JPS61216126A - Optical recording system - Google Patents
Optical recording systemInfo
- Publication number
- JPS61216126A JPS61216126A JP60055832A JP5583285A JPS61216126A JP S61216126 A JPS61216126 A JP S61216126A JP 60055832 A JP60055832 A JP 60055832A JP 5583285 A JP5583285 A JP 5583285A JP S61216126 A JPS61216126 A JP S61216126A
- Authority
- JP
- Japan
- Prior art keywords
- pulse
- signal
- waveform
- laser output
- recording
- Prior art date
- Legal status (The legal status 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 status listed.)
- Granted
Links
Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B20/00—Signal processing not specific to the method of recording or reproducing; Circuits therefor
- G11B20/10—Digital recording or reproducing
- G11B20/14—Digital recording or reproducing using self-clocking codes
- G11B20/1403—Digital recording or reproducing using self-clocking codes characterised by the use of two levels
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B11/00—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor
- G11B11/10—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor using recording by magnetic means or other means for magnetisation or demagnetisation of a record carrier, e.g. light induced spin magnetisation; Demagnetisation by thermal or stress means in the presence or not of an orienting magnetic field
- G11B11/105—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor using recording by magnetic means or other means for magnetisation or demagnetisation of a record carrier, e.g. light induced spin magnetisation; Demagnetisation by thermal or stress means in the presence or not of an orienting magnetic field using a beam of light or a magnetic field for recording by change of magnetisation and a beam of light for reproducing, i.e. magneto-optical, e.g. light-induced thermomagnetic recording, spin magnetisation recording, Kerr or Faraday effect reproducing
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B11/00—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor
- G11B11/10—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor using recording by magnetic means or other means for magnetisation or demagnetisation of a record carrier, e.g. light induced spin magnetisation; Demagnetisation by thermal or stress means in the presence or not of an orienting magnetic field
- G11B11/105—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor using recording by magnetic means or other means for magnetisation or demagnetisation of a record carrier, e.g. light induced spin magnetisation; Demagnetisation by thermal or stress means in the presence or not of an orienting magnetic field using a beam of light or a magnetic field for recording by change of magnetisation and a beam of light for reproducing, i.e. magneto-optical, e.g. light-induced thermomagnetic recording, spin magnetisation recording, Kerr or Faraday effect reproducing
- G11B11/10502—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor using recording by magnetic means or other means for magnetisation or demagnetisation of a record carrier, e.g. light induced spin magnetisation; Demagnetisation by thermal or stress means in the presence or not of an orienting magnetic field using a beam of light or a magnetic field for recording by change of magnetisation and a beam of light for reproducing, i.e. magneto-optical, e.g. light-induced thermomagnetic recording, spin magnetisation recording, Kerr or Faraday effect reproducing characterised by the transducing operation to be executed
- G11B11/10504—Recording
- G11B11/10506—Recording by modulating only the light beam of the transducer
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B11/00—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor
- G11B11/10—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor using recording by magnetic means or other means for magnetisation or demagnetisation of a record carrier, e.g. light induced spin magnetisation; Demagnetisation by thermal or stress means in the presence or not of an orienting magnetic field
- G11B11/105—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor using recording by magnetic means or other means for magnetisation or demagnetisation of a record carrier, e.g. light induced spin magnetisation; Demagnetisation by thermal or stress means in the presence or not of an orienting magnetic field using a beam of light or a magnetic field for recording by change of magnetisation and a beam of light for reproducing, i.e. magneto-optical, e.g. light-induced thermomagnetic recording, spin magnetisation recording, Kerr or Faraday effect reproducing
- G11B11/10502—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor using recording by magnetic means or other means for magnetisation or demagnetisation of a record carrier, e.g. light induced spin magnetisation; Demagnetisation by thermal or stress means in the presence or not of an orienting magnetic field using a beam of light or a magnetic field for recording by change of magnetisation and a beam of light for reproducing, i.e. magneto-optical, e.g. light-induced thermomagnetic recording, spin magnetisation recording, Kerr or Faraday effect reproducing characterised by the transducing operation to be executed
- G11B11/10515—Reproducing
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B11/00—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor
- G11B11/10—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor using recording by magnetic means or other means for magnetisation or demagnetisation of a record carrier, e.g. light induced spin magnetisation; Demagnetisation by thermal or stress means in the presence or not of an orienting magnetic field
- G11B11/105—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor using recording by magnetic means or other means for magnetisation or demagnetisation of a record carrier, e.g. light induced spin magnetisation; Demagnetisation by thermal or stress means in the presence or not of an orienting magnetic field using a beam of light or a magnetic field for recording by change of magnetisation and a beam of light for reproducing, i.e. magneto-optical, e.g. light-induced thermomagnetic recording, spin magnetisation recording, Kerr or Faraday effect reproducing
- G11B11/10502—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor using recording by magnetic means or other means for magnetisation or demagnetisation of a record carrier, e.g. light induced spin magnetisation; Demagnetisation by thermal or stress means in the presence or not of an orienting magnetic field using a beam of light or a magnetic field for recording by change of magnetisation and a beam of light for reproducing, i.e. magneto-optical, e.g. light-induced thermomagnetic recording, spin magnetisation recording, Kerr or Faraday effect reproducing characterised by the transducing operation to be executed
- G11B11/1053—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor using recording by magnetic means or other means for magnetisation or demagnetisation of a record carrier, e.g. light induced spin magnetisation; Demagnetisation by thermal or stress means in the presence or not of an orienting magnetic field using a beam of light or a magnetic field for recording by change of magnetisation and a beam of light for reproducing, i.e. magneto-optical, e.g. light-induced thermomagnetic recording, spin magnetisation recording, Kerr or Faraday effect reproducing characterised by the transducing operation to be executed to compensate for the magnetic domain drift or time shift
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B20/00—Signal processing not specific to the method of recording or reproducing; Circuits therefor
- G11B20/10—Digital recording or reproducing
- G11B20/10009—Improvement or modification of read or write signals
-
- 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
- G11B7/125—Optical beam sources therefor, e.g. laser control circuitry specially adapted for optical storage devices; Modulators, e.g. means for controlling the size or intensity of optical spots or optical traces
- G11B7/126—Circuits, methods or arrangements for laser control or stabilisation
-
- 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
- G11B7/2407—Tracks or pits; Shape, structure or physical properties thereof
- G11B7/24085—Pits
Landscapes
- Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Signal Processing For Digital Recording And Reproducing (AREA)
- Optical Recording Or Reproduction (AREA)
Abstract
Description
【発明の詳細な説明】
〔発明の利用分野〕
本発明はデータの光学的記録方式に係り、特にパルスの
立ち上り、立下がりをデータとする変調信号を光ディス
ク等の記録媒体に記録するのに好適な記録方式に関する
。[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to an optical data recording system, and is particularly suitable for recording a modulated signal whose data is the rise and fall of a pulse on a recording medium such as an optical disk. Regarding recording methods.
従来、パルスの立ち上がり、立ち下がり、をデータとす
る変調信号、例えば、NPZIコードのような信号を光
ディスク等の記録媒体に記録する場合、変調信号そのも
のでレーザ光の強度を変調していた。つまり、入力信号
コードのロジックの立ち上がり、立ち下がりでレーザ出
力のスイッチングを行なっていた。Conventionally, when a modulated signal that uses the rising and falling edges of a pulse as data, such as a signal such as an NPZI code, is recorded on a recording medium such as an optical disk, the intensity of a laser beam is modulated by the modulating signal itself. In other words, the laser output was switched according to the logic rise and fall of the input signal code.
しかし、この方法では、特に光ディスクのように熱的な
性質を利用して信号を記録する場合には記録パルスによ
って形成されたピッ1〜の前縁、後縁にそれぞれ対応し
た再生信号の立ち」〕かり、立ち下がりの対称性が、記
録パルス幅の増加とともに劣化し、スライスレベルを通
して再生パルス幅から記録パルス幅を得る場合に、エラ
ーの原因となり、高い信頼性が得られないという欠点が
あった。However, with this method, especially when recording signals using thermal properties such as on an optical disc, the reproduction signal rises corresponding to the leading and trailing edges of the pips formed by the recording pulse. ] However, the symmetry of the falling edge deteriorates as the recording pulse width increases, causing errors when obtaining the recording pulse width from the reproduction pulse width through the slice level, making it difficult to obtain high reliability. Ta.
本発明の目的は、上記従来の欠点を除去し、変調信号パ
ルスを適当なパルス波形に変えてレーザ出力を制御し、
立ち上がり、立ち下がりの対称性のよい再生波形が得ら
れるような、信頼性の高い光学的記録方式を提供するこ
とにある。The purpose of the present invention is to eliminate the above-mentioned conventional drawbacks, change the modulation signal pulse to an appropriate pulse waveform, and control the laser output.
The object of the present invention is to provide a highly reliable optical recording system that can obtain a reproduced waveform with good rise and fall symmetry.
光ディスクでは熱的な性質を利用して情報を記録してお
り、記録パルスの立ち上がり、立ち下がりにそれぞれ対
応する記録媒体上の点、すなわち記録パルスによって形
成されるピットあるいは磁化ドメインの前縁と後縁部分
の形成時における温度は、熱拡散の効果により後縁側の
方が前縁側よりも高くなる。そのために、ピットあるい
はドメインは後縁側に拡がった形状を示し、その再生波
形の立ち」二がりと立ち下がりの波形の対称性が悪くな
る。この傾向は記録パルス幅が長くなるにしたがって強
くなる。このような再生波形ではレベルスライサーに通
して記録パルス幅を検出しよう宋
としてもエラーの発生確場が高く、高い信頼性が得られ
ない。Optical disks record information using thermal properties, and the points on the recording medium that correspond to the rising and falling edges of the recording pulse, that is, the leading edge and trailing edge of the pit or magnetized domain formed by the recording pulse, are During the formation of the edge portion, the temperature on the trailing edge side is higher than on the leading edge side due to the effect of thermal diffusion. For this reason, the pit or domain exhibits a shape that expands toward the trailing edge side, and the symmetry of the waveform between the rising edge and the falling edge of the reproduced waveform becomes poor. This tendency becomes stronger as the recording pulse width becomes longer. Even if such a reproduced waveform is passed through a level slicer to detect the recording pulse width, there is a high probability that an error will occur, and high reliability cannot be obtained.
そこで、本発明では入力パルス幅変調信号の波形を熱拡
散の効果を考慮した波形に変換し、それをレーザ出力波
形として用いる事によって、立ち」二かり、立ち下がり
の対称性のよい再生波形が得られる信号(ピットあるい
は磁化ドメイン)を記録する。Therefore, in the present invention, by converting the waveform of the input pulse width modulation signal into a waveform that takes into account the effect of thermal diffusion and using it as the laser output waveform, a reproduced waveform with good symmetry of the rising edge and falling edge can be obtained. The resulting signal (pit or magnetized domain) is recorded.
以下、本発明を実施例によって詳細に説明する。 Hereinafter, the present invention will be explained in detail with reference to Examples.
:、3)
本発明の第1の実施例は、ピットあるいはドメイン形成
時において熱拡散の影響を強く受けるパルス幅の長い記
録パルスに対して、その前縁と後縁を短いパルス幅のパ
ルスでそれぞれ形成し、両パルスの間に時間間隔を設け
る事によって、後縁側への熱拡散の影響を軽減するもの
である。すなわち、第1図(B)に示すように、入力変
調信号5に対し、その前縁、後縁に対応してパルス7a
。:, 3) In the first embodiment of the present invention, the leading edge and the trailing edge of a recording pulse with a long pulse width, which is strongly affected by thermal diffusion during pit or domain formation, are replaced with pulses with a short pulse width. By forming both pulses and providing a time interval between both pulses, the influence of heat diffusion to the trailing edge side is reduced. That is, as shown in FIG. 1(B), pulses 7a are generated corresponding to the leading and trailing edges of the input modulated signal 5.
.
7bを作り、両パルスの間に時間間隔8を設けたパルス
列6のレーザ出力でピットあるいはドメインを形成する
のである。この場合、入力変調信号のパルス幅がさらに
長くなると、パルス列6のパルス間隔8が長くなり、再
生信号波形、%10のくぼみ11が大きくなる。そこで
第1図(C)に示すように、パルス間隔8の間にも、熱
拡散の影響を強く与えない程度のレーザ出力]2を与え
るようにする。あるいは第1図(D)に示すように、パ
ルス間隔8の間に、1個または数個のパルス16を挿入
したレーザ出力波形15を用いることもできる。7b, and the pits or domains are formed by the laser output of the pulse train 6 with a time interval 8 between both pulses. In this case, as the pulse width of the input modulation signal becomes longer, the pulse interval 8 of the pulse train 6 becomes longer, and the recess 11 of the reproduced signal waveform, %10, becomes larger. Therefore, as shown in FIG. 1(C), even during the pulse interval 8, a laser output [2] which does not strongly affect the thermal diffusion is applied. Alternatively, as shown in FIG. 1(D), a laser output waveform 15 in which one or several pulses 16 are inserted between pulse intervals 8 can also be used.
j また、第1図(A)に示す再生波形4
のような1 前縁、後縁の対称性よいものを形
成する、すなわち熱拡散の影響の小さいピットあるいは
ドメイン; 3を形成する短いパルス幅を持
った入力変調信号1 □9.対、−C4よ、
□。よよ。波形2ウーイ、、ヵ波形1 とし
、長い記録パルス幅を持った入力変調信号51
に対しては、(B)、(C)又は(D)に示したよ
うなレーザ出力波形6,12あるいは15を用いる。j Also, the reproduced waveform 4 shown in FIG. 1(A)
1 Forms leading and trailing edges with good symmetry, i.e. pits or domains with little influence of thermal diffusion; 3 Input modulation signal 1 with a short pulse width forms □9. vs. -C4,
□. Yoyo. The input modulation signal 51 has a long recording pulse width with waveform 2 and waveform 1.
For this, laser output waveforms 6, 12, or 15 as shown in (B), (C), or (D) are used.
第2の方式は、ピッ]〜あるいはドメインの形成(時に
おける後縁側への熱拡散を考慮して、第2図に示すよう
に、レーザ出力波形として、パルス高21をある時定数
で減衰させたもの2oを用いる1 事によって
、記録媒体のレーザ光照射部分を一様]
1 な温度分布にするものである。The second method is to attenuate the pulse height 21 with a certain time constant as the laser output waveform, as shown in Fig. By using the above-mentioned laser beam, the laser beam irradiated portion of the recording medium has a uniform temperature distribution.
次に、上記の第1の方式を実現するためのタイ1
ムチヤードの一例を第3図に示し・さらに3のりi
A%″′−8°”°″′″A″!ii″I
i刊591711 出力を得るための回路ブ
ロックの一例を第4図に1 示す。第4図に示
した回路は、2つの遅延回路45.4.6と、その遅延
時間を設定する回路44.4つの論理回路47,48,
49,50、入力記録パルスによって動作するカレン1
〜スイツチを備えた2つのパルス電流源51.5’2、
プリバイアス供給用のDC電流源53、電流加算回路5
4、及び半感体レーザ55で構成されている。Next, we will introduce tie 1 to realize the first method above.
An example of the whipyard is shown in Figure 3.
A%″′−8°”°″′″A″!ii″I
Figure 4 shows an example of a circuit block for obtaining an output. The circuit shown in FIG. 4 includes two delay circuits 45, 4, 6, a circuit 44 for setting the delay time, four logic circuits 47, 48,
49, 50, Karen 1 operated by input recording pulse
~ two pulsed current sources 51.5'2 with switches,
DC current source 53 for pre-bias supply, current addition circuit 5
4, and a semi-sensitive laser 55.
以下、第3.4図を用いてその動作を説明する。The operation will be explained below using FIG. 3.4.
遅延時間τ1.τ2を遅程時間設定回路44で設定し、
入力変調信号24を、設定回路44で指定された遅延時
間τ2.τ、+τ2の遅延回路45゜46それぞれに通
して、τ2遅遅延量25とτ1+τ2遅延信号26を得
る。次に入力変調信号24とτ1+τ2遅延信号26を
AND回路47、NAND回路48それぞれに通してロ
ジック信号27、ロジック信号28をそれぞれ得る。さ
らに、τ2遅遅延量25とロジック信号28をA N
l)回路49に通して、記録ロジック信号29を得る。Delay time τ1. τ2 is set by the delay time setting circuit 44,
The input modulation signal 24 is delayed by a delay time τ2.tau specified by the setting circuit 44. A τ2 delay amount 25 and a τ1+τ2 delay signal 26 are obtained by passing through delay circuits 45 and 46 for τ and +τ2, respectively. Next, the input modulation signal 24 and the τ1+τ2 delayed signal 26 are passed through an AND circuit 47 and a NAND circuit 48, respectively, to obtain a logic signal 27 and a logic signal 28, respectively. Furthermore, the τ2 delay amount 25 and the logic signal 28 are A N
l) Pass through circuit 49 to obtain recording logic signal 29;
また、ロジック信号27とτ2遅遅延量25をAND回
路50に通して記録ロジック信号30を得る。Furthermore, the recording logic signal 30 is obtained by passing the logic signal 27 and the τ2 delay amount 25 through an AND circuit 50.
記録ロジック信号29でパルス電流源52をスイツチン
グさせる事によって、記録ロジック信号29と同様の波
形のレーザ駆動電流を得る。さらに、記録ロジック信号
30でパルス電流源51をスイッチングさせ、電流加算
回路54に入力させる事によってレーザ出力31を得る
事ができる。By switching the pulse current source 52 using the recording logic signal 29, a laser drive current having a waveform similar to that of the recording logic signal 29 is obtained. Further, the laser output 31 can be obtained by switching the pulse current source 51 using the recording logic signal 30 and inputting it to the current adding circuit 54.
ただし、パルス電流源51.52のパルス電流値は外部
より個々に設定できるものとする。なお、半導体レーザ
は、該レーザからのレーザ出力を回転する光デイスク上
の記録膜に絞り込む光学系、光ディスクからの反射光を
検出する光検出系、光デイスク上でのレーザ光の位置調
整機構(焦点制御、トラッキング制御)からなる光ヘッ
ドに組込まれている。かかる光ヘッド、その移動機構等
からなる光デイスク装置全体の構成は、特開昭58−9
1536号に詳しく述べられている。However, it is assumed that the pulse current values of the pulse current sources 51 and 52 can be individually set from the outside. Note that a semiconductor laser requires an optical system that focuses the laser output from the laser onto a recording film on a rotating optical disk, a photodetection system that detects the reflected light from the optical disk, and a mechanism for adjusting the position of the laser beam on the optical disk. It is incorporated into an optical head consisting of focus control and tracking control. The overall structure of an optical disk device including such an optical head, its moving mechanism, etc. is disclosed in Japanese Patent Application Laid-Open No. 58-9.
No. 1536 describes this in detail.
第3図に示すように、本実施例では、入力変調信号24
として、4種数のパルス幅P1. P、、 P、。As shown in FIG. 3, in this embodiment, the input modulation signal 24
As, four kinds of pulse widths P1. P,, P,.
P4(ただしP、<P2<P3<P4)から構成される
可変調コード信号を用いた。ここで第1図(B)に示す
レーザ出力波形の前縁、後縁のパルス7a。A variable tone code signal consisting of P4 (P, <P2<P3<P4) was used. Here, pulses 7a at the leading and trailing edges of the laser output waveform shown in FIG. 1(B).
7bそれぞれのパルス幅τ4.τ2の設定条件は1、入
力可変長コード信号の最小くりかえしパルス周波数T、
□いに対し、
τ1≦’r++xw/2かつ、τ2≦Twy*/2であ
ること。7b each pulse width τ4. The setting conditions for τ2 are 1, the minimum repetition pulse frequency T of the input variable length code signal,
□In contrast, τ1≦'r++xw/2 and τ2≦Twy*/2.
第2図の例では、TWIN”2T1であり、τ1≦T1
かつ、τ2≦T1
であることを示す。In the example of FIG. 2, TWIN”2T1, and τ1≦T1
Moreover, it is shown that τ2≦T1.
2、設定した線速度(ディスク回転数と記録半径で決定
される)と記録パルスレーザ出力パワーに対して、
幅のレーザパルス出力で、第1図(A)に示すような前
縁、後縁の対称性のよい再生波形4が得られること。2. With respect to the set linear velocity (determined by the disk rotation speed and recording radius) and the recording pulse laser output power, the leading edge and trailing edge as shown in Figure 1 (A) are generated with the laser pulse output of the width. A reproduced waveform 4 with good symmetry can be obtained.
本実施例で用いた入力変調コード信号24のパルス幅P
工f Pal pat p4は、例えばP□= 150
(nsec)
P2= 200 (nsec)
P、 = 250 (nsec)
P4 = 300 (nsec)
であり、τ1とτ2の設定については、ここではτ三τ
1=で2とし、
設定条件1より
τ≦150 (’n5ec)
さらに設定条件2より
τ= 100 (nsec)とした。Pulse width P of input modulation code signal 24 used in this example
Engineering f Pal pat p4 is, for example, P□=150
(nsec) P2 = 200 (nsec) P, = 250 (nsec) P4 = 300 (nsec), and regarding the setting of τ1 and τ2, here τ3τ
1 = 2, and from setting condition 1, τ≦150 ('n5ec), and from setting condition 2, τ = 100 (nsec).
上記の設定によって得られたレーザ出力31について述
べる。The laser output 31 obtained with the above settings will be described.
2τ= 200 (nsec) (一般にはτ1+τ
2)以下のパルス幅P1= 150 (nsec) 、
P、 =200(nsec)の入力パルス33.34
に対しては、単にτ2だけ遅延されるだけで、波形は変
化しない記録パルス37.38がそれぞれ記録ロジック
信号として得られ、それぞれに対応したパルス41.4
2をレーザ出力する。2τ= 200 (nsec) (generally τ1+τ
2) The following pulse width P1 = 150 (nsec),
P, = 200 (nsec) input pulse 33.34
For the recording pulses 37 and 38, which are simply delayed by τ2 and whose waveforms do not change, are obtained as recording logic signals, and the corresponding pulses 41 and 4 are respectively obtained as recording logic signals.
2 is output as a laser.
一方、2τ(一般にはτ1+τ、)よりも長いパルス幅
P3= 250 [n5ec] 、P4= 300(n
sec)の入力パルス32.35に対しては、τ2遅延
さく9)
れるだけでなく、さらに前縁側、後縁側と共にパルス幅
τのパルス7a、7b (一般には前縁側のパルス幅が
τ1、後縁側がτ2のパルス列)と時間間隔8で構成さ
れた波形36.39が記録ロジック信号として得られる
。レーザ出力としては、パルス電流源51のパルス電流
レベルを変えることによって、時間間隔8の部分の出力
レベル可変なパルス形状40.43を得る。On the other hand, the pulse width P3 = 250 [n5ec], P4 = 300 (n
For an input pulse 32.35 of sec), not only is there a τ2 delay 9), but also pulses 7a and 7b with a pulse width τ on both the leading edge side and the trailing edge side (generally, the pulse width on the leading edge side is τ1, and the pulse width on the trailing edge side is Waveforms 36 and 39 each consisting of a pulse train whose edges are τ2) and a time interval of 8 are obtained as recording logic signals. As for the laser output, by changing the pulse current level of the pulse current source 51, a pulse shape 40.43 whose output level is variable in the time interval 8 portion is obtained.
得られたピット形状及び再生波形について述べる。The obtained pit shape and reproduced waveform will be described.
レーザ出力波形41.42に対しては、第1図(A)に
示したようなピット形状3、再生波形4を得た。For the laser output waveforms 41 and 42, a pit shape 3 and a reproduced waveform 4 as shown in FIG. 1(A) were obtained.
また、レーザ出力波形4Q、43については、パルス電
流源51の電流レベルをゼロに設定した場合には、第1
図(B)に示したようなピット形状9と再生信号10を
得た。一方、電流レベルを適切な有限の値を設定した場
合には、第1図(C)に示したようなピット形状]3と
再生波形14を得た。Regarding the laser output waveforms 4Q and 43, when the current level of the pulse current source 51 is set to zero, the first
A pit shape 9 and a reproduced signal 10 as shown in Figure (B) were obtained. On the other hand, when the current level was set to an appropriate finite value, a pit shape [3] and a reproduced waveform 14 as shown in FIG. 1(C) were obtained.
このように、入力可変長コード信号をそのままレーザ出
力した場合には、パルス幅が200 [n5ec]以上
のパルス32.35では、立ち上がり、立ち下がりの対
称性の悪い再生波形しか得られなかったのに対し、第4
図に示した回路に入力可変調コード信号を通してレーザ
出力することによって、第1図に示すような立ち上がり
、立ち下がりの対称性のよい再生波形を得ることができ
た。In this way, if the input variable length code signal was outputted as it was by the laser, only a reproduced waveform with poor symmetry of rising and falling edges could be obtained for pulses 32.35 with a pulse width of 200 [n5ec] or more. For the fourth
By passing the input variable tone code signal through the circuit shown in the figure and outputting it as a laser, it was possible to obtain a reproduced waveform with good rise and fall symmetry as shown in FIG.
第1の方式の実現例としては他に、入力変調信号を構成
する種々のパルス幅のパルスに対し、それぞれに対応す
るレーザ出力波形をROM (ReadOnly Me
mory )にあらかじめ記憶して置き、それらを入力
変調信号に同期させて出力させてもよい。Another example of implementing the first method is to store laser output waveforms corresponding to pulses of various pulse widths constituting the input modulation signal in a ROM (Read Only Me).
It is also possible to store them in advance in a memory (Mory) and output them in synchronization with the input modulation signal.
次に、第2の方式を実現するための回路ブロックの一例
を第5図に示す。Next, FIG. 5 shows an example of a circuit block for realizing the second method.
第5図の回路ブロックの構成について述べる。The configuration of the circuit block shown in FIG. 5 will be described.
56は微分回路57の時定数で3を設定する回路、58
は微分波形の正電圧の部分を取り出すレベルスライス回
路、59は入力パルスに対して設定した正電圧のパルス
を出力する電圧レベル設定回路、60は電圧加算回路、
61は電圧−電流変換回路、63はバイアス入力電流波
形に対応したレーザ駆動電流を出力するパルス電流源、
62はDCブリバイアス電流源、64は電流加算回路、
65は半導体レーザである。56 is a circuit that sets the time constant of the differentiating circuit 57 to 3; 58
59 is a voltage level setting circuit that outputs a positive voltage pulse set in response to an input pulse; 60 is a voltage adder circuit;
61 is a voltage-current conversion circuit; 63 is a pulse current source that outputs a laser drive current corresponding to the bias input current waveform;
62 is a DC bias current source, 64 is a current addition circuit,
65 is a semiconductor laser.
第6図に示した各回路の出力信号を用いて、第5図の回
路ブロックの動作を説明する。The operation of the circuit block shown in FIG. 5 will be explained using the output signals of each circuit shown in FIG.
入力変調信号24は、設定時定数で、の微分回路57で
微分され、微分出力波形48号66となる。The input modulation signal 24 is differentiated by the differentiating circuit 57 with a set time constant, resulting in a differentiated output waveform 48 and 66.
この信号66はレベルスライス回路で正電圧の部分だけ
取り出され、67のような波形の信号となる。この信号
67に、入力信号24に同期した正電圧パルス信号を加
えて、さらに電流変換してバイアス電流入力信号68を
得る。バイアス電流入力信号68をパルス電流源63に
人力して、電流入力変調信号として、第3図に示した可
変調コード信号24を用いた。時定数で3の設定条件と
して、
]、第2図に示したように、ピッ1−あるいはドメイン
の形成時における後縁側への熱拡散の効果を補償した減
衰の傾き21を与える時定数τ3にする。Only the positive voltage portion of this signal 66 is extracted by a level slice circuit, resulting in a signal with a waveform like 67. A positive voltage pulse signal synchronized with the input signal 24 is added to this signal 67, and further current conversion is performed to obtain a bias current input signal 68. A bias current input signal 68 was manually input to the pulse current source 63, and the variable tone code signal 24 shown in FIG. 3 was used as the current input modulation signal. As a setting condition for a time constant of 3, ], as shown in Fig. 2, the time constant τ3 is set to give a slope 21 of attenuation that compensates for the effect of heat diffusion toward the trailing edge during the formation of pitch 1- or domains. do.
本実施例では、設定した線速度、記録媒体」二での最大
照射レーザパワーに対して、τ、=300[n5ec]
と設定することにより、入力可変長コード信号24を構
成する4種のパルス幅の信号パルス32,33,34,
35それぞれに対し、第2図に示すような立ち上がり、
立ち下がりの対称性のよい再生波形23が得られた。In this example, for the set linear velocity and the maximum irradiation laser power at the recording medium 2, τ = 300 [n5ec]
By setting, the signal pulses 32, 33, 34, and 4 types of pulse widths constituting the input variable length code signal 24 are set as
For each of 35, the rise as shown in Figure 2,
A reproduced waveform 23 with good fall symmetry was obtained.
1 *□1oよゎ17.88□%)<)L/ユ。。 1 *□1oyoゎ17.88□%)<)L/Yu. .
−1つ。-One.
にそれぞれ対応した、再生波形の立ち上がり、立′1
ち下がりの対称性をよくすることができるので
、(パルスの立ち上がり、立ち下がりをデータとする1
□お、□オ8□第1o2□□、8.3、)
エラーを少なく、かつ、高い信頼性を得ることが1
’t−aa。The rise and rise of the reproduced waveform corresponding to
Since it is possible to improve the symmetry of the fall of the pulse,
□Oh, □O8□1st o2□□, 8.3,)
Reducing errors and achieving high reliability is 1.
't-aa.
第1図は本発明の第1の実施例を説明する図、第2図は
、本発明の第2の実施例を説明する図、第3図は、第1
の実施例を実施するための回路の動作を説明するための
タイムチャート、第4図は、本発明の第1の実施例を実
施するための回路構成を示すブロック図、第5図は、第
2の実施例を実施するための回路構成を示すブロック図
、第6図は、その入出力信号を示すタイムチャー1へで
ある。FIG. 1 is a diagram for explaining the first embodiment of the present invention, FIG. 2 is a diagram for explaining the second embodiment of the present invention, and FIG. 3 is a diagram for explaining the first embodiment of the present invention.
FIG. 4 is a block diagram showing the circuit configuration for implementing the first embodiment of the present invention, and FIG. 5 is a time chart for explaining the operation of the circuit for implementing the first embodiment of the present invention. FIG. 6 is a block diagram showing the circuit configuration for implementing the second embodiment, and is a time chart 1 showing the input/output signals thereof.
Claims (1)
に情報を記録する光学的記録方式において、該入力変調
信号のパルス波形をそのパルス幅に応じて変形して該レ
ーザ光の強度変調を行なうことを特徴とする光学的記録
方式。In an optical recording method that records information on a recording medium by modulating the intensity of a laser beam using an input modulation signal, the intensity of the laser beam is modulated by changing the pulse waveform of the input modulation signal according to its pulse width. An optical recording method characterized by:
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP60055832A JP2559362B2 (en) | 1985-03-22 | 1985-03-22 | Optical recording method |
US06/832,887 US4646103A (en) | 1985-03-20 | 1986-02-26 | Optical recording method |
NL8600690A NL8600690A (en) | 1985-03-20 | 1986-03-18 | OPTICAL REGISTRATION METHOD. |
DE19863609068 DE3609068A1 (en) | 1985-03-20 | 1986-03-18 | OPTICAL RECORDING PROCEDURE |
DE3644937A DE3644937C2 (en) | 1985-03-20 | 1986-03-18 |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP60055832A JP2559362B2 (en) | 1985-03-22 | 1985-03-22 | Optical recording method |
Related Child Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP4063303A Division JP2546100B2 (en) | 1992-03-19 | 1992-03-19 | Optical information recording method |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS61216126A true JPS61216126A (en) | 1986-09-25 |
JP2559362B2 JP2559362B2 (en) | 1996-12-04 |
Family
ID=13009946
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP60055832A Expired - Lifetime JP2559362B2 (en) | 1985-03-20 | 1985-03-22 | Optical recording method |
Country Status (1)
Country | Link |
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JP (1) | JP2559362B2 (en) |
Cited By (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS61237233A (en) * | 1985-04-15 | 1986-10-22 | Mitsubishi Electric Corp | Signal recording device |
JPS63153726A (en) * | 1986-10-29 | 1988-06-27 | コーニンクレッカ フィリップス エレクトロニクス エヌ ヴィ | Method and apparatus for recording binary information signal |
JPS63160017A (en) * | 1986-12-23 | 1988-07-02 | Yamaha Corp | Optical disk recorder |
JPS63269321A (en) * | 1987-04-28 | 1988-11-07 | Yamaha Corp | Optical disk recorder |
EP0317344A2 (en) * | 1987-11-18 | 1989-05-24 | Sharp Kabushiki Kaisha | An optical memory medium |
JPH01150230A (en) * | 1987-12-07 | 1989-06-13 | Hitachi Ltd | Information recording method |
JPH0260917U (en) * | 1988-10-25 | 1990-05-07 | ||
JPH02246021A (en) * | 1989-03-17 | 1990-10-01 | Matsushita Electric Ind Co Ltd | Optical disk recording method |
JPH0378126A (en) * | 1989-08-22 | 1991-04-03 | Sony Corp | Optical write controller |
JPH05197958A (en) * | 1992-03-19 | 1993-08-06 | Hitachi Ltd | Method for recording optical information |
JPH06195711A (en) * | 1992-11-09 | 1994-07-15 | Internatl Business Mach Corp <Ibm> | System and method for pulse-width modulation of optical data storage |
JPH08235588A (en) * | 1996-03-11 | 1996-09-13 | Hitachi Ltd | Recording method of information |
JP2003085753A (en) * | 2001-09-10 | 2003-03-20 | Pioneer Electronic Corp | Method and device for recording information |
US7532557B2 (en) | 2004-03-31 | 2009-05-12 | Pioneer Corporation | Recording pulse generating apparatus and information recording apparatus |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS55139693A (en) * | 1979-04-17 | 1980-10-31 | Fujitsu Ltd | Write system for optical recording medium |
JPS5736439A (en) * | 1980-08-13 | 1982-02-27 | Matsushita Electric Ind Co Ltd | Information signal recorder |
JPS5817548A (en) * | 1981-07-22 | 1983-02-01 | Toshiba Corp | Optical information recording and reproduction system |
-
1985
- 1985-03-22 JP JP60055832A patent/JP2559362B2/en not_active Expired - Lifetime
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS55139693A (en) * | 1979-04-17 | 1980-10-31 | Fujitsu Ltd | Write system for optical recording medium |
JPS5736439A (en) * | 1980-08-13 | 1982-02-27 | Matsushita Electric Ind Co Ltd | Information signal recorder |
JPS5817548A (en) * | 1981-07-22 | 1983-02-01 | Toshiba Corp | Optical information recording and reproduction system |
Cited By (21)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS61237233A (en) * | 1985-04-15 | 1986-10-22 | Mitsubishi Electric Corp | Signal recording device |
JPH0658741B2 (en) * | 1985-04-15 | 1994-08-03 | 三菱電機株式会社 | Signal recording / reproducing device |
JPS63153726A (en) * | 1986-10-29 | 1988-06-27 | コーニンクレッカ フィリップス エレクトロニクス エヌ ヴィ | Method and apparatus for recording binary information signal |
JPS63160017A (en) * | 1986-12-23 | 1988-07-02 | Yamaha Corp | Optical disk recorder |
JPS63269321A (en) * | 1987-04-28 | 1988-11-07 | Yamaha Corp | Optical disk recorder |
EP0317344A2 (en) * | 1987-11-18 | 1989-05-24 | Sharp Kabushiki Kaisha | An optical memory medium |
US5754523A (en) * | 1987-11-18 | 1998-05-19 | Sharp Kabushiki Kaisha | Optical memory medium with preformed pit arrangement |
US5477524A (en) * | 1987-11-18 | 1995-12-19 | Sharp Kabushiki Kaisha | Optical memory medium with preformed pit arrangement |
JPH01150230A (en) * | 1987-12-07 | 1989-06-13 | Hitachi Ltd | Information recording method |
JPH0260917U (en) * | 1988-10-25 | 1990-05-07 | ||
JPH02246021A (en) * | 1989-03-17 | 1990-10-01 | Matsushita Electric Ind Co Ltd | Optical disk recording method |
JPH0378126A (en) * | 1989-08-22 | 1991-04-03 | Sony Corp | Optical write controller |
JPH05197958A (en) * | 1992-03-19 | 1993-08-06 | Hitachi Ltd | Method for recording optical information |
JPH06195711A (en) * | 1992-11-09 | 1994-07-15 | Internatl Business Mach Corp <Ibm> | System and method for pulse-width modulation of optical data storage |
JPH08235588A (en) * | 1996-03-11 | 1996-09-13 | Hitachi Ltd | Recording method of information |
JP2003085753A (en) * | 2001-09-10 | 2003-03-20 | Pioneer Electronic Corp | Method and device for recording information |
US7349316B2 (en) | 2001-09-10 | 2008-03-25 | Pioneer Corporation | Information recording apparatus and information recording method |
US7474601B2 (en) | 2001-09-10 | 2009-01-06 | Pioneer Corporation | Information recording apparatus and information recording method |
JP4560251B2 (en) * | 2001-09-10 | 2010-10-13 | パイオニア株式会社 | Information recording apparatus and information recording method |
US7532557B2 (en) | 2004-03-31 | 2009-05-12 | Pioneer Corporation | Recording pulse generating apparatus and information recording apparatus |
US7564759B2 (en) | 2004-03-31 | 2009-07-21 | Pioneer Corporation | Recording pulse generating apparatus and information recording apparatus |
Also Published As
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