and a tracking error signal obtained by irradiating the recording mark with the second light spot. A relative position of the second light spot with respect to a reference position of the first light spot is detected from the difference by the relative position detection unit, and the relay lens is moved by the first actuator based on the detected relative position. An optical disc apparatus that performs recording or reproduction by driving the recording mark on the recording layer while following the second light spot.
  34. 　請求項３３に記載の光ディスク装置において、
    　前記第２のレーザ光源から出射されたレーザ光を２つ以上のビームに分割するグレーティングを備え、
    　前記光ディスクの前記記録層に情報の記録を行う場合に、
    　　　　前記第２のレーザ光源から出射されたレーザ光を前記グレーティングにより０次回折光と±１次回折光に分割し、前記対物レンズにより前記記録層に前記０次回折光の光スポットと前記±１次回折光の光スポットの３つの光スポットとして集光し、
    　　　前記前記０次回折光の光スポットにて記録マークを形成し、
    　　　前記相対位置検出部より前記第１の光スポットを基準位置とする前記±１次回折光の光スポットの相対位置を検出し、
    前記検出した位置に基づいて前記第１のアクチュエータにより前記光ディスク面の半径方向に前記リレーレンズを駆動することで前記±１次回折光の光スポットの前記光ディスク面の半径方向の位置制御を行うことを特徴とする光ディスク装置。     34. The optical disc apparatus according to claim 33,
    A grating that splits the laser light emitted from the second laser light source into two or more beams;
    When recording information on the recording layer of the optical disc,
    The laser light emitted from the second laser light source is divided into 0th-order diffracted light and ± 1st-order diffracted light by the grating, and the objective lens is used to divide the light spot of the 0th-order diffracted light and the ± 1st-order diffracted light into the recording layer. Focused as three light spots of the light spot,
    Forming a recording mark with the light spot of the zero-order diffracted light;
    Detecting the relative position of the light spot of the ± first-order diffracted light with the first light spot as a reference position from the relative position detector;
    Based on the detected position, the first actuator drives the relay lens in the radial direction of the optical disk surface, thereby performing radial position control of the optical spot of the ± first-order diffracted light on the optical disk surface. An optical disc device characterized.
  35. 　トラックを有する少なくとも１つのサーボ層と、トラックを有さない少なくとも一つの記録層とを有する光ディスクに記録を行う光ディスク装置において、
    　前記光ディスクの前記サーボ層にレーザ光を照射する第１のレーザ光源と、
    　前記光ディスクの前記記録層にレーザ光を照射する第２のレーザ光源と、
    　前記第１のレーザ光源と前記第２のレーザ光源から出射されるレーザ光を集光する対物レンズと、
    　前記第１のレーザ光源により出射される第１のレーザ光の収束と発散を制御するリレーレンズと、
    　前記リレーレンズを駆動する第１のアクチュエータと、
    　前記対物レンズを駆動する第２のアクチュエータと、
    前記対物レンズから前記光ディスクに入射する前記第１、第２のレーザ光源から出射されるレーザ光の少なくとも一方の光ビームの光軸方向を変える光軸角度可変素子と、
    　前記第１のアクチュエータを制御する第１の制御部と、
    　前記第２のアクチュエータを制御する第２の制御部と、を備え、
    　　第１のレーザ光源から出射され、前記対物レンズにより前記サーボ層に集光した第１の光スポットの、前記光ディスク面に垂直な方向への位置制御を、前記第１のアクチュエータにより前記リレーレンズを駆動することで実行し、
    　前記第１の光スポットの前記光ディスク面の半径方向への位置制御を、前記第２のアクチュエータにより前記対物レンズを駆動することにより実行し、
    　第２のレーザ光源から出射され、前記対物レンズにより前記記録層に集光した第２の光スポットの前記光ディスク面に垂直な方向への位置制御を、前記第２のアクチュエータにより前記対物レンズを駆動することで実行し、
    　前記第２の光スポットの前記光ディスク面の半径方向への位置制御を前記光軸角度可変素子を駆動することで実行する、ことを特徴とする光ディスク装置。     In an optical disc apparatus for recording on an optical disc having at least one servo layer having a track and at least one recording layer not having a track,
    A first laser light source for irradiating the servo layer of the optical disc with laser light;
    A second laser light source for irradiating the recording layer of the optical disc with laser light;
    An objective lens for condensing laser light emitted from the first laser light source and the second laser light source;
    A relay lens for controlling convergence and divergence of the first laser beam emitted from the first laser light source;
    A first actuator for driving the relay lens;
    A second actuator for driving the objective lens;
    An optical axis angle variable element that changes the optical axis direction of at least one of the laser beams emitted from the first and second laser light sources incident on the optical disc from the objective lens;
    A first control unit for controlling the first actuator;
    A second control unit for controlling the second actuator,
    Position control of the first light spot emitted from the first laser light source and condensed on the servo layer by the objective lens in the direction perpendicular to the optical disk surface is performed by the first actuator. Run by driving,
    Controlling the position of the first light spot in the radial direction of the optical disc surface by driving the objective lens by the second actuator;
    Position control of the second light spot emitted from the second laser light source and condensed on the recording layer by the objective lens in a direction perpendicular to the optical disc surface is driven by the second actuator. To run and
    An optical disc apparatus, wherein position control of the second light spot in the radial direction of the optical disc surface is executed by driving the optical axis angle variable element.
  36. 　請求項３５に記載の光ディスク装置において、
    　前記第１の光スポットの位置を基準とし、前記基準からの前記第２の光スポットの位置変化を検出する相対位置検出部を備え、
    　　前記光ディスクの前記記録層に情報の記録を行う場合に、
    　　　前記第１の光スポットを前記トラックに追従するようにトラッキング制御がなされているときに得られるトラッキングエラー信号と前記第２の光スポットを記録マークに照射されることで得られるトラッキングエラー信号との差分から前記第２の光スポットを基準位置に対する前記第２の光スポットの相対位置を前記相対位置検出部より検出し、検出した相対位置に基づいて、前記光軸角度可変素子を制御することを特徴とする光ディスク装置。     36. The optical disc apparatus according to claim 35, wherein
    A relative position detection unit configured to detect a change in position of the second light spot from the reference with the position of the first light spot as a reference;
    When recording information on the recording layer of the optical disc,
    A tracking error signal obtained when tracking control is performed so that the first light spot follows the track, and a tracking error signal obtained by irradiating the recording mark with the second light spot. From the difference, the relative position of the second light spot with respect to a reference position is detected from the relative position detection unit, and the optical axis angle variable element is controlled based on the detected relative position. An optical disc device characterized.
  37. 　　請求項３６に記載の光ディスク装置において、
    　　前記第２のレーザ光源から出射されたレーザ光を２つ以上のビームに分割するグレーティングを備え、
    　　前記第２のレーザ光源から出射されたレーザ光を前記グレーティングにより０次回折光と±１次回折光に分割し、前記対物レンズにより前記記録層に前記０次回折光の光スポットと前記±１次回折光の光スポットの３つの光スポットとして集光し、
    　前記前記０次回折光の光スポットにて記録マークを形成し、
    　前記相対位置検出部より前記第１の光スポットの位置を基準とする前記±１次回折光の光スポットの相対位置を検出し、
    　前記検出した位置に基づいて前記光軸角度可変素子を制御することで前記±１次回折光の光スポットの前記光ディスク面の半径方向の位置制御を行うことを特徴とする光ディスク装置。     37. The optical disc apparatus according to claim 36,
    A grating that splits the laser light emitted from the second laser light source into two or more beams;
    The laser light emitted from the second laser light source is divided into 0th-order diffracted light and ± 1st-order diffracted light by the grating, and the objective lens is used to divide the light spot of the 0th-order diffracted light and the ± 1st-order diffracted light into the recording layer. Focused as three light spots of the light spot,
    Forming a recording mark with the light spot of the zero-order diffracted light;
    Detecting the relative position of the light spot of the ± 1st-order diffracted light with respect to the position of the first light spot from the relative position detector;
    An optical disc apparatus, wherein the optical axis angle variable element is controlled based on the detected position to control the radial position of the optical spot of the ± first-order diffracted light in the radial direction of the optical disc surface.
PCT/JP2012/074615 2012-01-27 2012-09-26 Optical disk device WO2013111382A1 (en)

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JP2012049918A JP2013186915A (en) 2012-03-07 2012-03-07 Optical disk recording and playback device and recording and playback method
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