CN101828225B - Optical pickup device, objective optical element for optical pickup device and optical information recorder/reproducer - Google Patents

Optical pickup device, objective optical element for optical pickup device and optical information recorder/reproducer Download PDF

Info

Publication number
CN101828225B
CN101828225B CN2008801118126A CN200880111812A CN101828225B CN 101828225 B CN101828225 B CN 101828225B CN 2008801118126 A CN2008801118126 A CN 2008801118126A CN 200880111812 A CN200880111812 A CN 200880111812A CN 101828225 B CN101828225 B CN 101828225B
Authority
CN
China
Prior art keywords
light beam
optical element
optical
base configuration
path difference
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.)
Expired - Fee Related
Application number
CN2008801118126A
Other languages
Chinese (zh)
Other versions
CN101828225A (en
Inventor
中村健太郎
木村彻
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Konica Minolta Opto Inc
Original Assignee
Konica Minolta Opto Inc
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
Application filed by Konica Minolta Opto Inc filed Critical Konica Minolta Opto Inc
Publication of CN101828225A publication Critical patent/CN101828225A/en
Application granted granted Critical
Publication of CN101828225B publication Critical patent/CN101828225B/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • 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
    • G11B7/1372—Lenses
    • G11B7/1374—Objective lenses
    • 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
    • G11B7/127—Lasers; Multiple laser arrays
    • G11B7/1275—Two or more lasers having different wavelengths
    • 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
    • G11B7/1353—Diffractive elements, e.g. holograms or gratings
    • 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
    • G11B2007/0003—Recording, reproducing or erasing systems characterised by the structure or type of the carrier
    • G11B2007/0006—Recording, reproducing or erasing systems characterised by the structure or type of the carrier adapted for scanning different types of carrier, e.g. CD & DVD

Landscapes

  • Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Optical Head (AREA)
  • Optical Recording Or Reproduction (AREA)
  • Lenses (AREA)

Abstract

An optical pickup device which can record and/or reproduce information appropriately on/from three kinds of discs having different recording densities while achieving simplification of configuration and cost reduction. An objective optical element and an optical information recorder/reproducer are also provided. During use of a BD, a first light beam enters an objective optical element (OBJ) under the state of infinite parallel light beam, but a second light beam during use of a DVD and a third light beam during use of a CD are made to enter the objective optical element (OBJ) under the state of finite divergence light beam. Consequently, the aberration correction amount required during compatible use of DVD and CD can be limited and the degree of contribution of the production error or transfer error of a die for molding the objective optical element (OBJ) can be limited by increasing the zone pitch (reducing the power of diffraction) of an optical path difference imparting structure. Furthermore, since the position where the third light beam is collected becomes distant from the objective optical element (OBJ), a long working distance can be assured or the zone pitch of the optical path difference imparting structure can be made small.

Description

Optical take-up apparatus, objective optical element for optical pickup device and optical information recording regenerator
Technical field
The present invention relates to exchange optical take-up apparatus, objective optical element for optical pickup device and the optical information recording regenerator of the information of carrying out record and/or regeneration to different types of CD.
Background technology
In recent years; In optical take-up apparatus; As for the information of reproduced light disc recording with to the light source of cd-rom recording of information; The short wavelengthization of the LASER Light Source that uses is made progress to some extent, for example, and bluish violet semiconductor laser and utilize the nonlinear optics effect to carry out the LASER Light Source practicability more and more of the blue SHG laser equiwavelength 400～420nm of infrared semiconductor laser wavelength conversion.Use the words of these bluish violet color laser light sources; When the object optical element that uses with the identical numerical aperture of DVD (digital universal disc) (NA); Can be to the information of video disc recording 15～20GB of diameter 12cm; The NA of object optical element is brought up at 0.85 o'clock, can write down the information of 23～25GB to the CD of diameter 12cm.In this instructions, the CD and the photomagneto disk that use the bluish violet color laser light source are generically and collectively referred to as " high density compact disc ".
Use in the high density compact disc of NA0.85 object lens owing to result from the CD side then the coma aberration that produces increases, so have protective seam is designed than DVD also thin (having only 0.1mm the 0.6mm of DVD relatively), to reduce the coma aberration amount of having quoted because of side.But, only can be definitely the high density compact disc of said kind be carried out the information recording/reproducing, be inadequate as the value of CD player/sound-track engraving apparatus (optical information recording regenerator) product.Consider the DVD that is writing down varied information, the present situation of CD (mini disk) sale are arranged now; It is not enough only can carrying out the information recording/reproducing to high density compact disc; Realizing that the DVD/CD that for example user is held can carry out the information recording/reproducing too definitely, is to lead to raising as the approach of high density compact disc with CD player/sound-track engraving apparatus value of the product.From above-mentioned background, hope to be equipped on high density compact disc with the optical take-up apparatus in CD player/sound-track engraving apparatus, have and not only keep any interchangeability of high density compact disc, DVD and CD but also the function of recording/reproducing information definitely.
As high density compact disc and DVD and CD any not only having been kept the interchangeability but also the method for recording/reproducing information definitely; The recording density that can consider respective record/regenerating information CD is optionally switched high density compact disc with optical system and DVD, the CD method with optical system; But need a plurality of optical system; Be unfavorable for miniaturization, cost rises in addition.
Therefore, in order to simplify the optical take-up apparatus structure, realize cost degradation, preferably in having the optical take-up apparatus of interchangeability, make high density compact disc general with optical system, to reduce the optics number as far as possible with optical system and DVD, CD.Make object optical element universalization facing to CD configuration, be help that optical take-up apparatus simplifies the structure most, cost degradation.In order to obtain the general object optical element of the mutually different multiple CD of recording/reproducing wavelength, the optical path difference that must on the object lens optical system, form the wavelength interdependence with spherical aberration is paid structure.
Put down in writing a kind of object lens optical system in the patent documentation 1 and carried the optical take-up apparatus of this object lens optical system, wherein, the object lens optical system has the diffraction structure of paying structure as optical path difference, can be common to high density compact disc and DVD in the past and CD.
Patent documentation 1: No. the 1304689th, European publication
Summary of the invention
The problem that the invention desire solves
Yet; That puts down in writing in the above-mentioned patent documentation 1 can exchange the object optical element that uses in the optical take-up apparatus of the information of carrying out record and/or regeneration to 3 kinds of different CDs, when the design specification of the optical take-up apparatus that has, might be used to the deficiency in light quantity that writes down and/or regenerate; Or carry out CD when following the tracks of; Light not produces harmful effect to following the tracks of with sensing, is difficult to correctly carry out the tracking of CD sometimes, existing problems.
Have trial on object optical element, to establish optical path difference and pay structure, the CD that passes it through adjustment uses up the first intrafascicular pinpointed focus and the light quantity of second pinpointed focus, the tracking characteristics when improving the CD use.But, to establish this optical path difference and pay structure, the endless belt tooth pitch is too short; The influence degree of the mould foozle of moulding object optical element and the transfer printing error of material rises; The utilization ratio of light reduces, and can not on information recording surface, obtain sufficient spot intensity, existing problems.
The present invention in view of the above problems; Purpose is to provide a kind of optical take-up apparatus, object optical element and optical information recording regenerator, wherein, and as object optical element; On simple lens, forming optical path difference pays when constructing; Also can improve the utilization ratio of light, can carry out information record and/or regeneration definitely, can oversimplify and cost degradation by implementation structure 3 kinds of different dishes of recording density such as high density compact disc, DVD, CD.
With the means that solve problem
In order to solve above-mentioned problem, the optical take-up apparatus of 1 record of claim the has:
First light source penetrates first light beam of first wavelength X 1;
Secondary light source penetrates second light beam of second wavelength X 2 (λ 2＞λ 1);
The 3rd light source penetrates the 3rd light beam of wavelength lambda 3 (λ 3＞λ 2);
Object optical element, be used for making said first beam condenser on the information recording surface of the 1st CD with thickness t 1 protective substrate, make said second beam condenser in have thickness t 2 (on the information recording surface of the 2nd CD of protective substrate of t1≤t2), make said the 3rd beam condenser in having thickness t 3 (on the information recording surface of the 3rd CD of protective substrate of t2＜t3); Optical take-up apparatus is characterised in that,
Said optical take-up apparatus through make said first beam condenser on the information recording surface of said the 1st CD, make said second beam condenser on the information recording surface of said the 2nd CD, make said the 3rd beam condenser on the information recording surface of said the 3rd CD; Thereby the information of carrying out record and/or regeneration
The optical surface of said object optical element has two zones of the neighboring area of middle section and said its central area at least, and said middle section has first optical path difference and pays structure, and said neighboring area has second optical path difference and pays structure,
Said object optical element will pass said first light beam of the said middle section of said object optical element can information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD, will pass said second light beam of said middle section can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 2nd CD, will pass said the 3rd light beam of said middle section can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 3rd CD
Said object optical element will pass said first light beam of the said neighboring area of said object optical element can information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD, will pass said second light beam of said neighboring area can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 2nd CD
Form first pinpointed focus and second pinpointed focus by passing said the 3rd light beam that said first optical path difference of said object optical element pays structure; The light quantity of the light quantity of said first pinpointed focus and said second pinpointed focus is greater than the light quantity of other any spots of said the 3rd light beam formation
Said first pinpointed focus and said second pinpointed focus satisfy following formula (1), while and following formula (2)～(5) of satisfying relevant multiplying power:
0.05≤L/f≤0.35 (1)
-0.01＜m1＜0.01 (2)
-0.05＜m2≤0.002 (3)
-0.05＜m3＜0.00 (4)
-0.02＜m2-m3≤0.02 (5)
Wherein,
F [mm]: when passing said the 3rd light beam that said first optical path difference pays structure and forming said first pinpointed focus, the focal length of said the 3rd light beam of said object optical element,
L [mm]: the distance between said first pinpointed focus and said second pinpointed focus.
M1: said object optical element is to the multiplying power of said first light beam
M2: said object optical element is to the multiplying power of said second light beam
M3: said object optical element is to the multiplying power of said the 3rd light beam.
According to the present invention; As long as satisfy (4) formula ground said the 3rd light beam is incided on the said object optical element with the state of limited divergent beams; Just can suppressing the different CD of protective substrate thickness, to exchange aberration correction necessary when using be less; So corresponding endless belt tooth pitch that optical path difference pays structure (promptly reduce diffraction and imitate power) that relaxes; It is less can suppressing the mould foozle of the said object optical element of moulding and the influence degree of transfer printing error like this, can guarantee the utilization ratio near design.And as long as satisfy (4) formula, then compare with the situation of m3=0, the spot position of said the 3rd light beam can be guaranteed long operating distance away from said object optical element.If or operating distance is identical, then correspondingly power does not need, and has to relax the effect that optical path difference is paid structure endless belt tooth pitch.
In addition; Through satisfying (5) formula, can make the multiplying power of said second light beam and said the 3rd light beam slightly identical, like this; Through for example using secondary light source and said the 3rd light source are housed in 2 wavelength lasers in the common plug-in unit etc.; Can realize the miniaturization of optical take-up apparatus, or suppress the displacement of the collimation lens of said second light beam and the common incident of said the 3rd light beam, further realize the miniaturization of optical take-up apparatus.
The optical take-up apparatus of 2 records of claim the is inventions of record in 1 of the claim the, it is characterized in that, satisfy following formula (1 '):
0.05≤L/f≤0.25(1‘)
The optical take-up apparatus of 3 records of claim the is inventions of record among 1 of claim the or the 2nd, it is characterized in that, is provided with the collimation lens that said second light beam and said the 3rd light beam pass jointly.
The optical take-up apparatus of 4 records of claim the is inventions of putting down in writing in any one of 1 of claim the～3rd, it is characterized in that said secondary light source and said the 3rd light source are by blocking.
The optical take-up apparatus of 5 records of claim the is inventions of putting down in writing in any one of 1 of claim the～4th, it is characterized in that,
Pass in the spot that said the 3rd light beam of said object optical element forms on the information recording surface of said the 3rd CD; When optical axis direction is seen; From the spot center laterally successively; Formed the high spot central part of light quantity density, spot pars intermedia, light quantity density that light quantity density is lower than said spot central part is higher than the spot periphery that said spot pars intermedia is lower than said spot central part
Said spot central part is used to the information record and/or the regeneration of said the 3rd CD, and said spot pars intermedia and said spot periphery are not used in the information record and/or the regeneration of said the 3rd CD,
Pay said the 3rd light beam of structure by said second optical path difference of passing said object optical element, on the information recording surface of said the 3rd CD, form said spot periphery.
The optical take-up apparatus of 6 records of claim the; It is the invention of putting down in writing in any one of 1 of claim the～5th; It is characterized in that; The said spot that the above the 3rd light beam of said first pinpointed focus forms is used for the record and/or the regeneration of said the 3rd CD, and the said spot that the above the 3rd light beam of said second pinpointed focus forms is not used in the record and/or the regeneration of said the 3rd CD.
The optical take-up apparatus of 7 records of claim the; It is the invention of putting down in writing in any one of 1 of claim the～6th; It is characterized in that the optical surface of said object optical element is around said neighboring area; Have and have the neighboring area that the 3rd optical path difference is paid structure, have three zones.
The optical take-up apparatus of 8 records of claim the; It is the invention of record in 7 of the claims the; It is characterized in that; Said object optical element will pass said first light beam of the said neighboring area of said object optical element, can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD.
The optical take-up apparatus of 9 records of claim the is inventions of putting down in writing in any one of 1 of claim the～8th, it is characterized in that the tooth pitch of the minimum of said object optical element is wider than 6 μ m.
The optical take-up apparatus of 10 records of claim the is inventions of putting down in writing in any one of 1 of claim the～9th, it is characterized in that said object optical element is a simple lens.
The optical take-up apparatus of 11 records of claim the is inventions of record in 10 of the claims the, it is characterized in that said object optical element is a plastic lens.
The objective optical element for optical pickup device of 12 records of claim the, this optical take-up apparatus has:
First light source penetrates first light beam of first wavelength X 1;
Secondary light source penetrates second light beam of second wavelength X 2 (λ 2＞λ 1);
The 3rd light source penetrates the 3rd light beam of wavelength lambda 3 (λ 3＞λ 2);
With said first light beam the 1st CD with thickness t 1 protective substrate is carried out information record and/or regeneration; (t1≤t2) the 2nd CD of protective substrate carries out information record and/or regeneration to having thickness t 2 with said second light beam; (t2＜t3) the 3rd CD of protective substrate carries out information record and/or regeneration to having thickness t 3 with said the 3rd light beam
Objective optical element for optical pickup device is characterised in that,
The optical surface of said object optical element has two zones of the neighboring area of middle section and said its central area at least, and said middle section has first optical path difference and pays structure, and said neighboring area has second optical path difference and pays structure,
Said object optical element will pass said first light beam of the said middle section of said object optical element can information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD, will pass said second light beam of said middle section can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 2nd CD, will pass said the 3rd light beam of said middle section can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 3rd CD
Said object optical element will pass said first light beam of the said neighboring area of said object optical element can information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD, will pass said second light beam of said neighboring area can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 2nd CD
Form first pinpointed focus and second pinpointed focus by passing said the 3rd light beam that said first optical path difference of said object optical element pays structure; The light quantity of the light quantity of said first pinpointed focus and said second pinpointed focus is greater than the light quantity of other any spots of said the 3rd light beam formation
Said first pinpointed focus and said second pinpointed focus satisfy following formula (1), while and following formula (2)～(5) of satisfying relevant multiplying power:
0.05≤L/f≤0.35 (1)
-0.01＜m1＜0.01 (2)
-0.05＜m2≤0.002 (3)
-0.05＜m3＜0.00 (4)
-0.02＜m2-m3≤0.02?(5)
Wherein,
F [mm]: when passing said the 3rd light beam that said first optical path difference pays structure and forming said first pinpointed focus, the focal length of said the 3rd light beam of said object optical element,
L [mm]: the distance between said first pinpointed focus and said second pinpointed focus.
M1: said object optical element is to the multiplying power of said first light beam
M2: said object optical element is to the multiplying power of said second light beam
M3: said object optical element is to the multiplying power of said the 3rd light beam.
The objective optical element for optical pickup device of 13 records of claim the is inventions of record in 12 of the claims the, it is characterized in that, satisfy following formula (1 '):
0.05≤L/f≤0.25(1‘)。
The objective optical element for optical pickup device of 14 records of claim the is inventions of record among 12 of claims the or the 13rd, it is characterized in that, is provided with the collimation lens that said second light beam and said the 3rd light beam pass jointly.
The objective optical element for optical pickup device of 15 records of claim the is inventions of putting down in writing in any one of 12 of claims the～14th, it is characterized in that said secondary light source and said the 3rd light source are by blocking.
The objective optical element for optical pickup device of 16 records of claim the is inventions of putting down in writing in any one of 12 of claims the～15th, it is characterized in that,
On the position that forms said first pinpointed focus; In the spot that forms by said the 3rd light beam that passes said object optical element; When optical axis direction is seen; From the spot center laterally successively, formed the high spot central part of light quantity density, spot pars intermedia, light quantity density that light quantity density is lower than said spot central part is higher than the spot periphery that said spot pars intermedia is lower than said spot central part
Said the 3rd light beam of being paid structure by said second optical path difference of passing said object optical element forms said spot periphery.
The objective optical element for optical pickup device of 17 records of claim the; It is the invention of putting down in writing in any one of 12 of claims the～16th; It is characterized in that; Said object optical element has and has the neighboring area that the 3rd optical path difference is paid structure around said neighboring area.
The objective optical element for optical pickup device of 18 records of claim the; It is the invention of record in 17 of the claims the; It is characterized in that; Said object optical element will pass said first light beam of the said neighboring area of said object optical element, can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD.
The objective optical element for optical pickup device of 19 records of claim the is inventions of putting down in writing in any one of 12 of claims the～18th, it is characterized in that the tooth pitch of the minimum of said object optical element is wider than 6 μ m.
The objective optical element for optical pickup device of 20 records of claim the is inventions of putting down in writing in any one of 12 of claims the～19th, it is characterized in that said object optical element is a simple lens.
The objective optical element for optical pickup device of 21 records of claim the is inventions of record in 20 of the claims the, it is characterized in that said object optical element is a plastic lens.
The optical information recording regenerator of 22 records of claim the has optical take-up apparatus, and this optical take-up apparatus has: first light source that penetrates first light beam of first wavelength X 1; Penetrate the secondary light source of second light beam of second wavelength X 2 (λ 2＞λ 1); Penetrate the 3rd light source of the 3rd light beam of wavelength lambda 3 (λ 3＞λ 2); Be used for making said first beam condenser on the 1st optical disc information record surface with thickness t 1 protective substrate, make said second beam condenser in have thickness t 2 (on the 2nd optical disc information record surface of the protective substrate of t1≤t2), make said the 3rd beam condenser in having the thickness t 3 (object optical element on the 3rd optical disc information record surface of the protective substrate of t2＜t3); Thereby said optical take-up apparatus through make said first beam condenser on the information recording surface of said the 1st CD, make said second beam condenser on the information recording surface of said the 2nd CD, make said the 3rd beam condenser on the information recording surface of said the 3rd CD, carry out information record and/or regeneration
Optical information recording regenerator is characterised in that,
The optical surface of said object optical element has two zones of the neighboring area of middle section and said its central area at least, and said middle section has first optical path difference and pays structure, and said neighboring area has second optical path difference and pays structure,
Said object optical element will pass said first light beam of the said middle section of said object optical element can information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD, will pass said second light beam of said middle section can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 2nd CD, will pass said the 3rd light beam of said middle section can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 3rd CD
Said object optical element will pass said first light beam of the said neighboring area of said object optical element can information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD, will pass said second light beam of said neighboring area can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 2nd CD
Form first pinpointed focus and second pinpointed focus by passing said the 3rd light beam that said first optical path difference of said object optical element pays structure; The light quantity of the light quantity of said first pinpointed focus and said second pinpointed focus is greater than the light quantity of other any spots of said the 3rd light beam formation; Said first pinpointed focus and said second pinpointed focus satisfy following formula (1), while and following formula (2)～(5) of satisfying relevant multiplying power:
0.05≤L/f≤0.35 (1)
-0.01＜m1＜0.01 (2)
-0.05＜m2≤0.002 (3)
-0.05＜m3＜0.00 (4)
-0.02＜m2-m3≤0.02 (5)
Wherein,
F [mm]: when passing said the 3rd light beam that said first optical path difference pays structure and forming said first pinpointed focus, the focal length of said the 3rd light beam of said object optical element,
L [mm]: the distance between said first pinpointed focus and said second pinpointed focus.
M1: said object optical element is to the multiplying power of said first light beam
M2: said object optical element is to the multiplying power of said second light beam
M3: said object optical element is to the multiplying power of said the 3rd light beam.
The optical information recording regenerator of 23 records of claim the; It is the invention of record in 22 of the claims the; It is characterized in that; Pass in the spot that said the 3rd light beam of said object optical element forms on the information recording surface of said the 3rd CD, when optical axis direction is seen, laterally successively from the spot center; Formed the high spot central part of light quantity density, spot pars intermedia, light quantity density that light quantity density is lower than said spot central part is higher than the spot periphery that said spot pars intermedia is lower than said spot central part
Said spot central part is used to the information record and/or the regeneration of said the 3rd CD, and said spot pars intermedia and said spot periphery are not used in the information record and/or the regeneration of said the 3rd CD,
By passing said the 3rd light beam that said second optical path difference of said object optical element is paid structure, on the information recording surface of said the 3rd CD, form said spot periphery.
The optical take-up apparatus of 24 records of claim the has: first light source that penetrates first light beam of first wavelength X 1; Penetrate the secondary light source of second light beam of second wavelength X 2 (λ 2＞λ 1); Penetrate the 3rd light source of the 3rd light beam of wavelength lambda 3 (λ 3＞λ 2); Be used for making said first beam condenser on the 1st optical disc information record surface with thickness t 1 protective substrate, make said second beam condenser in have thickness t 2 (on the 2nd optical disc information record surface of the protective substrate of t1≤t2), make said the 3rd beam condenser in having the thickness t 3 (object optical element on the 3rd optical disc information record surface of the protective substrate of t2＜t3); Thereby through make said first beam condenser on the information recording surface of said the 1st CD, make said second beam condenser on the information recording surface of said the 2nd CD, make said the 3rd beam condenser on the information recording surface of said the 3rd CD, carry out information record and/or regeneration
The optical surface of said object optical element has two zones of the neighboring area of middle section and said its central area at least, and said middle section has first optical path difference and pays structure, and said neighboring area has second optical path difference and pays structure,
Said object optical element will pass said first light beam of the said middle section of said object optical element can information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD, will pass said second light beam of said middle section can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 2nd CD, will pass said the 3rd light beam of said middle section can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 3rd CD
Said object optical element will pass said first light beam of the said neighboring area of said object optical element can information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD, will pass said second light beam of said neighboring area can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 2nd CD
It is overlapping first base configuration and second base configuration and the structure that constitutes at least that said first optical path difference is paid structure,
Said first base configuration is to make 2 diffraction light quantities of said first light beam that passes said first base configuration pay structure greater than 1 diffraction light quantity of the diffraction light quantity of other any number of times, said the 3rd light beam greater than the optical path difference of the diffraction light quantity of other any number of times greater than 1 diffraction light quantity of the diffraction light quantity of other any number of times, said second light beam
Said second base configuration be 0 diffraction light quantity making said first light beam that passes said second base configuration greater than 0 diffraction light quantity of the diffraction light quantity of other any number of times, said second light beam greater than the diffraction light quantity of other any number of times, said the 3rd light beam ± 1 time the diffraction light quantity is paid structure greater than the optical path difference of the diffraction light quantity of other any number of times, and satisfies following formula (2)～(5) of relevant multiplying power:
-0.01＜m1＜0.01 (2)
-0.05＜m2≤0.002 (3)
-0.05＜m3＜0.00 (4)
-0.02＜m2-m3≤0.02 (5)
Wherein,
M1: said object optical element is to the multiplying power of said first light beam
M2: said object optical element is to the multiplying power of said second light beam
M3: said object optical element is to the multiplying power of said the 3rd light beam.
The optical take-up apparatus of 25 records of claim the; It is the invention of record in 24 of the claims the; It is characterized in that; It is to have said first base configuration at least that said second optical path difference is paid structure; Any one structure of the 5th base configuration or the 6th base configuration; Said the 5th base configuration is to make the diffraction light quantity of 1 diffraction light quantity of said first light beam that passes said the 5th base configuration greater than other any number of times; 1 diffraction light quantity of said second light beam is greater than the diffraction light quantity of other any number of times; 1 diffraction light quantity of said the 3rd light beam is paid structure greater than the optical path difference of the diffraction light quantity of other any number of times
Said the 6th base configuration is to make 3 diffraction light quantities of said first light beam that passes said the 6th base configuration pay structure greater than 2 diffraction light quantities of the diffraction light quantity of other any number of times, said the 3rd light beam greater than the optical path difference of the diffraction light quantity of other any number of times greater than 2 diffraction light quantities of the diffraction light quantity of other any number of times, said second light beam.
The optical take-up apparatus of 26 records of claim the is inventions of record among 24 of claims the or the 25th, it is characterized in that the tooth pitch of the minimum of said object optical element is wider than 6 μ m.
The optical take-up apparatus of 27 records of claim the is inventions of putting down in writing in any one of 24 of claims the～26th, it is characterized in that said object optical element is a simple lens.
The optical take-up apparatus of 28 records of claim the is inventions of record in 27 of the claims the, it is characterized in that said object optical element is a plastic lens.
The optical take-up apparatus of 29 records of claim the; It is the invention of putting down in writing in any one of 24 of claims the～28th; It is characterized in that; It is except said first base configuration and said second base configuration and any one structure of overlapping the 3rd base configuration or the 7th base configuration that said first optical path difference is paid structure
Said the 3rd base configuration is to make 10 diffraction light quantities of said first light beam that passes said the 3rd base configuration pay structure greater than 5 diffraction light quantities of the diffraction light quantity of other any number of times, said the 3rd light beam greater than the optical path difference of the diffraction light quantity of other any number of times greater than 6 diffraction light quantities of the diffraction light quantity of other any number of times, said second light beam
Said the 7th base configuration is to make 2 diffraction light quantities of said first light beam that passes said the 7th base configuration pay structure greater than 1 diffraction light quantity of the diffraction light quantity of other any number of times, said the 3rd light beam greater than the optical path difference of the diffraction light quantity of other any number of times greater than 1 diffraction light quantity of the diffraction light quantity of other any number of times, said second light beam.
The optical take-up apparatus of 30 records of claim the; It is the invention of record in 29 of the claims the; It is characterized in that; It is except any one of said first base configuration, said the 5th base configuration or said the 6th base configuration that said second optical path difference is paid structure, and the overlapping any one structure of said the 3rd base configuration, the 4th base configuration or the 7th base configuration
Said the 4th base configuration is to make 5 diffraction light quantities of said first light beam that passes said the 4th base configuration pay structure greater than 2 diffraction light quantities of the diffraction light quantity of other any number of times, said the 3rd light beam greater than the optical path difference of the diffraction light quantity of other any number of times greater than 3 diffraction light quantities of the diffraction light quantity of other any number of times, said second light beam.
The optical take-up apparatus of 31 records of claim the is inventions of record in 30 of the claims the, it is characterized in that, the optical surface of said object optical element has around said neighboring area and has the neighboring area that the 3rd optical path difference is paid structure,
With said first light beam that passes the said neighboring area of said object optical element can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD,
It is any one structure that has said the 3rd base configuration, said the 4th base configuration or the 7th base configuration at least that said the 3rd optical path difference is paid structure.
The objective optical element for optical pickup device of 32 records of claim the, this optical take-up apparatus has: first light source, penetrate first light beam of first wavelength X 1; Secondary light source penetrates second light beam of second wavelength X 2 (λ 2＞λ 1); The 3rd light source penetrates the 3rd light beam of wavelength lambda 3 (λ 3＞λ 2); Optical take-up apparatus carries out information record and/or regeneration with said first light beam to the 1st CD with thickness t 1 protective substrate; (t1≤t2) the 2nd CD of protective substrate carries out information record and/or regeneration to having thickness t 2 with said second light beam; (t2＜t3) the 3rd CD of protective substrate carries out information record and/or regeneration to having thickness t 3 with said the 3rd light beam
Objective optical element for optical pickup device is characterised in that,
The optical surface of said object optical element has two zones of the neighboring area of middle section and said its central area at least, and said middle section has first optical path difference and pays structure, and said neighboring area has second optical path difference and pays structure,
Said object optical element will pass said first light beam of the said middle section of said object optical element can information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD, will pass said second light beam of said middle section can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 2nd CD, will pass said the 3rd light beam of said middle section can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 3rd CD
Said object optical element will pass said first light beam of the said neighboring area of said object optical element can information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD, will pass said second light beam of said neighboring area can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 2nd CD
It is overlapping first base configuration and second base configuration and the structure that constitutes at least that said first optical path difference is paid structure,
Said first base configuration is to make 2 diffraction light quantities of said first light beam that passes said first base configuration pay structure greater than 1 diffraction light quantity of the diffraction light quantity of other any number of times, said the 3rd light beam greater than the optical path difference of the diffraction light quantity of other any number of times greater than 1 diffraction light quantity of the diffraction light quantity of other any number of times, said second light beam
Said second base configuration be 0 diffraction light quantity making said first light beam that passes said second base configuration greater than 0 diffraction light quantity of the diffraction light quantity of other any number of times, said second light beam greater than the diffraction light quantity of other any number of times, said the 3rd light beam ± 1 time the diffraction light quantity is paid structure greater than the optical path difference of the diffraction light quantity of other any number of times, and satisfies following formula (2)～(5) of relevant multiplying power:
-0.01＜m1＜0.01 (2)
-0.05＜m2≤0.002 (3)
-0.05＜m3＜0.00 (4)
-0.02＜m2-m3≤0.02 (5)
Wherein,
M1: said object optical element is to the multiplying power of said first light beam
M2: said object optical element is to the multiplying power of said second light beam
M3: said object optical element is to the multiplying power of said the 3rd light beam.
The objective optical element for optical pickup device of 33 records of claim the; It is the invention of record in 32 of the claims the; It is characterized in that it is any one structure that has said first base configuration, the 5th base configuration or the 6th base configuration at least that said second optical path difference is paid structure
Said the 5th base configuration is to make 1 diffraction light quantity of said first light beam that passes said the 5th base configuration pay structure greater than 1 diffraction light quantity of the diffraction light quantity of other any number of times, said the 3rd light beam greater than the optical path difference of the diffraction light quantity of other any number of times greater than 1 diffraction light quantity of the diffraction light quantity of other any number of times, said second light beam
Said the 6th base configuration is to make 3 diffraction light quantities of said first light beam that passes said the 6th base configuration pay structure greater than 2 diffraction light quantities of the diffraction light quantity of other any number of times, said the 3rd light beam greater than the optical path difference of the diffraction light quantity of other any number of times greater than 2 diffraction light quantities of the diffraction light quantity of other any number of times, said second light beam.
The objective optical element for optical pickup device of 34 records of claim the is inventions of record among 32 of claims the or the 33rd, it is characterized in that the tooth pitch of the minimum of said object optical element is wider than 6 μ m.
The objective optical element for optical pickup device of 35 records of claim the is inventions of putting down in writing in any one of 32 of claims the～34th, it is characterized in that said object optical element is a simple lens.
The objective optical element for optical pickup device of 36 records of claim the is inventions of record in 35 of the claims the, it is characterized in that said object optical element is a plastic lens.
The objective optical element for optical pickup device of 37 records of claim the; It is the invention of putting down in writing in any one of 32 of claims the～36th; It is characterized in that; It is except said first base configuration and said second base configuration and any one structure of overlapping the 3rd base configuration or the 7th base configuration that said first optical path difference is paid structure
Said the 3rd base configuration is to make 10 diffraction light quantities of said first light beam that passes said the 3rd base configuration pay structure greater than 5 diffraction light quantities of the diffraction light quantity of other any number of times, said the 3rd light beam greater than the optical path difference of the diffraction light quantity of other any number of times greater than 6 diffraction light quantities of the diffraction light quantity of other any number of times, said second light beam
Said the 7th base configuration is to make 2 diffraction light quantities of said first light beam that passes said the 7th base configuration pay structure greater than 1 diffraction light quantity of the diffraction light quantity of other any number of times, said the 3rd light beam greater than the optical path difference of the diffraction light quantity of other any number of times greater than 1 diffraction light quantity of the diffraction light quantity of other any number of times, said second light beam.
The objective optical element for optical pickup device of 38 records of claim the; It is the invention of record in 37 of the claims the; It is characterized in that; It is except any one of said first base configuration, said the 5th base configuration or said the 6th base configuration that said second optical path difference is paid structure, and the overlapping any one structure of said the 3rd base configuration, the 4th base configuration or the 7th base configuration
Said the 4th base configuration is to make 5 diffraction light quantities of said first light beam that passes said the 4th base configuration pay structure greater than 2 diffraction light quantities of the diffraction light quantity of other any number of times, said the 3rd light beam greater than the optical path difference of the diffraction light quantity of other any number of times greater than 3 diffraction light quantities of the diffraction light quantity of other any number of times, said second light beam.
The objective optical element for optical pickup device of 39 records of claim the; It is the invention of record in 38 of the claims the; It is characterized in that the optical surface of said object optical element has and has the neighboring area that the 3rd optical path difference is paid structure around said neighboring area
With said first light beam that passes the said neighboring area of said object optical element can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD,
It is any one structure that has said the 3rd base configuration, said the 4th base configuration or the 7th base configuration at least that said the 3rd optical path difference is paid structure.
The optical information recording regenerator of 40 records of claim the has optical take-up apparatus, and this optical take-up apparatus has: first light source, penetrate first light beam of first wavelength X 1; Secondary light source penetrates second light beam of second wavelength X 2 (λ 2＞λ 1); The 3rd light source penetrates the 3rd light beam of wavelength lambda 3 (λ 3＞λ 2); Be used for making said first beam condenser on the 1st optical disc information record surface with thickness t 1 protective substrate, make said second beam condenser in have thickness t 2 (on the 2nd optical disc information record surface of the protective substrate of t1≤t2), make said the 3rd beam condenser in having the thickness t 3 (object optical element on the 3rd optical disc information record surface of the protective substrate of t2＜t3); Said optical take-up apparatus through make said first beam condenser on the information recording surface of said the 1st CD, make said second beam condenser on the information recording surface of said the 2nd CD, make said the 3rd beam condenser on the information recording surface of said the 3rd CD; Thereby the information of carrying out record and/or regeneration
Optical information recording regenerator is characterised in that,
The optical surface of said object optical element has two zones of the neighboring area of middle section and said its central area at least, and said middle section has first optical path difference and pays structure, and said neighboring area has second optical path difference and pays structure,
Said object optical element will pass said first light beam of the said middle section of said object optical element can information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD, will pass said second light beam of said middle section can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 2nd CD, will pass said the 3rd light beam of said middle section can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 3rd CD
Said object optical element will pass said first light beam of the said neighboring area of said object optical element can information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD, will pass said second light beam of said neighboring area can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 2nd CD
It is overlapping first base configuration and second base configuration and the structure that constitutes at least that said first optical path difference is paid structure,
Said first base configuration is to make 2 diffraction light quantities of said first light beam that passes said first base configuration pay structure greater than 1 diffraction light quantity of the diffraction light quantity of other any number of times, said the 3rd light beam greater than the optical path difference of the diffraction light quantity of other any number of times greater than 1 diffraction light quantity of the diffraction light quantity of other any number of times, said second light beam
Said second base configuration be 0 diffraction light quantity making said first light beam that passes said second base configuration greater than 0 diffraction light quantity of the diffraction light quantity of other any number of times, said second light beam greater than the diffraction light quantity of other any number of times, said the 3rd light beam ± 1 time the diffraction light quantity is paid structure greater than the optical path difference of the diffraction light quantity of other any number of times, and satisfies following formula (2)～(5) of relevant multiplying power:
-0.01＜m1＜0.01 (2)
-0.05＜m2≤0.002 (3)
-0.05＜m3＜0.00 (4)
-0.02＜m2-m3≤0.02 (5)
Wherein,
M1: said object optical element is to the multiplying power of said first light beam
M2: said object optical element is to the multiplying power of said second light beam
M3: said object optical element is to the multiplying power of said the 3rd light beam.
Optical take-up apparatus of the present invention has at least 3 light sources of first light source, secondary light source, the 3rd light source.And, optical take-up apparatus of the present invention have be used for making first beam condenser on the information recording surface of the 1st CD, make second beam condenser on the information recording surface of the 2nd CD, make the light-gathering optics system of the 3rd beam condenser on the information recording surface of the 3rd CD.In addition, optical take-up apparatus of the present invention has the photo detector of the folded light beam of accepting the 1st CD, the 2nd CD or the 3rd CD.
The 1st CD has the protective substrate and the information recording surface of thickness t 1.The 2nd CD has thickness t 2 (protective substrate and the information recording surface of t1≤t2).The 3rd CD has thickness t 3 (protective substrate and the information recording surface of t2＜t3).Preferred the 1st CD is that high density compact disc, the 2nd CD are that DVD, the 3rd CD are CD, but are not limited thereto.In addition, compare during with t1=t2, be difficult to during t1＜t2 3 kinds of different CDs are write down and/or regenerate by the single lens objective optical element, better tracking when keeping the regeneration of the 3rd video disc recording simultaneously, still, the present invention but is that it becomes possibility.The 1st CD, the 2nd CD or the 3rd CD also can be the multiplayer optical disks with multi-layered information recording face.
In this instructions,, can enumerate object optical element by NA0.85 and carry out the CD that information recording/reproducing, protective substrate thickness are 0.1mm left and right sides specification (for example B D, Blu-ray disc (Blu-ray Disc)) as the example of high density compact disc.As the example of other high density compact discs, can enumerate that object optical element by NA 0.65 to 0.67 carries out the information recording/reproducing, protective substrate thickness is the CD (for example HD DVD abbreviates HD again as) of 0.6mm left and right sides specification.In addition, in the high density compact disc, comprise that also CD that number～tens of nm degree thickness diaphragms (protective substrate also comprises diaphragm in this instructions) are arranged on the information recording surface and protective substrate thickness are 0 CD.In addition, in the high density compact disc, also comprise with bluish violet semiconductor laser and bluish violet SHG laser as the photomagneto disk of information recording/reproducing with light source.And in this instructions; DVD is that the thickness that the object optical element by NA 0.60～0.67 degree carries out information recording/reproducing, protective substrate is the general name of the DVD series CD of 0.6mm degree, comprises DVD-ROM, DVD-Video, DVD-Audio, DVD-RAM, DVD-R, DVD-RW, DVD+R, DVD+RW etc.In addition in this instructions; CD is that the thickness that the object optical element by NA 0.45～0.51 degree carries out information recording/reproducing, protective substrate is the general name of the CD series CD of 1.2mm degree, comprises CD-ROM, CD-Audio, CD-Video, CD-R, CD-RW etc.Recording density is that the recording density of high density compact disc is the highest, subsequently reduces in proper order by DVD, CD.
The thickness t 1 of relevant protective substrate, t2, t3, the formula that preferably meets the following conditions (6), (7), (8), but be not limited thereto:
0.0750mm≤t1≤0.125mm or 0.5mm≤t1≤0.7mm (6)
0.5mm≤t2≤0.7mm (7)
1.0mm≤t3≤1.3mm (8)。
In this instructions, preferred first light source, secondary light source, the 3rd light source are LASER Light Sources.As LASER Light Source, can preferably adopt semiconductor laser, silicon laser etc.Wavelength X 3 (λ 3＞λ 2) formula that meets the following conditions (9), (10) of the wavelength X 2 (λ 2＞λ 1) of the wavelength X 1 of first light beam that preferably penetrates from first light source, second light beam that penetrates from secondary light source, the 3rd light beam that penetrates from the 3rd light source:
1.5×λ1＜λ2＜1.7×λ1 (9)
1.9×λ1＜λ3＜2.1×λ1 (10)。
When adopting BD or HD, DVD and CD respectively as the 1st CD, the 2nd CD, the 3rd CD; First wavelength X 1 of first light source is preferably below the above 440nm of 350nm; More preferably below the above 415nm of 380nm, second wavelength X 2 of secondary light source is preferably below the above 680nm of 570nm, more preferably below the above 670nm of 630nm; The wavelength lambda 3 of the 3rd light source is preferably below the above 880nm of 750nm, more preferably below the above 820nm of 760nm.
In addition, preferably secondary light source and the 3rd light source are carried out blocking.And can also add that except secondary light source, the 3rd light source first light source carries out blocking.So-called blocking is meant that for example secondary light source and the 3rd light source are fixed and is accommodated in 1 plug-in unit.
As photo detector, preferably adopt optical detectors such as photodiode.The light that on the information recording surface of CD, reflects incides photo detector, can access the signal that reads of the information that is recorded on each CD with its output signal.And, detect the spot shape variation on the photo detector, the light quantity variation of change in location, focusing to detect with track detects, and detects according to this object optical element is moved so that focus, follow the tracks of.Photo detector can be made up of a plurality of optical detectors.Photo detector also can have main optical detector and secondary optical detector.For example also can be following photo detector: the optical detector of 2 pairs be established in the optical detector both sides of the key light of using at the record regenerating of receiving information, and is accepted to follow the tracks of the secondary light of adjustment usefulness by the optical detector of these 2 pairs.In addition, photo detector can also have a plurality of photo detectors, and is corresponding with each light source.
Light-gathering optics system has object optical element.Light-gathering optics system can have only object optical element, but light-gathering optics system also can also have coupled lens such as collimation lens except object optical element.Coupled lens is meant simple lens or the lens combination that is configured between object optical element and the light source, changes beam divergence angle.Collimation lens is a kind of of coupled lens, is the light that incides on the collimation lens is become the lens that directional light penetrates.And light-gathering optics system also can have optical elements such as diffraction optical element, will be divided into two side beams of usefulness such as main beam that the information record regenerating uses and tracking from the light beam that light source penetrates.In this instructions, object optical element be meant in optical take-up apparatus, be configured in facing on the CD position, have a optical system with the function of the beam condenser that penetrates from light source on the optical disc information record surface.Preferred object optical element be in optical take-up apparatus, be configured in facing to CD locational, have a optical system with the function of the beam condenser that penetrates from light source on the optical disc information record surface, and through gearing at least can integraty displacement on optical axis direction optical system.Object optical element can be made up of a plurality of lens and the optical element more than two, also can only be single object optical element, but preferably single object optical element.In addition; Object optical element can be that glass lens also can be a plastic lens; Or also can be on glass lens, to establish the hybrid lens that optical path difference is paid structure etc. with light-cured resin etc., when object optical element has a plurality of lens, can mix and use glass lens and plastic lens.When object optical element has a plurality of lens, can be to have the combination that optical path difference is paid the planar optics element and the non-spherical lens (can have not to have optical path difference to pay structure yet) of structure.In addition, the plane of refraction of preferred object optical element is an aspheric surface.Also preferred object optical element is provided with optical path difference, and to pay the basal plane of structure be aspheric surface.
When making object optical element be glass lens, preferably use glass branchpoint Tg at the glass material below 400 ℃.Through using glass branchpoint Tg, can die life can be prolonged like this in the lower temperature moulding comparatively speaking at the glass material below 400 ℃.As the low glass material of this glass branchpoint Tg, for example there be (strain) to live K-PG325, K-PG375 (being all name of product) that field optical glass is made.
But glass lens in general proportion is bigger than resin lens, so making object optical element is the words weight increase of glass lens, increases the burden to the gearing that drives object optical element.For this reason, when making object optical element be glass lens, preferably use the little glass material of proportion.Concrete preferred specific gravity is below 3.0, more preferably below 2.8.
When making object optical element be plastic lens; The preferred cyclic olefin resinous materials of using, more preferably use in the cyclic olefin when 25 ℃ of temperature refractive index to wavelength 405nm be in 1.54 to 1.60 scopes, in-5 ℃ to 70 ℃ temperature ranges, follow temperature variation to the variations in refractive index rate dN/dT of wavelength 405nm (℃ -1) be-20 * 10 -5To-5 * 10 -5(more preferably be-10 * 10 -5To-8 * 10 -5) the interior resin material of scope.In addition, when making object optical element be plastic lens, preferably make coupled lens also be plastic lens.
Put down in writing in the face of object optical element down.At least one optical surface of object optical element has the neighboring area of middle section and its central area.More preferably at least one optical surface of object optical element has neighboring area around the neighboring area.Can be the CD of higher NA be write down and/or regenerates through establishing neighboring area.Preferred middle section is the zone that contains the object optical element optical axis, but also can be the zone that does not contain.Preferred middle section, neighboring area and neighboring area are located on the same optical surface.Preferably as shown in Figure 1, middle section CN, neighboring area MD, neighboring area OT are arranged on the same optical surface, and being with the optical axis is the concentric circles at center.In addition, the middle section of preferred object optical element is provided with first optical path difference and pays structure, and the neighboring area is provided with second optical path difference and pays structure.When neighboring area was arranged, neighboring area can be a plane of refraction, also can on neighboring area, establish the 3rd optical path difference and pay structure.Preferred middle section, neighboring area, neighboring area be adjacency respectively, but also can between gapped slightly.
Preferably on the zone more than 70% of object optical element middle section area, establish first optical path difference and pay structure, more preferably more than 90%.More preferably on whole of middle section, establish first optical path difference and pay structure.Preferably on the zone more than 70% of object optical element neighboring area area, establish second optical path difference and pay structure, more preferably more than 90%.More preferably on whole of neighboring area, establish first optical path difference and pay structure.Preferably on the zone more than 70% of the neighboring area of object optical element area, establish the 3rd optical path difference and pay structure, more preferably more than 90%.More preferably on whole of neighboring area, establish the 3rd optical path difference and pay structure.
So-called optical path difference in this instructions is paid structure, is the general name to the structure of incident beam additional optical path difference.Optical path difference is paid and is comprised also in the structure that the phase differential of paying phase differential pays structure.In addition, phase differential is paid and is comprised diffraction structure in the structure.Optical path difference is paid structure and is had step, preferably has a plurality of steps.By this step to incident beam additional optical path difference and/or phase differential.It can be the integral multiple of incident beam wavelength that optical path difference is paid the additional optical path difference of structure, also can be the non-integral multiple of incident beam wavelength.Step can be to hold the configuration of periodic intervals ground in the optical axis vertical direction, also can be to hold the configuration of aperiodicity compartment of terrain in the optical axis vertical direction.
The preferred light path difference is paid a plurality of endless belt that structure has with the optical axis concentric circles that is the center.Optical path difference is paid structure and can be got various cross sectional shapes (cross sectional shape that contains the face of optical axis) in addition.Pay the cross sectional shape of structure as the most general optical path difference, paying the cross sectional shape that structure contains optical axis just like the optical path difference shown in Fig. 2 (a) is jagged situation.On planar optical elements, establish optical path difference and pay when structure cross section and look it is stair-stepping, establish on non-spherical lens face etc. that also can be regarded as when same optical path difference is paid structure be the jagged cross sectional shape shown in Fig. 2 (a).Therefore, in the so-called jagged cross sectional shape, also comprise stair-stepping cross sectional shape in this instructions.In addition, pay structure through overlapping step towards different jagged optical path differences, the optical path difference that can also obtain the scale-of-two structure shown in Fig. 2 (b) is paid structure.First optical path difference in this instructions is paid structure and second optical path difference is paid structure; It can be the structure that the different zigzag optical path difference of its cross sectional shape is paid tectonic stacking; Also can be to pay scale-of-two structure optical path difference that tectonic stacking forms in the zigzag optical path difference to pay texturally, overlapping again zigzag optical path difference be paid the structure of structure.For example, Fig. 2 (c) is the structure of zigzag shape and scale-of-two tectonic stacking, and Fig. 2 (d) is serrulate structure and the overlapping structure of rough sawn toothed structure.
The optical path difference is here paid tectonic stacking, be optical surface decide on the zone, establish addendum modification and be a plurality of optical path differences and pay the optical path difference that the optical axis direction addendum modification of structure adds together and pay structure.
Be located at first optical path difference on the object optical element middle section second optical path difference on paying structure and being located at the object optical element neighboring area and pay structure and can be located on the different optical surface of object optical element, but preferably be located on the same optical surface.Through being located on the same optical surface, the eccentric error event that can reduce when making is preferred.In addition, compare with the situation on the face that is located at object optical element CD side, preferably on the face of object optical element light source side, establish first optical path difference pay the structure and second optical path difference pay structure.
Object optical element is provided with first optical path difference and pays first light beam of the middle section of structure, second light beam and the 3rd light beam passing object optical element, forms optically focused spot ground optically focused respectively.Preferred object optical element to pass object optical element be provided with first optical path difference pay first light beam of the middle section of structure can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of the 1st CD.In addition, object optical element to pass object optical element be provided with first optical path difference pay second light beam of the middle section of structure can information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of the 2nd CD.And, object optical element to pass object optical element be provided with first optical path difference pay the 3rd light beam of the middle section of structure can information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of the 3rd CD.In addition; The protective substrate thickness t 1 of the 1st CD and the protective substrate thickness t 2 of the 2nd CD are not simultaneously; Preferred first optical path difference is paid first light beam and second light beam that structure is paid structure to passing first optical path difference, revises owing to the protective substrate thickness t 2 of the protective substrate thickness t 1 of the 1st CD and the 2nd CD different cause the spherical aberration of generation and/or owing to the different spherical aberrations that cause generation with the wavelength of second light beam of first light beam.And; First optical path difference is paid first light beam and the 3rd light beam that structure is paid structure to passing first optical path difference, revises owing to the protective substrate thickness t 3 of the protective substrate thickness t 1 of the 1st CD and the 3rd CD different cause the spherical aberration of generation and/or owing to the different spherical aberrations that cause generation with the wavelength of the 3rd light beam of first light beam.
By passing the 3rd light beam that first optical path difference on the object optical element is paid structure, form in the spot that light quantity is maximum among the spot that the 3rd light beam forms first pinpointed focus and, the 3rd light beam form light quantity inferior to the second many pinpointed focus of first pinpointed focus.Preferably on first pinpointed focus by passing the 3rd light beam that object optical element first optical path difference is paid structure, the spot of the spot that the 3rd light beam forms footpath is minimum; The spot footpath of the spot that the 3rd light beam forms on second pinpointed focus is little inferior to first pinpointed focus.Be beam waist that minimum point is as pinpointed focus in certain de-focus region preferably.That is to say that preferred the 3rd light beam is that minimum point exists 2 points at least in certain de-focus region beam waist.In addition, the difference of diffraction efficiency and the diffraction efficiency of the diffraction light that forms second pinpointed focus of diffraction light that forms first pinpointed focus is 20% when following, and effect of the present invention is especially remarkable.
The spot that preferably the 3rd light beam forms on first pinpointed focus is used for the record and/or the regeneration of the 3rd CD; The spot that the 3rd light beam forms on second pinpointed focus is not used in the record and/or the regeneration of the 3rd CD, but also can be employed in record and/or the regeneration that the 3rd light beam forms on first pinpointed focus spot is not used in the 3rd CD, the spot that the 3rd light beam forms on second pinpointed focus is used for the record of the 3rd CD and/or the mode of regeneration.In addition, when first optical path difference is paid structure and is located on the face of object lens light source side, preferred second pinpointed focus than first pinpointed focus near object optical element.
First pinpointed focus and second pinpointed focus satisfy following formula (1).
0.05≤L/f≤0.35 (1)，
Wherein, f [mm] is meant that passing first optical path difference pays the focal length that structure forms the 3rd light beam of first pinpointed focus, and L [mm] is the distance between first pinpointed focus and second pinpointed focus.
More preferentially satisfy following formula (1 '):
0.05≤L/f≤0.25?(1‘)。
Through satisfying this formula; Can more relax the endless belt tooth pitch; The influence degree of transfer printing error of foozle and material of the mould of moulding object optical element can be reduced,, higher spot intensity can be on information recording surface, obtained so can improve the utilization ratio of light.
Preferred L is below the above 0.63mm of 0.18mm.F is below the above 3.0mm of 1.8mm.
Through satisfying formula (1), formula (1 '); When the 3rd video disc recording and/or regeneration; Can prevent in the 3rd light beam that no not light produces harmful effect to following the tracks of with photo detector when the 3rd video disc recording and/or regeneration, good performance for tracking in the time of can keeping the 3rd video disc recording and/or regeneration.
Object optical element is provided with first light beam and second light beam that second optical path difference is paid the neighboring area of structure to passing object optical element, forms optically focused spot ground optically focused respectively.Preferred object optical element to pass object optical element be provided with second optical path difference pay first light beam of the neighboring area of structure can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of the 1st CD.In addition, object optical element to pass object optical element be provided with second optical path difference pay second light beam of the neighboring area of structure can information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of the 2nd CD.In addition; The protective substrate thickness t 1 of the 1st CD and the protective substrate thickness t 2 of the 2nd CD are not simultaneously; Preferred second optical path difference is paid first light beam and second light beam that structure is paid structure to passing second optical path difference, revises owing to the protective substrate thickness t 2 of the protective substrate thickness t 1 of the 1st CD and the 2nd CD different cause the spherical aberration of generation and/or owing to the different spherical aberrations that cause generation with the wavelength of second light beam of first light beam.
As preferred mode, can enumerate the 3rd light beam that passes the neighboring area and be not used in the record of the 3rd CD and/or the mode of regeneration.The 3rd light beam that passes the neighboring area is not contributed the formation of the optically focused spot on the information recording surface of the 3rd CD.That is to say, preferably pass object optical element and be provided with the 3rd light beam that second optical path difference is paid the neighboring area of structure, on the information recording surface of the 3rd CD, form solar flare.As shown in Figure 6; Pass in the spot that the 3rd light beam of object optical element forms on the information recording surface of the 3rd CD; From optical axis side (or spot central part) laterally successively, has the high spot central part SCN of light quantity density, spot pars intermedia SMD that light quantity density is lower than spot central part, light quantity density than the low spot periphery SOT of spot pars intermedia height ratio spot central part.The spot central part is used for the information record and/or the regeneration of CD, and spot pars intermedia and spot periphery are not used in the information record and/or the regeneration of CD.Above-mentioned spot periphery is called solar flare.That is to say, pass object optical element and be provided with the 3rd light beam that second optical path difference is paid the neighboring area of structure, on the information recording surface of the 3rd CD, form the spot periphery.The optically focused spot or the spot of said here the 3rd light beam, the preferably spot on first pinpointed focus.In addition, preferably pass the spot that second light beam of object optical element forms on the information recording surface of the 2nd CD and also have spot central part, spot pars intermedia, spot periphery.
In addition, preferred second optical path difference is paid structure causes generation to first light beam that passes second optical path difference and pay structure and the second light beam correction owing to the wavelength small variations of first light source or secondary light source chromosphere surface aberration.The small variations of wavelength is meant ± the following change of 10nm.For example; The first light beam wavelength λ, 1 generation ± 5nm changes; Preferably pay the change that structure compensates the spherical aberration of first light beam that passes the neighboring area, make at the corrugated aberration variable quantity on the 1st optical disc information record surface below 0.095 λ 1rms more than the 0.010 λ 1rms by second optical path difference.In addition; The second light beam wavelength λ, 2 generation ± 5nm change; Preferably pay the change that structure compensates the spherical aberration of second light beam that passes the neighboring area, make at the corrugated aberration variable quantity on the 2nd optical disc information record surface below 0.03 λ 2rms more than the 0.002 λ 2rms by second optical path difference.Thus, can revise the foozle of light source optical maser wavelength and the irregular caused aberration of wavelength that individual difference brings.
When object optical element has neighboring area, object optical element will pass first light beam of the neighboring area of object optical element can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of the 1st CD.First light beam that preferably passes neighboring area its spherical aberration when the record of the 1st CD and/or regeneration obtains revising.
In addition as preferred mode, can enumerate record and/or regeneration that second light beam that passes neighboring area is not used in the 2nd CD, the 3rd light beam that passes neighboring area is not used in the record of the 3rd CD and/or the mode of regeneration.Preferably make second light beam and the 3rd light beam that pass neighboring area, respectively to the not contribution of formation of the optically focused spot on the information recording surface of the 2nd CD and the 3rd CD.That is to say, when object optical element has neighboring area, preferably pass the 3rd light beam of the neighboring area of object optical element, on the information recording surface of the 3rd CD, form solar flare.In other words, preferably pass the 3rd light beam of the neighboring area of object optical element, on the information recording surface of the 3rd CD, form the spot periphery.In addition, when object optical element has neighboring area, preferably pass second light beam of the neighboring area of object optical element, on the information recording surface of the 2nd CD, form solar flare.In other words, preferably pass second light beam of the neighboring area of object optical element, on the information recording surface of the 2nd CD, form the spot periphery.
Neighboring area has the 3rd optical path difference when paying structure, and the 3rd optical path difference is paid structure also can pay the first light beam correction of structure causes generation owing to the wavelength small variations of first light source chromosphere surface aberration to passing the 3rd optical path difference.The small variations of wavelength is meant ± the following change of 10nm.For example; The first light beam wavelength λ, 1 generation ± 5nm changes; Preferably pay the change of the spherical aberration of first light beam that structure compensation passes neighboring area, make at the corrugated aberration variable quantity on the 1st optical disc information record surface below 0.095 λ 1rms more than the 0.010 λ 1rms by the 3rd optical path difference.
It also can be the structure that zigzag diffraction structure and scale-of-two tectonic stacking form that first optical path difference is paid structure.In addition, to pay structure also can be zigzag diffraction structure and the overlapping structure that forms of thicker (tooth pitch is big) zigzag diffraction structure to second optical path difference.First optical path difference pays structure or second optical path difference is paid structure when being this superimposed structure; Relevant this zigzag diffraction structure (second optical path difference is paid (tooth pitch is big) diffraction structure thick when constructing); Can pay the suitable path difference of first wavelength X, 1 even-multiple of first light beam, the first beam wave surface phase place is not changed.And, when the wavelength lambda 3 of the 3rd light beam is the almost even-multiple wavelength of first wavelength of first light beam, be the optical path difference of paying integral multiple, same corrugated phase place does not change.Through this formation, the advantage that does not influence first light beam and the 3rd beam condenser owing to this diffraction structure is arranged.The following scope of (2n+0.1) * λ 1 on (2n-0.1) * λ 1 when so-called even-multiple quite is meant and is nature with n.
The structure of first optical path difference is paid structure first base configuration that can be overlapping at least and second base configuration.
First base configuration is to make 2 diffraction light quantities of first light beam that passes first base configuration pay structure greater than the diffraction light quantity of other any number of times, 1 diffraction light quantity of the 3rd light beam greater than the optical path difference of the diffraction light quantity of other any number of times greater than the diffraction light quantity of other any number of times, 1 diffraction light quantity of second light beam.Preferred first base configuration be with the slightly neat state in corrugated penetrate first light beam that passes first base configuration and the 3rd light beam, the optical path difference that penetrates second light beam that passes first base configuration with the irregular state in corrugated pays structure.In addition, preferred first base configuration is that the optical path difference that makes the angle of diffraction of second light beam that passes first base configuration be different from the angle of diffraction of first light beam and the 3rd light beam is paid structure.In addition; The step of preferred first base configuration optical axis direction height, be to the 1st light beam provide the 1st wavelength slightly 2 wavelength branch optical path differences, to the 2nd light beam provide the 2nd wavelength slightly 1.2 wavelength branch optical path differences, the 3rd light beam is provided the slightly step height of 1 wavelength branch optical path difference of the 3rd wavelength.
In addition, second base configuration be make 0 (seeing through light) diffraction light quantity of first light beam that passes second base configuration greater than 0 (seeing through light) diffraction light quantity of the diffraction light quantity of other any number of times, second light beam greater than the diffraction light quantity of other any number of times, the 3rd light beam ± 1 time the diffraction light quantity is paid structure greater than the optical path difference of the diffraction light quantity of other any number of times.Preferred second base configuration be with the slightly neat state in corrugated penetrate first light beam that passes second base configuration and second light beam, the optical path difference that penetrates the 3rd light beam that passes first base configuration with the irregular state in corrugated pays structure.In addition, preferred second base configuration is that the optical path difference that makes the angle of diffraction of the 3rd light beam that passes second base configuration be different from the angle of diffraction of first light beam and second light beam is paid structure.In addition; The step of preferred second base configuration optical axis direction height, be to the 1st light beam provide the 1st wavelength slightly 5 wavelength branch optical path differences, to the 2nd light beam provide the 2nd wavelength slightly 3 wavelength branch optical path differences, the 3rd light beam is provided the slightly step height of 2.5 wavelength branch optical path differences of the 3rd wavelength.And the shape of preferred second base configuration is the shape of the scale-of-two shape shown in Fig. 2 (b).
In addition, preferred second optical path difference pay the structure be any one structure that has said first base configuration, the 5th base configuration or the 6th base configuration at least.And it is not overlapping formation more than 2 among first base configuration, the 5th base configuration and the 6th base configuration that preferred second optical path difference is paid structure.When second optical path difference is paid structure and had first base configuration at least, pay identical base configuration of structure and design easily because have, so preferred with first optical path difference.
The 5th base configuration is to make 1 diffraction light quantity of first light beam that passes the 5th base configuration pay structure greater than the diffraction light quantity of other any number of times, 1 diffraction light quantity of the 3rd light beam greater than the optical path difference of the diffraction light quantity of other any number of times greater than the diffraction light quantity of other any number of times, 1 diffraction light quantity of second light beam.The step of preferred the 5th base configuration optical axis direction height, be to the 1st light beam provide the 1st wavelength summary 1 wavelength branch optical path difference, the 2nd light beam is provided the summary 0.6 wavelength branch optical path difference of the 2nd wavelength, the 3rd light beam is provided the step height of the summary 0.5 wavelength branch optical path difference of the 3rd wavelength.
The 6th base configuration is to make 3 diffraction light quantities of first light beam that passes the 6th base configuration pay structure greater than the diffraction light quantity of other any number of times, 2 diffraction light quantities of the 3rd light beam greater than the optical path difference of the diffraction light quantity of other any number of times greater than the diffraction light quantity of other any number of times, 2 diffraction light quantities of second light beam.The step of preferred the 6th base configuration optical axis direction height, be to the 1st light beam provide the 1st wavelength summary 3 wavelength branch optical path differences, the 2nd light beam is provided the summary 1.9 wavelength branch optical path differences of the 2nd wavelength, the 3rd light beam is provided the step height of the summary 1.6 wavelength branch optical path differences of the 3rd wavelength.
When object optical element was plastic lens, it was the triple superimposed structures that overlap three kinds of base configurations that preferred first optical path difference is paid structure.Concrete then preferably except first base configuration and second base configuration again the 3rd overlap base configuration or the 7th base configuration triple superimposed structures.Be more preferably except first base configuration and second base configuration and overlap the 3rd base configuration again.
The 3rd base configuration is to make 10 diffraction light quantities of first light beam that passes the 3rd base configuration pay structure greater than the diffraction light quantity of other any number of times, 5 diffraction light quantities of the 3rd light beam greater than the optical path difference of the diffraction light quantity of other any number of times greater than the diffraction light quantity of other any number of times, 6 diffraction light quantities of second light beam.The step of preferred the 3rd base configuration optical axis direction height, be to the 1st light beam provide the 1st wavelength summary 10 wavelength branch optical path differences, the 2nd light beam is provided the summary 6 wavelength branch optical path differences of the 2nd wavelength, the 3rd light beam is provided the step height of the summary 5 wavelength branch optical path differences of the 3rd wavelength.The 7th base configuration is to make 2 diffraction light quantities of first light beam that passes the 7th base configuration pay structure greater than the diffraction light quantity of other any number of times, 1 diffraction light quantity of the 3rd light beam greater than the optical path difference of the diffraction light quantity of other any number of times greater than the diffraction light quantity of other any number of times, 1 diffraction light quantity of second light beam.The step of preferred the 7th base configuration optical axis direction height, be to the 1st light beam provide the 1st wavelength summary 2 wavelength branch optical path differences, the 2nd light beam is provided the summary 1.2 wavelength branch optical path differences of the 2nd wavelength, the 3rd light beam is provided the step height of the summary 1 wavelength branch optical path difference of the 3rd wavelength.In addition; The 3rd base configuration and the 7th base configuration rise and during the wavelength elongation of first light source, secondary light source and the 3rd light source in temperature; Having the spherical aberration of making is not enough function; To reduce the spherical aberration that causes excessive for the refractive index of plastics when thus can compensation temperature rising, and can access good spherical aberration.And, to compare with the 3rd base configuration, the step degree of depth of the 7th base configuration can be more shallow.In addition, preferred the 3rd base configuration and the 7th base configuration are arranged on female aspheric surface (basal plane) different with first base configuration, second base configuration, the 5th base configuration and the 6th base configuration.Preferred the 3rd base configuration and the 7th base configuration when incident beam is provided above-mentioned optical path difference, be arranged on make the 3rd base configuration and the 7th base configuration do not influence as far as possible incident beam towards and on female aspheric surface (basal plane) of setting.And preferred the 3rd base configuration and the 7th base configuration are configurations: along with leaving optical axis and go deep into the optical element inboard, be boundary with the somewhere in the optical axis vertical direction, afterwards along with leaving optical axis to the optical element outside.(that is to say, preferably deepen gradually, be the structure that boundary shoals with the somewhere.)
When object optical element is plastic lens; It is except any one of first base configuration, the 5th base configuration or the 6th base configuration that preferred second optical path difference is paid structure, any one structure of overlapping again the 3rd base configuration, the 4th base configuration or the 7th base configuration.Preferably overlap the structure of first base configuration and the 4th base configuration.
The 4th base configuration is to make 5 diffraction light quantities of first light beam that passes the 4th base configuration pay structure greater than the diffraction light quantity of other any number of times, the 3rd light beam 3 times and 2 diffraction light quantities greater than the optical path difference of the diffraction light quantity of other any number of times greater than 3 diffraction light quantities of the diffraction light quantity of other any number of times, second light beam.And the some diffraction light quantities of diffraction light quantity of 3 diffraction lights of preferred the 3rd light beam greater than 2 diffraction lights.The step of preferred the 4th base configuration optical axis direction height, be to the 1st light beam provide the 1st wavelength summary 5 wavelength branch optical path differences, the 2nd light beam is provided the summary 3 wavelength branch optical path differences of the 2nd wavelength, the 3rd light beam is provided the step height of the summary 2.5 wavelength branch optical path differences of the 3rd wavelength.In addition; The 3rd base configuration and the 4th base configuration and the 7th base configuration rise and during the wavelength elongation of first light source, secondary light source and the 3rd light source in temperature; Having the spherical aberration of making is not enough function; To reduce the spherical aberration that causes excessive for the refractive index of plastics when thus can compensation temperature rising, and can access good spherical aberration.And the step degree of depth of comparing the 4th base configuration and the 7th base configuration with the 3rd base configuration can be more shallow.In addition, preferred the 3rd base configuration, the 4th base configuration and the 7th base configuration are arranged on female aspheric surface (basal plane) different with first base configuration, second base configuration, the 5th base configuration and the 6th base configuration.Preferred the 3rd base configuration, the 4th base configuration and the 7th base configuration when incident beam is provided above-mentioned optical path difference, be arranged on make the 3rd base configuration, the 4th base configuration and the 7th base configuration do not influence as far as possible incident beam towards and on female aspheric surface (basal plane) of setting.And preferred the 3rd base configuration, the 4th base configuration and the 7th base configuration are configurations: along with leaving optical axis and go deep into the optical element inboard, be boundary with the somewhere in the optical axis vertical direction, afterwards along with leaving optical axis to the optical element outside.(that is to say, preferably deepen gradually, be the structure that boundary shoals with the somewhere.)
And when object optical element is plastic lens, preferably has and have the neighboring area that the 3rd optical path difference is paid structure.At this moment, preferred the 3rd optical path difference pay the structure be any one structure that has the 3rd base configuration, the 4th base configuration or the 7th base configuration at least.The structure that preferably has the 4th base configuration.
When object optical element was the lens of glass lens and the formation of adiabatic resin, it was the structure that only overlaps first base configuration and second base configuration that preferred first optical path difference is paid structure.
In addition; Object optical element be glass lens and adiabatic resin form lens the time, preferred second optical path difference is paid any one structure that structure is overlapping again the 3rd base configuration or the 4th base configuration except any one of first base configuration, the 5th base configuration or the 6th base configuration.Preferably overlap the structure of first base configuration and the 4th base configuration.
And, object optical element be glass lens and adiabatic resin form lens the time, preferably have neighboring area for plane of refraction.
When object optical element was plastic lens, it was the zonal structure with concentric circles of step that preferred first optical path difference is paid structure, and first optical path difference is paid the step height of structure, had at least 2 kinds step height among following dA, dB, dC, the dD:
0.9{15 λ B/ (n-1) one 2 λ B '/(n '-1) }＜dA (μ m)＜1.5{15 λ B/ (n-1)-2 λ B '/(n '-1) } (17),
0.9·{5λB/(n-1)+2λB’/(n’-1)}＜dB(μm)＜1.5·{5λB/(n-1)+2λB’/(n’-1)}(18)，
0.9·5λB/(n-1)＜d?C(μm)＜1.5·5λB/(n-1) (19)，
0.9·{5λB/(n-1)-2λB’/(n’-1)}＜dD(μm)＜1.5·{5λB/(n-1)-2λB’/(n’-1)}(20)。
And preferred above-mentioned formula (17) is following formula (17) ': 0.95{15 λ B/ (n-1)-2 λ B '/(n '-1) }＜dA (μ m)＜1.4{15 λ B/ (n-1)-2 λ B '/(n '-1) } (17) ',
More preferably above-mentioned formula (17) is following formula (17) ":
1.0·{15λB/(n-1)-2λB’/(n’-1)}≤dA(μm)＜1.3·{15λB/(n-1)-2λB’/(n’-1)} (17)”。
And preferred above-mentioned formula (18) is following formula (18 '):
0.95·{5λB/(n-1)+2λB’/(n’-1)}＜dB(μm)＜1.4·{5λB/(n-1)+2λB’/(n’-1)} (18’)’，
More preferably above-mentioned formula (18) is following formula (18 "):
1.0·{5λB/(n-1)+2λB’/(n’-1)}≤dB(μm)＜1.4·{5λB/(n-1)+2λB’/(n’-1)}(18”)”。
And preferred above-mentioned formula (19) is following formula (19) ':
0.95·5λB/(n-1)＜dC(μm)＜1.4·5λB/(n-1) (19’)’，
More preferably above-mentioned formula (19) is following formula (19) ":
1.0·5λB/(n-1)≤d?C(μm)＜1.3·5λB/(n-1) (19”)”。
And preferred above-mentioned formula (20) is following formula (20) ':
0.95·{5λB/(n-1)-2λB’/(n’-1)}＜dD(μm)＜1.4·{5λB/(n-1)-2λB’/(n’-1)} (20’)’，
And preferred above-mentioned formula (20) is following formula (20) ":
1.0·{5λB/(n-1)-2λB’/(n’-1)}≤dD(μm)＜1.3·{5λB/(n-1)-2λB’/(n’-1)}(20”)”。
Wherein, λ B representes the design wavelength (μ m) of first light beam.Arbitrary value below above 0.410 (the μ m) of λ B ' expression 0.390 (μ m).The refractive index of the optical element when n representes wavelength X B.The refractive index of the optical element during n ' expression wavelength X B '.
For convenience's sake, when not knowing design wavelength, λ B can be regarded as with optical take-up apparatus in first light source that carries wavelength (μ m), promptly use wavelength identical.In addition, preferred λ B ' is the arbitrary value below above 0.405 (the μ m) of 0.390 (μ m).More preferably λ B ' is the arbitrary value below above 0.400 (the μ m) of 0.390 (μ m).
Step is meant that just optical path difference pays the length of the step of structure at optical axis direction.For example optical path difference is when to pay structure be structure as shown in Figure 7, and step just is meant other length of branch of d1, d2, d3, d4.So-called " first optical path difference pay structure step just have at least 2 kinds of steps height among following dA, dB, dC, the dD "; Be meant that first optical path difference pays the step of at least 1 step x in all steps of structure and just satisfy dA, dB, dC, dD any 1, the step of another step y just satisfies any one of the dA that is different from step x, dB, dC, dD at least.
Preferred first optical path difference is paid the step height that does not have in all steps of structure beyond dA, dB, dC, the dD.In addition, from making things convenient for mould manufacturing, good mould transfer printing property viewpoint, the height of preferred step is not too big.Therefore, more preferably first optical path difference is paid the step height that does not have in all steps of structure beyond dC and the dD.
In addition, it is wide all greater than 6 μ m that preferred at least the first optical path difference is paid the tooth pitch of structure.This structure can be lowered into the influence degree of transfer printing error of foozle and material of the mould of type object optical element, so can improve the utilization ratio of light, can on information recording surface, obtain higher spot intensity.And preferred at least the first optical path difference is paid structure, second optical path difference and is paid and construct and whole tooth pitches that the 3rd optical path difference is paid structure are wider than 6 μ m.Tooth pitch is wide to be meant optical axis vertical direction wide of the optical element of zonal structure.For example, optical path difference is paid structure when being structure as shown in Figure 7, wide w1, w2, w3, each length of w4 of being meant of tooth pitch.
And the tooth pitch that preferred first optical path difference is paid structure is wide all greater than 7 μ m, more preferably more than 10 μ m.In addition, preferred at least the first optical path difference is paid structure, second optical path difference and is paid and construct and whole tooth pitches that the 3rd optical path difference is paid structure are wider than 7 μ m, more preferably more than 10 μ m.In addition, preferably all tooth pitches are wide less than 100 μ m.
From the viewpoint of endless belt number, the endless belt number of preferred object optical element is below 140, more preferably below 120.Through reduce the number that the endless belt number can reduce the angle of endless belt as far as possible; Can reduce the influence degree of transfer printing error of foozle and material of the mould of moulding object optical element; So can improve the utilization ratio of light, can on information recording surface, obtain higher spot intensity.
To be used for being NA1, being that NA2 (NA1 >=NA2), is NA3 (NA2＞NA3) to the 3rd optical disc reproducing and/or the necessary object optical element of recorded information as the side numerical aperture as the side numerical aperture to the 1st optical disc reproducing and/or the necessary object optical element of recorded information to the 2nd optical disc reproducing and/or the necessary object optical element of recorded information as the side numerical aperture.Preferred NA1 is more than 0.8 below 0.9 or more than 0.55 below 0.7.Preferred NA2 is more than 0.55 below 0.7.Preferred NA3 is more than 0.4 below 0.55.
The middle section of preferred object optical element and the boundary of neighboring area are formed on the part of (more preferably more than the 0.95NA3, below the 1.15NA3) scope below the above 1.2NA3 of 0.9NA3 when being equivalent to the use of the 3rd light beam.More preferably the boundary of the middle section of object optical element and neighboring area is formed on the part that is equivalent to NA3.On the part of following (more preferably below the above 1.15NA2 of the 0.95NA2) scope of the above 1.2NA2 of 0.9NA2 when in addition, the boundary of the neighboring area of preferred object optical element and neighboring area is formed on and is equivalent to second light beam and uses.More preferably the boundary of the neighboring area of object optical element and neighboring area is formed on the part that is equivalent to NA2.The boundary in the most peripheral outside of preferred object optical element is formed on the part of (more preferably below the above 1.15NA1 of 0.95NA1) scope below the above 1.2NA1 of 0.9NA1 when being equivalent to the use of first light beam.More preferably the boundary in the most peripheral of the object optical element outside is formed on the part that is equivalent to NA1.
On the information recording surface of the 3rd CD the time, the preferred spheres surface aberration has the discontinuous portion in 1 place at least with the 3rd beam condenser that passes object optical element.At this moment, the scope of (more preferably the above 1.15NA3 of 0.95NA3 is following) below preferred discontinuous the above 1.2NA3 of 0.9NA3 when being present in the 3rd light beam and using.In addition, on the information recording surface of the 2nd CD the time, also the preferred spheres surface aberration has the discontinuous portion in 1 place at least with second beam condenser that passes object optical element.At this moment, the scope of (more preferably the above 1.1NA2 of 0.95NA2 is following) below preferred discontinuous the above 1.2NA2 of 0.9NA2 when being present in second light beam and using.
In addition; When spherical aberration does not have discontinuous continuously; With the 3rd beam condenser that passes object optical element on the information recording surface of the 3rd CD the time, the absolute value of longitudinal spherical aberration is more than the 0.03 μ m during preferred NA2, and the absolute value of longitudinal spherical aberration is below the 0.02 μ m during NA3.More preferably the absolute value of longitudinal spherical aberration is more than the 0.08 μ m during NA2, and the absolute value of longitudinal spherical aberration is below the 0.01 μ m during NA3.In addition, with second beam condenser that passes object optical element on the information recording surface of the 2nd CD the time, the absolute value of longitudinal spherical aberration is more than the 0.03 μ m during preferred NA1, and the absolute value of longitudinal spherical aberration is below the 0.005 μ m during NA2.
In addition, diffraction efficiency exists with ... the endless belt degree of depth of diffraction structure, so can suitably set the diffraction efficiency of middle section to each wavelength according to the purposes of optical take-up apparatus.For example, the 1st CD is write down and during the optical take-up apparatus of regenerating, the second, the 3rd CD only being regenerated, the diffraction efficiency that preferably makes middle section and/or neighboring area is that first light beam is paid attention to.Otherwise, the 1st CD only to be regenerated, the second, the 3rd CD is write down and during the optical take-up apparatus of regenerating, the diffraction efficiency that preferably makes middle section is that second, third light beam is paid attention to, the diffraction efficiency of neighboring area is that second light beam is paid attention to.
During any situation can through satisfy following conditional (11) come than the highland guarantee by each region area hamming calculate the diffraction efficiency of first light beam.
η11≤η21 (11)
Wherein, the diffraction efficiency of first light beam on the η 11 expression middle sections, the diffraction efficiency of first light beam on the η 21 expression neighboring areas.When the diffraction efficiency that makes middle section is second, third wavelength light beam attention; The diffraction efficiency step-down of first light beam of middle section; But; When the numerical aperture of the 1st CD was bigger than the numerical aperture of the 3rd CD, if consider the entire effective footpath of first light beam, then the diffraction efficiency of middle section reduces did not almost have too much influence.
Diffraction efficiency in this instructions can be as giving a definition: middle section and neighboring area are divided in (1), measure to have same focal point distance, lens thickness, numerical aperture, do not form the transmitance that first and second optical path difference is paid the object optical element of structure with same material formation.During mensuration, the transmitance of the light beam measurement middle section of neighboring area is incided in blocking, and the transmitance of the light beam measurement neighboring area of middle section is incided in blocking.(2) divide middle section and neighboring area, mensuration has the transmitance that first and second optical path difference is paid the object optical element of structure.(3) using the result of (1) to remove the result of above-mentioned (2), is each regional diffraction efficiency with the value that obtains.
In addition, can make first light beam to the, three light beams any two light beams the light utilization ratio more than 80%, the light utilization ratio of all the other light beams is more than 30% below 80%.The light utilization ratio that also can make all the other light beams is more than 40% below 70%.At this moment, preferably making the light utilization ratio is the 3rd light beam at the light beam of (or more than 40% below 70%) more than 30% below 80%.
Here said smooth utilization ratio; With: pay the object optical element (also can form the 3rd optical path difference and pay structure) that structure and second optical path difference are paid structure by having formed first optical path difference, the light quantity in the airy's disk of the optically focused spot that on the information recording surface of CD, forms is A; Form and first optical path difference that do not form with thickness on same focal length, the axle, numerical aperture, corrugated aberration is paid structure, second optical path difference and paid the object optical element that structure and the 3rd optical path difference are paid structure by same material, when the light quantity in the airy's disk of the optically focused spot that on the information recording surface of optical information recording medium, forms is B; Calculate with A/B.The airy's disk here is meant that the optical axis with the optically focused spot is the circle of radius centered r '.Use r '=0.61 λ/NA to represent.
In addition; Light quantity and the difference of light quantity of diffraction light that forms second pinpointed focus of diffraction light poor, that promptly form first pinpointed focus of light quantity of diffraction light of diffraction number of times of diffraction light and next big light quantity of diffraction number of times of maximum amount of passing the 3rd light beam that first optical path difference pays structure is more than 0% 20% when following; Tracking characteristics when keeping the 3rd CD well is difficulty especially; But, be exactly when this situation, the present invention also can keep tracking characteristics well.
The multiplying power m 1 of the object optical element of preferred first light beam satisfies following formula (2).Through satisfying this formula (2), can suppress the coma aberration of first light beam and the generation of astigmatism.
-0.01＜m1＜0.01 (2)。
More preferably satisfy following formula (2 ').More preferably m1=0.
-0.002＜m1＜0.002(2‘)。
In addition, the multiplying power m2 of the object optical element of preferred second light beam satisfies following formula (3):
-0.05＜m2≤0.002 (3)。
Making second light beam is directional light or when slightly directional light incides object optical element, preferred multiplying power m 2 satisfy following formula (3 '):
-0.002＜m2＜0.002?(3‘)。
And make second light beam is diverging light when inciding object optical element, and preferred multiplying power m2 satisfies following formula (3 ' '), more preferably satisfy following formula (3 ' ' '):
-0.05＜m2＜-0.002(3‘’)
-0.02≤m2≤-0.005(3‘’‘)。
In addition, the multiplying power m3 of the object optical element of preferred the 3rd light beam satisfies following formula (4):
-0.05＜m3＜0.00 (4)。
And preferred multiplying power m3 satisfies following formula (4 ' '), more preferably satisfy following formula (4 ' ' '):
-0.05＜m3＜-0.002(4‘’)
-0.02≤m3≤-0.005(4‘’‘)。
Especially satisfying formula (when the minimum tooth distance of 4 ' ' ') and object optical element is wider than 6 μ m; The divergence appropriateness of the 3rd light beam; So big coma takes place in the time of can preventing lens displacement, and, the mould foozle of moulding object optical element and the influence degree of material transferring error can be reduced; Can improve the utilization ratio of light, be very preferred mode.At this moment, more preferably satisfied above-mentioned formula (1 ').
In addition, through satisfying formula (5), so collimation lens in the time of can making second light beam and the 3rd light beam or coupled lens universalization are preferred.Especially preferred during by blocking at secondary light source and the 3rd light source.
-0.02＜m2-m3＜0.02 (5)。
Secondary light source and the 3rd light source more preferably satisfy formula (5 ') during by blocking.And secondary light source and the 3rd light source preferably satisfy above-mentioned formula (3 ' ' ' during by blocking simultaneously) and formula (5 ' ' ').
-0.002＜m2-m3＜0.002(5‘)。
Preferably satisfy following formula (5 ' ') in addition.More preferably satisfy formula (5 ' ' ').
0.005＜m1-m3＜0.05(5‘’)
0.005＜m1-m3＜0.025?(5‘’‘)。
In addition, when making object optical element be the individual plastic lens, also to make temperature characterisitic good even preferably how much sacrifice wavelength characteristic.Especially preferably keep the good balance of wavelength characteristic and temperature characterisitic.More preferably keep the record of the 1st CD and/or the temperature characterisitic in when regeneration.In order to satisfy this specific character, preferably satisfy following conditional (12) and (13):
+0.00045≤δSAT1/f(WFEλrms/(℃·mm))≤+0.0027 (12)
-0.045≤δSAλ/f(WFEλrms/(nm·mm))≤-0.0045 (13)。
Wherein, δ SAT1 is illustrated in the δ SA3/ δ T of object optical element when using wavelength (not following the wavelength variation of temperature variation with this moment) to carry out the 1st video disc recording and/or regeneration.Use wavelength to be meant the wavelength of the light source that is adopted in the optical take-up apparatus that has object optical element.Preferred use wavelength is the wavelength of the following scope of the above 415nm of 400nm, is to pass through the wavelength that object optical element carries out the 1st video disc recording and/or regeneration.Can not set as described above when using wavelength, can be with 405nm as using wavelength, try to achieve object optical element δ SAT1 and after state δ SAT2, δ SAT3.It is the rate of temperature change (temperature characterisitic) that δ SAT1 is meant 3 spherical aberrations of object optical element when using wavelength (not having wavelength variation) to carry out the 1st video disc recording and/or regeneration.WFE representes that 3 spherical aberrations show with the corrugated aberration.δ SA3/ δ λ when in addition, δ SA λ representes to use wavelength to carry out the 1st video disc recording and/or regeneration under the certain situation of environment temperature.It is the wavelength change rate (wavelength characteristic) that δ SA λ is meant 3 spherical aberrations of object optical element when using wavelength to carry out the 1st video disc recording and/or regeneration under the certain situation of environment temperature.The preferred ambient temperature is a room temperature.Room temperature is more than 10 ℃ below 40 ℃, preferably 25 ℃.The focal length of object optical element when f is meant the use wavelength (preferably 405nm) of first light beam.
More preferably satisfy following conditional (12 '):
+0.00091≤δSAT1/f(WFEλrms/(℃·m?m))≤+0.0018?(12‘)。
More preferably satisfy following conditional (12 ' '):
+0.0013≤δSAT1/f(WFEλrms/(℃·m?m))≤+0.0016(12‘’)。
Preferably satisfy following conditional (12 ' ' '):
|δSAT1|(WFEλrms/℃)≤0.002(12”’)。
Preferably satisfy in addition following conditional (13 '), more preferably satisfy following conditional (13 "):
-0.032≤δSAλ/f(WFEλrms/(nm·mm))≤-0.0091(13‘)
-0.015≤δSAλ/f(WFEλrms/(nm·mm))≤-0.011 (13”)。
Preferably satisfy following conditional (13 ' ") in addition: more preferably satisfy following conditional (13 " "):
0.01≤|δSAλ|(WFEλrms/nm)＜0.1(13”’)
0.02≤|δSAλ|(WFEλrms/nm)＜0.1(13””)。
Furtherly, preferred object optical element has the wavelength interdependence of following spherical aberration: with the wavelength change of first wavelength of following temperature variation, revise the variation that object optical element is followed the spherical aberration that the variations in refractive index of temperature variation causes.The formula that preferably meets the following conditions (14):
0≤δSAT2/f(WFEλrms/(℃·mm))≤+0.00136 (14)。
Wherein, δ SAT2 be illustrated in use wavelength (following the wavelength variation of temperature variation to be 0.05nm/ ℃) (being preferably 405nm) carry out the 1st CD record and/or when regeneration said object optical element δ SA3/ δ T.It is the rate of temperature change (temperature characterisitic) that δ SAT2 is meant 3 spherical aberrations of object optical element when using wavelength (following the wavelength variation of temperature variation to be 0.05nm/ ℃) to carry out the 1st video disc recording and/or regeneration.
More preferably satisfy following conditional (14 '):
0≤δSAT2/f(WFEλrms/(℃·mm))≤+0.00093?(14‘)。
More preferably satisfy following conditional (14 "):
+0.0007≤δSAT2/f(WFEλrms/(℃·mm))≤+0.0009 (14”)。
In addition, the light-gathering optics of optical take-up apparatus system has coupled lens such as collimation lens, when this coupled lens is plastic lens, and the formula that preferably meets the following conditions (15):
0≤δSAT3/f(WFEλrms/(℃·mm))≤+0.00091 (15)。
Wherein, δ SAT3 is illustrated in and uses wavelength (following the wavelength variation of temperature variation to be 0.05nm/ ℃) (being preferably 405nm) to carry out the record of the 1st CD and/or the δ SA3/ δ T of the optical system integral body that regeneration the time comprises coupled lens and object optical element.It is the rate of temperature change (temperature characterisitic) that δ SAT3 is meant 3 spherical aberrations of optical system integral body when using wavelength (following the wavelength variation of temperature variation to be 0.05nm/ ℃) to carry out the 1st video disc recording and/or regeneration.
More preferably satisfy following conditional (15 '):
0≤δSAT3/f(WFEλrms/(℃·mm))≤+0.00045(15‘)。
More preferably satisfy following conditional (15 "):
+0.00005≤δSAT3/f(WFEλrms/(℃·m?m))≤+0.0003 (15”)。
Preferably, satisfy above-mentioned conditional (12) to (15) through making object optical element have the temperature characterisitic correcting structure.For example, it is when having the situation of structure of the 3rd base configuration or the 7th base configuration at least that first optical path difference is paid structure, and optical element that needn't complex design just can realize satisfying above-mentioned conditional (12) to (15), so preferred.In addition; Second optical path difference pay structure be also needn't complex design when having the situation of any one structure of the 3rd base configuration, the 4th base configuration or the 7th base configuration at least optical element just can realize satisfying above-mentioned conditional (12), (12 '), (13), (13 '), (13 "), (14), (14 '), (14 ' '), (15), (15 '), (15 ' '), so preferred.In addition; Object optical element has the 3rd optical path difference and pays neighboring area, the 3rd optical path difference of structure to pay structure be when having the situation of any one structure of the 3rd base configuration, the 4th base configuration or the 7th base configuration at least having around the neighboring area; Optical element that also needn't complex design just can realize satisfying above-mentioned conditional (12), (12) ', (13), (13 '), (13 "), (14), (14 '), (14 ' '), (15), (15 '), (15 ' '), so preferred.
In addition; Object optical element more than 0.8 0.9 when following, satisfies above-mentioned conditional (12), (12 '), (13), (13 '), (13 "), (14), (more remarkable effect after 14 '), (14 ' '), (15), (15 '), (15 ' ') to the picture side numerical aperture (NA) of first light beam.
The operating distance of object lens (WD) is below the above 1.5mm of 0.20mm when in addition, preferably adopting the 3rd CD.Preferably below the above 1.00mm of 0.3mm.The WD of object lens is below the above 0.7mm of 0.4mm during its less preferred employing the 2nd CD.And the WD of object lens when t2 (t1＜preferably below the above 0.9mm of 0.6mm) below the above 0.9mm of 0.4mm when preferably adopting the 1st CD.
The entrance pupil footpath of object optical element; When adopting the 1st CD, preferably at
Figure GPA00001099152300431
more than the 2.8mm
Figure GPA00001099152300432
below the 4.5mm.
Optical information recording regenerator of the present invention has optical disc apparatus, wherein has above-mentioned optical take-up apparatus.
Optical disc apparatus to equipping in the optical information recording regenerator explains that optical disc apparatus has following manner: have only the dish that carries and can support CD, from taking in the optical information recording regenerator body of optical take-up apparatus etc., take out to the outside; Optical disc apparatus body together with taking in optical take-up apparatus etc. takes out to the outside.
Adopt in the optical information recording regenerator of above-mentioned modes, roughly equip following component parts, but be not limited to this: be incorporated in the optical take-up apparatus in shell etc.; The optical take-up apparatus drive sources such as recourse motor that optical take-up apparatus is moved to the interior week or the periphery of CD together with shell; The optical take-up apparatus that has the guided way etc. of in CD week or periphery direct light pick device shell is transferred means; Rotation drives the Spindle Motor of CD etc.
Except above-mentioned each component parts, also be provided with and carry and can support the dish of CD in the former mode, and be used for making loader mechanism that dish slides etc.; Not dish and loader mechanism in latter's mode, preferably each component parts is arranged on the base drawer that is equivalent to extract out to the outside.
The effect of invention
According to the present invention; A kind of optical take-up apparatus, object optical element and optical information recording regenerator can be provided; Wherein, on single lens, form optical path difference as object optical element and pay when structure, also can improve the utilization ratio of light; Can carry out information record and/or regeneration definitely to 3 kinds of different dishes of recording density such as high density compact disc, DVD, CD, can oversimplify and cost degradation by implementation structure.
Description of drawings
Fig. 1: the optical axis direction view of object optical element OBJ one example of the present invention.
Fig. 2: the optical path difference that object optical element OBJ of the present invention is provided with is paid the cross section pattern diagram of several examples (a)～(d) of structure.
Fig. 3: the formation generalized schematic of optical take-up apparatus of the present invention.
Fig. 4: the routine cross section pattern diagram of object optical element OBJ of the present invention.
Fig. 5: the longitudinal spherical aberration figure (a)～(c) of the BD of the embodiment of the invention 1, DVD, CD.
Fig. 6: the shape synoptic diagram of spot among the present invention.
Fig. 7: optical path difference is paid a routine cross section pattern diagram of structure.
Symbol description
AC two shaft drives
PPS polarization dichroism prism
The CL collimation lens
LD1 bluish violet semiconductor laser
The LM laser module
The OBJ object optical element
The PL1 protective substrate
The PL2 protective substrate
The PL3 protective substrate
The PU1 optical take-up apparatus
The RL1 information recording surface
The RL2 information recording surface
The RL3 information recording surface
The CN middle section
The MD neighboring area
The neighboring area of OT
Embodiment
A following preferred example with reference to the description of drawings embodiment of the present invention.Fig. 3 is the formation generalized schematic that can carry out this embodiment optical take-up apparatus PU1 of information record and/or regeneration to different discs BD, DVD, CD definitely.This optical take-up apparatus PU1 can be equipped on optical information recording regenerator.Here be that BD, the 2nd CD are that DVD, the 3rd CD are CD with the 1st CD.Yet the present invention is not limited to this embodiment.
Optical take-up apparatus PU1 has object optical element OBJ, aperture ST, collimation lens CL, polarization dichroism prism PPS, when BD is carried out the information recording/reproducing luminous ejaculation 405nm beam laser (first light beam) the first semiconductor laser LD1 (first light source) and accept the incorporate laser module LM of the catoptrical first photo detector PD1 etc. of BD information recording surface RL1.
The second semiconductor laser EP1 (secondary light source) of luminous ejaculation 658nm laser beam (second light beam) when laser module LM has DVD carried out the information recording/reproducing, when CD is carried out the information recording/reproducing luminous ejaculation 785nm laser beam (the 3rd light beam) the 3rd semiconductor laser EP2 (the 3rd light source), accept DVD information recording surface RL2 the catoptrical second photo detector DS1, accept catoptrical the 3rd photo detector DS2, the prism PS of CD information recording surface RL3.Be that secondary light source and the 3rd light source are by blocking.
Like Fig. 1 and shown in Figure 4, the object optical element OBJ of this embodiment, on the aspherics face of its light source side, to have formed be the middle section CN that contains optical axis, the neighboring area MD around it of centres circle shape with the optical axis, the neighboring area OT around it.Among Fig. 1 and Fig. 4, the ratios such as area of middle section, neighboring area, neighboring area do not have correct representation.
When BD used, first light beam incided on the object optical element OBJ with unlimited parallel beam state, and three light beam of second light beam of DVD when using during with the CD use is to incide on the object optical element OBJ with limited divergent beams state.Like this; Necessary aberration correction suppresses for less when CD DVD that can protective substrate thickness is different with BD, CD exchange use; State the optical path difference that is formed on the optical surface after the corresponding thus increase and pay the endless belt tooth pitch of structure (promptly reducing the power of diffraction structure); Foozle and the influence degree of transfer printing error of the mould of moulding object optical element OBJ can be suppressed like this, the light utilization ratio that approaches to design can be guaranteed.And the spot position of the 3rd light beam can be grown and guarantee operating distance away from object optical element OBJ.It is identical perhaps making operating distance, and correspondingly power does not need, and has to reduce the effect that optical path difference is paid structure endless belt tooth pitch.
In this embodiment; Because adopt the laser module LM of 2 laser, 1 plug-in unit; So can make the multiplying power of second light beam and the 3rd light beam of its ejaculation almost equal, still, kind that can corresponding for example CD; Through making collimation lens CL, be that limited divergent beams (or unlimited parallel beam) incide on the object optical element OBJ when DVD is used when being unlimited parallel beam (or limited divergent beams), CD use in the optical axis direction displacement.
First light beam (λ 1=405nm) divergent beams from bluish violet semiconductor laser LD1 ejaculation; See through polarization dichroism prism PPS; CL becomes parallel beam by collimation lens, is circular polarization by there not being illustrated λ/4 wave plates from the straight line polarisation transformation afterwards, and its beam diameter is by regulation through aperture ST; By the protective substrate PL1 of object optical element OBJ, on the information recording surface RL1 of BD, form spot via thickness 0.0875mm.
The folded light beam of on information recording surface RL1, modulating by information track; See through object optical element OBJ, aperture ST once more; Afterwards by there not being illustrated λ/4 wave plates to be transformed to the straight line polarization from circular polarization; CL becomes converging beam by collimation lens, sees through after the polarization dichroism prism PPS, brings together on the sensitive surface of the first photo detector PD1.Utilize the output signal of the first photo detector PD1, make object optical element OBJ focusing, follow the tracks of, can read BD thus and go up information recorded by 2 shaft drive AC.
Second light beam (λ 2=658nm) divergent beams from red semiconductor laser EP1 ejaculation; After prism PS is reflected; Reflect by polarization dichroism prism PPS; Becoming limited divergent beams by collimation lens CL, is circular polarization by there not being illustrated λ/4 wave plates from the straight line polarisation transformation afterwards, incides on the object optical element OJT.By the middle section of object optical element OBJ and neighboring area optically focused (light beam that passes neighboring area is by solar flareization; Form the spot periphery) light beam; Via thickness protective substrate PL2 O.6mm, become the spot on the information recording surface RL2 that is formed on DVD, form the spot central part.
The folded light beam of on information recording surface RL2, modulating by information track; See through object optical element OBJ, aperture ST once more; By there not being illustrated λ/4 wave plates to be transformed to the straight line polarization from circular polarization, CL becomes converging beam by collimation lens afterwards, after polarization dichroism prism PPS reflection; Afterwards in prism by after 2 secondary reflections, bring together in the second photo detector DS1.Utilize the output signal of the second photo detector DS1, can read DVD and go up information recorded.
The 3rd light beam (λ 3=785nm) divergent beams from infrared semiconductor laser EP2 ejaculation; After prism PS is reflected; Reflect by polarization dichroism prism PPS; Becoming limited divergent beams by collimation lens CL, is circular polarization by there not being illustrated λ/4 wave plates from the straight line polarisation transformation afterwards, incides on the object optical element OJT.(light beam that passes neighboring area and neighboring area is formed the spot periphery by solar flareization) light beam by the middle section optically focused of object optical element OBJ via the protective substrate PL3 of thickness 1.2mm, becomes the spot on the information recording surface RL3 that is formed on CD.
The folded light beam of on information recording surface RL3, modulating by information track; See through object optical element OBJ, aperture ST once more; By there not being illustrated λ/4 wave plates to be transformed to the straight line polarization from circular polarization, CL becomes converging beam by collimation lens afterwards, after polarization dichroism prism PPS reflection; Afterwards in prism by after 2 secondary reflections, bring together in the 3rd photo detector DS2.Utilize the output signal of the 3rd photo detector DS2, can read CD and go up information recorded.
When first light beam that penetrates from bluish violet semiconductor laser LD1 incides object optical element OBJ and goes up with parallel beam; Second optical path difference that first optical path difference of middle section is paid structure, neighboring area is paid the spherical aberration that first light beam is suitably revised in structure and neighboring area, can carry out information record and/or regeneration to the BD of protective substrate thickness t 1 definitely.In addition; When second light beam that penetrates from red semiconductor laser EP1 incides object optical element OBJ and goes up with parallel beam; Second optical path difference that first optical path difference of middle section is paid structure, neighboring area is paid structure and is suitably revised and result from wavelength difference and the spherical aberration of second light beam that produces of protective substrate difference in thickness and first light beam and second light beam of BD and DVD; The 3rd optical path difference of neighboring area is paid structure makes second light beam on the information recording surface of DVD, become solar flare, so can carry out information record and/or regeneration to the DVD of protective substrate thickness t 2 definitely.In addition; When the 3rd light beam that penetrates from infrared semiconductor laser EP2 incides object optical element OBJ and goes up with parallel beam; First optical path difference of middle section is paid structure and is suitably revised and result from wavelength difference and the spherical aberration of the 3rd light beam that produces of protective substrate difference in thickness and first light beam and the 3rd light beam of BD and CD; The 3rd optical path difference that second optical path difference of neighboring area is paid structure and neighboring area is paid structure makes the 3rd light beam on the information recording surface of CD, become solar flare, so can carry out information record and/or regeneration to the CD of protective substrate thickness t 3 definitely.In addition, first optical path difference of middle section is paid structure the optically focused spot of necessary light of the 3rd light beam that is used for record regenerating, and the not optically focused spot of light with the 3rd light beam draws back suitable distance just, the tracking characteristics in the time of like this can be well with CD.In addition, when because laser foozle etc. is former thereby during the wavelength departure reference wavelength, second optical path difference of neighboring area is paid structure can be to first light beam and the second light beam correction chromosphere surface aberration.
Embodiment
Subsequent explanation can be used in the embodiment of above-mentioned embodiment.Among the following embodiment 1, object optical element is polyolefins plastics simple lenses.Form first optical path difference on whole of object optical element optical surface middle section CN and paid structure.Form second optical path difference on whole of optical surface neighboring area MD and paid structure.Form the 3rd optical path difference on whole of the neighboring area OT of optical surface and paid structure.
Among the embodiment 1, it is the also overlapping structure of the 3rd base configuration except first base configuration, second base configuration that first optical path difference is paid structure, is the shape of two kinds of zigzag diffraction structures and scale-of-two tectonic stacking.Be first base configuration of zigzag diffraction structure, the light quantity of 2 diffraction lights that is designed to make the 1st light beam greater than the light quantity of 1 diffraction light of the light quantity of the diffraction light of other any number of times (also comprise 0 time, promptly see through light), the 2nd light beam greater than the light quantity of 1 diffraction light of the light quantity of the diffraction light of other any number of times (also comprise 0 time, promptly see through light), the 3rd light beam light quantity greater than the diffraction light of other any number of times (also comprise 0 time, promptly see through light).In addition; For second base configuration of scale-of-two structure is that so-called wavelength is selected diffraction structure, be designed to make the 1st light beam 0 diffraction light (seeing through light) light quantity greater than the light quantity of the light quantity of the diffraction light of other any number of times, 0 diffraction light of the 2nd light beam (seeing through light) greater than the light quantity of the diffraction light of other any number of times, the 3rd light beam ± light quantity of 1 diffraction light is greater than the light quantity of the diffraction light of other any number of times (also comprise 0 time, promptly see through light).Be the 3rd base configuration of zigzag diffraction structure, the light quantity of 10 diffraction lights that is designed to make the 1st light beam greater than the light quantity of 6 diffraction lights of the light quantity of the diffraction light of other any number of times (also comprise 0 time, promptly see through light), the 2nd light beam greater than the light quantity of 5 diffraction lights of the light quantity of the diffraction light of other any number of times (also comprise 0 time, promptly see through light), the 3rd light beam light quantity greater than the diffraction light of other any number of times (also comprise 0 time, promptly see through light).The step of the optical axis direction of first base configuration height is that the 1st light beam is provided optical path difference that summary 2 wavelength of the 1st wavelength divide, the 2nd light beam is provided optical path difference that summary 1.2 wavelength of the 2nd wavelength divide, the 3rd light beam provided the step height of the optical path difference that summary 1 wavelength of the 3rd wavelength divides.The step of the optical axis direction of second base configuration height is that the 1st light beam is provided optical path difference that summary 5 wavelength of the 1st wavelength divide, the 2nd light beam is provided optical path difference that summary 3 wavelength of the 2nd wavelength divide, the 3rd light beam provided the step height of the optical path difference that summary 2.5 wavelength of the 3rd wavelength divide.The step of the optical axis direction of the 3rd base configuration height is that the 1st light beam is provided optical path difference that summary 10 wavelength of the 1st wavelength divide, the 2nd light beam is provided optical path difference that summary 6 wavelength of the 2nd wavelength divide, the 3rd light beam provided the step height of the optical path difference that summary 5 wavelength of the 3rd wavelength divide.The 3rd base configuration is different with the female aspheric surface of the benchmark of first base configuration and second base configuration.
Among the embodiment 1; First optical path difference is paid structure shown in Fig. 2 (c); On the zone of middle section optical axis side, step is overlapping towards the hacksaw structure of optical axis side and scale-of-two structure, on the zone of middle section neighboring area side; Step is overlapping towards reverse hacksaw structure of optical axis side and scale-of-two structure, be provided with therebetween be used for switching the hacksaw structure step towards the transition zone of necessity.This transition zone showing with the optical path difference function when being attached to through the optical path difference on the corrugated by diffraction structure, is the zone that is equivalent to optical path difference extreme value of a function point.The optical path difference function is held extreme point, and the slope of optical path difference function diminishes, and can relax the endless belt tooth pitch, can suppress the transmitance that the shape error owing to diffraction structure causes and reduce.
Among the embodiment 1, it is the structure of overlapping first base configuration and the 4th base configuration that second optical path difference is paid structure, is zigzag diffraction structure and the thicker overlapping shape of zigzag diffraction structure.Cross sectional shape is the shape shown in Fig. 2 (d).Be first base configuration of zigzag diffraction structure, the light quantity of 2 diffraction lights that is designed to make the 1st light beam greater than the light quantity of 1 diffraction light of the light quantity of the diffraction light of other any number of times (also comprise 0 time, promptly see through light), the 2nd light beam greater than the light quantity of 1 diffraction light of the light quantity of the diffraction light of other any number of times (also comprise 0 time, promptly see through light), the 3rd light beam light quantity greater than the diffraction light of other any number of times (also comprise 0 time, promptly see through light).The step of the optical axis direction of the 4th base configuration height is that the 1st light beam is provided optical path difference that summary 5 wavelength of the 1st wavelength divide, the 2nd light beam is provided optical path difference that summary 3 wavelength of the 2nd wavelength divide, the 3rd light beam provided the step height of the optical path difference that summary 2.5 wavelength of the 3rd wavelength divide.And the 4th base configuration is different with the female aspheric surface of the benchmark of first base configuration.In addition, to pay the 4th base configuration that the 3rd base configuration and second optical path difference in the structure pay in the structure be continuous to first optical path difference.Be that first optical path difference is paid the 3rd base configuration in the structure its degree of depth is deepened gradually along with leaving optical axis; Pay structure since first optical path difference and pay the boundary of structure with second optical path difference, subsequent second optical path difference is paid the 4th base configuration structure that its degree of depth shoals gradually along with leaving optical axis in the structure.In addition, the light quantity of 5 diffraction lights that is designed to make the 1st light beam for the 4th base configuration of thick zigzag diffraction structure greater than the light quantity of 3 diffraction lights of the light quantity of the diffraction light of other any number of times, the 2nd light beam greater than the light quantity of 3 times and 2 times diffraction lights of the light quantity of the diffraction light of other any number of times, the 3rd light beam light quantity greater than the diffraction light of other any number of times (also comprise 0 time, promptly see through light).Understand for ease among Fig. 2 (c) and Fig. 2 (d) the pair cross-section shape done the exaggeration describe.
Among the embodiment 1, it is the structure that has only the 4th base configuration that the 3rd optical path difference is paid structure, is the shape of having only a kind of zigzag diffraction structure.The 3rd optical path difference is paid the 4th base configuration in the structure, is not along with leaving optical axis and go deep into the optical element inboard gradually in the optical axis vertical direction, is boundary with the somewhere, along with leaving optical axis to the structure in the optical element outside.
In table 1, show lens data.Below with the power multiplier of E (for example 2.5E-3) expression 10 (for example 2.5 * 10 -3).
The optical surface of object optical element be formed by in several 1 formulas respectively the regulation of the numerical expression of coefficient shown in the substitution table around the axisymmetric aspheric surface of optical axis.
[several 1]
X ( h ) = ( h 2 / r ) 1 + 1 - ( 1 + κ ) ( h / r ) 2 + Σ i = 0 10 A 2 i h 2i
Wherein, X (h) is the axle (with the direct of travel of light for just) of optical axis direction, and κ is the circular cone coefficient, A 2iBe the aspheric surface coefficient, h is the height that leaves optical axis.
In addition, the optical length that diffraction structure provides each wavelength light beam is stipulated by the numerical expression of coefficient shown in the substitution table in the optical path difference function of several 2 formulas.
[several 2]
Φ ( h ) = λ / λ B × dor × Σ i = 0 6 C 2 i h 2 i
Wherein, λ is the wavelength of incident beam, λ BBe to make wavelength (flame wavelength), dor is diffraction number of times, C 2iIt is the optical path difference function constant.
Embodiment 1
The lens data that shows embodiment 1 in the following table 1.Fig. 5 representes the longitudinal spherical aberration of embodiment 1.Fig. 5 (a) is BD side longitudinal spherical aberration figure, and Fig. 5 (b) is DVD side longitudinal spherical aberration figure, and Fig. 5 (c) is CD side longitudinal spherical aberration figure.1.0 expression NA0.85 or Ф 3.74mm of the longitudinal spherical aberration figure longitudinal axis.The multiplying power m1=0 of object optical element when BD uses, the multiplying power m2=-1/100 of object optical element when DVD uses, the multiplying power m3=-1/91 of object optical element when CD uses, so m2-m3=0.001, m1-m3=0.01.Among the embodiment 1, L=0.56mm.Therefore, L/f=0.56/2.5=0.224.In addition, the minimum tooth distance is wide to be 6.5 μ m, compares when all adopting directional light with the 1st, the 2nd, the 3rd light beam, can relax minimum tooth apart from wide.Therefore, the degree of influence of transfer printing error of foozle and material of the mould of moulding object optical element can be reduced,, higher spot intensity can be on information recording surface, obtained so can improve the utilization ratio of light.
Figure GPA00001099152300531
Figure GPA00001099152300541

Claims (40)

1. optical take-up apparatus has:
First light source penetrates first light beam of first wavelength X 1;
Secondary light source penetrates second light beam of second wavelength X 2;
The 3rd light source penetrates the 3rd light beam of wavelength lambda 3;
Object optical element, be used for making said first beam condenser on the information recording surface of the 1st CD with thickness t 1 protective substrate, make said second beam condenser on the information recording surface of the 2nd CD with thickness t 2 protective substrates, make said the 3rd beam condenser on the information recording surface of the 3rd CD with thickness t 3 protective substrates;
λ2＞λ1，λ3＞λ2，t1≤t2，t2＜t3，
Optical take-up apparatus is characterised in that,
Thereby said optical take-up apparatus through make said first beam condenser on the information recording surface of said the 1st CD, make said second beam condenser on the information recording surface of said the 2nd CD, make said the 3rd beam condenser on the information recording surface of said the 3rd CD, carry out information record and/or regeneration
The optical surface of said object optical element has two zones of the neighboring area of middle section and said its central area at least, and said middle section has first optical path difference and pays structure, and said neighboring area has second optical path difference and pays structure,
Said object optical element will pass said first light beam of the said middle section of said object optical element can information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD, will pass said second light beam of said middle section can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 2nd CD, will pass said the 3rd light beam of said middle section can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 3rd CD
Said object optical element will pass said first light beam of the said neighboring area of said object optical element can information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD, will pass said second light beam of said neighboring area can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 2nd CD
Form first pinpointed focus and second pinpointed focus by passing said the 3rd light beam that said first optical path difference of said object optical element pays structure; The light quantity of the light quantity of said first pinpointed focus and said second pinpointed focus is greater than the light quantity of other any spots of said the 3rd light beam formation
Said first pinpointed focus and said second pinpointed focus satisfy following formula (1), while and following formula (2)～(5) of satisfying relevant multiplying power:
0.05≤L/f≤0.35 (1)
-0.01＜m1＜0.01 (2)
-0.05＜m2≤0.002 (3)
-0.05＜m3＜-0.002 (4)
-0.02＜m2-m3≤0.02 (5)
Wherein,
F: when passing said the 3rd light beam that said first optical path difference pays structure and forming said first pinpointed focus, the focal length of said the 3rd light beam of said object optical element, the unit of f is mm,
L: the distance between said first pinpointed focus and said second pinpointed focus, the unit of L is mm,
M1: said object optical element is to the multiplying power of said first light beam;
M2: said object optical element is to the multiplying power of said second light beam;
M3: said object optical element is to the multiplying power of said the 3rd light beam,
Said the 3rd light beam incides on the said object optical element with the state of the limited divergent beams of satisfied (4).
2. like the optical take-up apparatus of record in 1 of the claim the, it is characterized in that, satisfy following formula (1):
0.05≤L/f≤0.25 (1)。
3. like the optical take-up apparatus of record in 1 of the claim the, it is characterized in that, be provided with the collimation lens that said second light beam and said the 3rd light beam pass jointly.
4. like the optical take-up apparatus of record in 1 of the claim the, it is characterized in that said secondary light source and said the 3rd light source are by blocking.
5. like the optical take-up apparatus of record in 1 of the claim the, it is characterized in that,
Pass in the spot that said the 3rd light beam of said object optical element forms on the information recording surface of said the 3rd CD; When optical axis direction is seen; From the spot center laterally successively; Formed the high spot central part of light quantity density, spot pars intermedia, light quantity density that light quantity density is lower than said spot central part is higher than the spot periphery that said spot pars intermedia is lower than said spot central part
Said spot central part is used to the information record and/or the regeneration of said the 3rd CD, and said spot pars intermedia and said spot periphery are not used in the information record and/or the regeneration of said the 3rd CD,
Pay said the 3rd light beam of structure by said second optical path difference of passing said object optical element, on the information recording surface of said the 3rd CD, form said spot periphery.
6. like the optical take-up apparatus of record in 1 of the claim the; It is characterized in that; The spot that the above the 3rd light beam of said first pinpointed focus forms is used for the record and/or the regeneration of said the 3rd CD, and the spot that the above the 3rd light beam of said second pinpointed focus forms is not used in the record and/or the regeneration of said the 3rd CD.
7. like the optical take-up apparatus of record in 1 of the claim the, it is characterized in that the optical surface of said object optical element around said neighboring area, has and has the neighboring area that the 3rd optical path difference is paid structure, has three zones.
8. like the optical take-up apparatus of record in 7 of the claims the; It is characterized in that; Said object optical element will pass said first light beam of the said neighboring area of said object optical element, can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD.
9. like the optical take-up apparatus of 1 record of claim the, it is characterized in that, satisfy-0.02≤m3≤-0.005, and the tooth pitch of the minimum of said object optical element is wider than 6 μ m.
10. like the optical take-up apparatus of 1 record of claim the, it is characterized in that said object optical element is a simple lens.
11. the optical take-up apparatus like record in 10 of the claims the is characterized in that said object optical element is a plastic lens.
12. an objective optical element for optical pickup device, this optical take-up apparatus has:
First light source penetrates first light beam of first wavelength X 1;
Secondary light source penetrates second light beam of second wavelength X 2;
The 3rd light source penetrates the 3rd light beam of wavelength lambda 3;
This optical take-up apparatus carries out information record and/or regeneration with said first light beam to the 1st CD with thickness t 1 protective substrate; With said second light beam the 2nd CD with thickness t 2 protective substrates is carried out information record and/or regeneration; With said the 3rd light beam the 3rd CD with thickness t 3 protective substrates is carried out information record and/or regeneration
λ2＞λ1，λ3＞λ2，t1≤t2，t2＜t3，
Objective optical element for optical pickup device is characterised in that,
The optical surface of said object optical element has two zones of the neighboring area of middle section and said its central area at least, and said middle section has first optical path difference and pays structure, and said neighboring area has second optical path difference and pays structure,
Said object optical element will pass said first light beam of the said middle section of said object optical element can information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD, will pass said second light beam of said middle section can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 2nd CD, will pass said the 3rd light beam of said middle section can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 3rd CD
Said object optical element will pass said first light beam of the said neighboring area of said object optical element can information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD, will pass said second light beam of said neighboring area can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 2nd CD
Form first pinpointed focus and second pinpointed focus by passing said the 3rd light beam that said first optical path difference of said object optical element pays structure; The light quantity of the light quantity of said first pinpointed focus and said second pinpointed focus is greater than the light quantity of other any spots of said the 3rd light beam formation
Said first pinpointed focus and said second pinpointed focus satisfy following formula (1), while and following formula (2)～(5) of satisfying relevant multiplying power:
0.05≤L/f≤0.35 (1)
-0.01＜m1＜0.01 (2)
-0.05＜m2≤0.002 (3)
-0.05＜m3＜-0.002 (4)
-0.02＜m2-m3≤0.02?(5)
Wherein,
F: when passing said the 3rd light beam that said first optical path difference pays structure and forming said first pinpointed focus, the focal length of said the 3rd light beam of said object optical element, the unit of f is mm,
L: the distance between said first pinpointed focus and said second pinpointed focus, the unit of L is mm,
M1: said object optical element is to the multiplying power of said first light beam;
M2: said object optical element is to the multiplying power of said second light beam;
M3: said object optical element is to the multiplying power of said the 3rd light beam,
Said the 3rd light beam incides on the said object optical element with the state of the limited divergent beams of satisfied (4).
13. the objective optical element for optical pickup device like record in 12 of the claims the is characterized in that, satisfies following formula (1):
0.05≤L/f≤0.25 (1)。
14. the objective optical element for optical pickup device like record in 12 of the claims the is characterized in that, is provided with the collimation lens that said second light beam and said the 3rd light beam pass jointly.
15. the objective optical element for optical pickup device like record in 12 of the claims the is characterized in that said secondary light source and said the 3rd light source are by blocking.
16. the objective optical element for optical pickup device like record in 12 of the claims the is characterized in that,
On the position that forms said first pinpointed focus; In the spot that forms by said the 3rd light beam that passes said object optical element; When optical axis direction is seen; From the spot center laterally successively, formed the high spot central part of light quantity density, spot pars intermedia, light quantity density that light quantity density is lower than said spot central part is higher than the spot periphery that said spot pars intermedia is lower than said spot central part
Said the 3rd light beam of being paid structure by said second optical path difference of passing said object optical element forms said spot periphery.
17. the objective optical element for optical pickup device like record in 12 of the claims the is characterized in that, said object optical element has and has the neighboring area that the 3rd optical path difference is paid structure around said neighboring area.
18. objective optical element for optical pickup device like record in 17 of the claims the; It is characterized in that; Said object optical element will pass said first light beam of the said neighboring area of said object optical element, can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD.
19. the objective optical element for optical pickup device like record in 12 of the claims the is characterized in that the tooth pitch of the minimum of said object optical element is wider than 6 μ m.
20. the objective optical element for optical pickup device like record in 12 of the claims the is characterized in that said object optical element is a simple lens.
21. the objective optical element for optical pickup device like record in 20 of the claims the is characterized in that said object optical element is a plastic lens.
22. an optical information recording regenerator has optical take-up apparatus, this optical take-up apparatus has: first light source that penetrates first light beam of first wavelength X 1; Penetrate the secondary light source of second light beam of second wavelength X 2; Penetrate the 3rd light source of the 3rd light beam of wavelength lambda 3; Be used for making said first beam condenser on the 1st optical disc information record surface with thickness t 1 protective substrate, make said second beam condenser on the 2nd optical disc information record surface with thickness t 2 protective substrates, make the object optical element of said the 3rd beam condenser on the 3rd optical disc information record surface with thickness t 3 protective substrates; Thereby said optical take-up apparatus through make said first beam condenser on the information recording surface of said the 1st CD, make said second beam condenser on the information recording surface of said the 2nd CD, make said the 3rd beam condenser on the information recording surface of said the 3rd CD, carry out information record and/or regeneration
λ2＞λ1，λ3＞λ2，t1≤t2，t2＜t3，
Optical information recording regenerator is characterised in that,
The optical surface of said object optical element has two zones of the neighboring area of middle section and said its central area at least, and said middle section has first optical path difference and pays structure, and said neighboring area has second optical path difference and pays structure,
Said object optical element will pass said first light beam of the said middle section of said object optical element can information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD, will pass said second light beam of said middle section can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 2nd CD, will pass said the 3rd light beam of said middle section can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 3rd CD
Said object optical element will pass said first light beam of the said neighboring area of said object optical element can information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD, will pass said second light beam of said neighboring area can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 2nd CD
Form first pinpointed focus and second pinpointed focus by passing said the 3rd light beam that said first optical path difference of said object optical element pays structure; The light quantity of the light quantity of said first pinpointed focus and said second pinpointed focus is greater than the light quantity of other any spots of said the 3rd light beam formation
Said first pinpointed focus and said second pinpointed focus satisfy following formula (1), while and following formula (2)～(5) of satisfying relevant multiplying power:
0.05≤L/f≤0.35 (1)
-0.01＜m1＜0.01 (2)
-0.05＜m2≤0.002 (3)
-0.05＜m3＜-0.002 (4)
-0.02＜m2-m3≤0.02 (5)
Wherein,
F: when passing said the 3rd light beam that said first optical path difference pays structure and forming said first pinpointed focus, the focal length of said the 3rd light beam of said object optical element, the unit of f is mm,
L: the distance between said first pinpointed focus and said second pinpointed focus, the unit of L is mm,
M1: said object optical element is to the multiplying power of said first light beam;
M2: said object optical element is to the multiplying power of said second light beam;
M3: said object optical element is to the multiplying power of said the 3rd light beam,
Said the 3rd light beam incides on the said object optical element with the state of the limited divergent beams of satisfied (4).
23. the optical information recording regenerator like record in 22 of the claims the is characterized in that,
Pass in the spot that said the 3rd light beam of said object optical element forms on the information recording surface of said the 3rd CD; When optical axis direction is seen; From the spot center laterally successively; Formed the high spot central part of light quantity density, spot pars intermedia, light quantity density that light quantity density is lower than said spot central part is higher than the spot periphery that said spot pars intermedia is lower than said spot central part
Said spot central part is used to the information record and/or the regeneration of said the 3rd CD, and said spot pars intermedia and said spot periphery are not used in the information record and/or the regeneration of said the 3rd CD,
By passing said the 3rd light beam that said second optical path difference of said object optical element is paid structure, on the information recording surface of said the 3rd CD, form said spot periphery.
24. an optical take-up apparatus has: first light source that penetrates first light beam of first wavelength X 1; Penetrate the secondary light source of second light beam of second wavelength X 2; Penetrate the 3rd light source of the 3rd light beam of wavelength lambda 3; Be used for making said first beam condenser on the 1st optical disc information record surface with thickness t 1 protective substrate, make said second beam condenser on the 2nd optical disc information record surface with thickness t 2 protective substrates, make the object optical element of said the 3rd beam condenser on the 3rd optical disc information record surface with thickness t 3 protective substrates; Thereby through make said first beam condenser on the information recording surface of said the 1st CD, make said second beam condenser on the information recording surface of said the 2nd CD, make said the 3rd beam condenser on the information recording surface of said the 3rd CD, carry out information record and/or regeneration
λ2＞λ1，λ3＞λ2，t1≤t2，t2＜t3，
The optical surface of said object optical element has two zones of the neighboring area of middle section and said its central area at least, and said middle section has first optical path difference and pays structure, and said neighboring area has second optical path difference and pays structure,
Said object optical element will pass said first light beam of the said middle section of said object optical element can information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD, will pass said second light beam of said middle section can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 2nd CD, will pass said the 3rd light beam of said middle section can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 3rd CD
Said object optical element will pass said first light beam of the said neighboring area of said object optical element can information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD, will pass said second light beam of said neighboring area can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 2nd CD
It is overlapping first base configuration and second base configuration and the structure that constitutes at least that said first optical path difference is paid structure,
Said first base configuration is to make 2 diffraction light quantities of said first light beam that passes said first base configuration pay structure greater than 1 diffraction light quantity of the diffraction light quantity of other any number of times, said the 3rd light beam greater than the optical path difference of the diffraction light quantity of other any number of times greater than 1 diffraction light quantity of the diffraction light quantity of other any number of times, said second light beam
Said second base configuration be 0 diffraction light quantity making said first light beam that passes said second base configuration greater than 0 diffraction light quantity of the diffraction light quantity of other any number of times, said second light beam greater than the diffraction light quantity of other any number of times, said the 3rd light beam ± 1 time the diffraction light quantity is paid structure greater than the optical path difference of the diffraction light quantity of other any number of times, and satisfies following formula (2)～(5) of relevant multiplying power:
-0.01＜m1＜0.01 (2)
-0.05＜m2≤0.002 (3)
-0.05＜m3＜-0.002?(4)
-0.02＜m2-m3≤0.02(5)
Wherein,
M1: said object optical element is to the multiplying power of said first light beam;
M2: said object optical element is to the multiplying power of said second light beam;
M3: said object optical element is to the multiplying power of said the 3rd light beam,
Said the 3rd light beam incides on the said object optical element with the state of the limited divergent beams of satisfied (4).
25. the optical take-up apparatus like record in 24 of the claims the is characterized in that,
It is any one structure that has said first base configuration, the 5th base configuration or the 6th base configuration at least that said second optical path difference is paid structure,
Said the 5th base configuration is to make 1 diffraction light quantity of said first light beam that passes said the 5th base configuration pay structure greater than 1 diffraction light quantity of the diffraction light quantity of other any number of times, said the 3rd light beam greater than the optical path difference of the diffraction light quantity of other any number of times greater than 1 diffraction light quantity of the diffraction light quantity of other any number of times, said second light beam
Said the 6th base configuration is to make 3 diffraction light quantities of said first light beam that passes said the 6th base configuration pay structure greater than 2 diffraction light quantities of the diffraction light quantity of other any number of times, said the 3rd light beam greater than the optical path difference of the diffraction light quantity of other any number of times greater than 2 diffraction light quantities of the diffraction light quantity of other any number of times, said second light beam.
26. the optical take-up apparatus like record in 24 of the claims the is characterized in that the tooth pitch of the minimum of said object optical element is wider than 6 μ m.
27. the optical take-up apparatus like record in 24 of the claims the is characterized in that said object optical element is a simple lens.
28. the optical take-up apparatus like record in 27 of the claims the is characterized in that said object optical element is a plastic lens.
29. the optical take-up apparatus like record in 24 of the claims the is characterized in that,
It is except said first base configuration and said second base configuration and any one structure of overlapping the 3rd base configuration or the 7th base configuration that said first optical path difference is paid structure,
Said the 3rd base configuration is to make 10 diffraction light quantities of said first light beam that passes said the 3rd base configuration pay structure greater than 5 diffraction light quantities of the diffraction light quantity of other any number of times, said the 3rd light beam greater than the optical path difference of the diffraction light quantity of other any number of times greater than 6 diffraction light quantities of the diffraction light quantity of other any number of times, said second light beam
Said the 7th base configuration is to make 2 diffraction light quantities of said first light beam that passes said the 7th base configuration pay structure greater than 1 diffraction light quantity of the diffraction light quantity of other any number of times, said the 3rd light beam greater than the optical path difference of the diffraction light quantity of other any number of times greater than 1 diffraction light quantity of the diffraction light quantity of other any number of times, said second light beam.
30. the optical take-up apparatus like record in 29 of the claims the is characterized in that,
It is except any one of said first base configuration, said the 5th base configuration or said the 6th base configuration that said second optical path difference is paid structure; And the overlapping any one structure of said the 3rd base configuration, the 4th base configuration or the 7th base configuration
Said the 4th base configuration is to make 5 diffraction light quantities of said first light beam that passes said the 4th base configuration pay structure greater than 2 diffraction light quantities of the diffraction light quantity of other any number of times, said the 3rd light beam greater than the optical path difference of the diffraction light quantity of other any number of times greater than 3 diffraction light quantities of the diffraction light quantity of other any number of times, said second light beam.
31. the optical take-up apparatus like record in 30 of the claims the is characterized in that,
The optical surface of said object optical element has around said neighboring area and has the neighboring area that the 3rd optical path difference is paid structure,
With said first light beam that passes the said neighboring area of said object optical element can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD,
It is any one structure that has said the 3rd base configuration, said the 4th base configuration or the 7th base configuration at least that said the 3rd optical path difference is paid structure.
32. an objective optical element for optical pickup device, this optical take-up apparatus has: first light source, penetrate first light beam of first wavelength X 1; Secondary light source penetrates second light beam of second wavelength X 2; The 3rd light source penetrates the 3rd light beam of wavelength lambda 3; Optical take-up apparatus carries out information record and/or regeneration with said first light beam to the 1st CD with thickness t 1 protective substrate; With said second light beam the 2nd CD with thickness t 2 protective substrates is carried out information record and/or regeneration; With said the 3rd light beam the 3rd CD with thickness t 3 protective substrates is carried out information record and/or regeneration
λ2＞λ1，λ3＞λ2，t1≤t2，t2＜t3，
Objective optical element for optical pickup device is characterised in that,
The optical surface of said object optical element has two zones of the neighboring area of middle section and said its central area at least, and said middle section has first optical path difference and pays structure, and said neighboring area has second optical path difference and pays structure,
Said object optical element will pass said first light beam of the said middle section of said object optical element can information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD, will pass said second light beam of said middle section can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 2nd CD, will pass said the 3rd light beam of said middle section can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 3rd CD
Said object optical element will pass said first light beam of the said neighboring area of said object optical element can information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD, will pass said second light beam of said neighboring area can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 2nd CD
It is overlapping first base configuration and second base configuration and the structure that constitutes at least that said first optical path difference is paid structure,
Said first base configuration is to make 2 diffraction light quantities of said first light beam that passes said first base configuration pay structure greater than 1 diffraction light quantity of the diffraction light quantity of other any number of times, said the 3rd light beam greater than the optical path difference of the diffraction light quantity of other any number of times greater than 1 diffraction light quantity of the diffraction light quantity of other any number of times, said second light beam
Said second base configuration be 0 diffraction light quantity making said first light beam that passes said second base configuration greater than 0 diffraction light quantity of the diffraction light quantity of other any number of times, said second light beam greater than the diffraction light quantity of other any number of times, said the 3rd light beam ± 1 time the diffraction light quantity is paid structure greater than the optical path difference of the diffraction light quantity of other any number of times, and satisfies following formula (2)～(5) of relevant multiplying power:
-0.01＜m1＜0.01 (2)
-0.05＜m2≤0.002 (3)
-0.05＜m3＜-0.002?(4)
-0.02＜m2-m3≤0.02(5)
Wherein,
M1: said object optical element is to the multiplying power of said first light beam;
M2: said object optical element is to the multiplying power of said second light beam;
M3: said object optical element is to the multiplying power of said the 3rd light beam,
Said the 3rd light beam incides on the said object optical element with the state of the limited divergent beams of satisfied (4).
33. the objective optical element for optical pickup device like record in 32 of the claims the is characterized in that,
It is any one structure that has said first base configuration, the 5th base configuration or the 6th base configuration at least that said second optical path difference is paid structure,
Said the 5th base configuration is to make 1 diffraction light quantity of said first light beam that passes said the 5th base configuration pay structure greater than 1 diffraction light quantity of the diffraction light quantity of other any number of times, said the 3rd light beam greater than the optical path difference of the diffraction light quantity of other any number of times greater than 1 diffraction light quantity of the diffraction light quantity of other any number of times, said second light beam
Said the 6th base configuration is to make 3 diffraction light quantities of said first light beam that passes said the 6th base configuration pay structure greater than 2 diffraction light quantities of the diffraction light quantity of other any number of times, said the 3rd light beam greater than the optical path difference of the diffraction light quantity of other any number of times greater than 2 diffraction light quantities of the diffraction light quantity of other any number of times, said second light beam.
34. the objective optical element for optical pickup device like record in 32 of the claims the is characterized in that, satisfy-0.02≤m3≤-0.005, and the tooth pitch of the minimum of said object optical element is wider than 6 μ m.
35. the objective optical element for optical pickup device like record in 32 of the claims the is characterized in that said object optical element is a simple lens.
36. the objective optical element for optical pickup device like record in 35 of the claims the is characterized in that said object optical element is a plastic lens.
37. the objective optical element for optical pickup device like record in 32 of the claims the is characterized in that,
It is except said first base configuration and said second base configuration and any one structure of overlapping the 3rd base configuration or the 7th base configuration that said first optical path difference is paid structure,
Said the 3rd base configuration is to make 10 diffraction light quantities of said first light beam that passes said the 3rd base configuration pay structure greater than 5 diffraction light quantities of the diffraction light quantity of other any number of times, said the 3rd light beam greater than the optical path difference of the diffraction light quantity of other any number of times greater than 6 diffraction light quantities of the diffraction light quantity of other any number of times, said second light beam
Said the 7th base configuration is to make 2 diffraction light quantities of said first light beam that passes said the 7th base configuration pay structure greater than 1 diffraction light quantity of the diffraction light quantity of other any number of times, said the 3rd light beam greater than the optical path difference of the diffraction light quantity of other any number of times greater than 1 diffraction light quantity of the diffraction light quantity of other any number of times, said second light beam.
38. the objective optical element for optical pickup device like record in 37 of the claims the is characterized in that,
It is except any one of said first base configuration, said the 5th base configuration or said the 6th base configuration that said second optical path difference is paid structure; And the overlapping any one structure of said the 3rd base configuration, the 4th base configuration or the 7th base configuration
Said the 4th base configuration is to make 5 diffraction light quantities of said first light beam that passes said the 4th base configuration pay structure greater than 2 diffraction light quantities of the diffraction light quantity of other any number of times, said the 3rd light beam greater than the optical path difference of the diffraction light quantity of other any number of times greater than 3 diffraction light quantities of the diffraction light quantity of other any number of times, said second light beam.
39. the objective optical element for optical pickup device like record in 38 of the claims the is characterized in that,
The optical surface of said object optical element has around said neighboring area and has the neighboring area that the 3rd optical path difference is paid structure,
With said first light beam that passes the said neighboring area of said object optical element can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD,
It is any one structure that has said the 3rd base configuration, said the 4th base configuration or the 7th base configuration at least that said the 3rd optical path difference is paid structure.
40. an optical information recording regenerator has optical take-up apparatus, this optical take-up apparatus has: first light source, penetrate first light beam of first wavelength X 1; Secondary light source penetrates second light beam of second wavelength X 2; The 3rd light source penetrates the 3rd light beam of wavelength lambda 3; Be used for making said first beam condenser on the 1st optical disc information record surface with thickness t 1 protective substrate, make said second beam condenser on the 2nd optical disc information record surface with thickness t 2 protective substrates, make the object optical element of said the 3rd beam condenser on the 3rd optical disc information record surface with thickness t 3 protective substrates; Said optical take-up apparatus through make said first beam condenser on the information recording surface of said the 1st CD, make said second beam condenser on the information recording surface of said the 2nd CD, make said the 3rd beam condenser on the information recording surface of said the 3rd CD; Thereby the information of carrying out record and/or regeneration
λ2＞λ1，λ3＞λ2，t1≤t2，t2＜t3，
Optical information recording regenerator is characterised in that,
The optical surface of said object optical element has two zones of the neighboring area of middle section and said its central area at least, and said middle section has first optical path difference and pays structure, and said neighboring area has second optical path difference and pays structure,
Said object optical element will pass said first light beam of the said middle section of said object optical element can information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD, will pass said second light beam of said middle section can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 2nd CD, will pass said the 3rd light beam of said middle section can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 3rd CD
Said object optical element will pass said first light beam of the said neighboring area of said object optical element can information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 1st CD, will pass said second light beam of said neighboring area can the information record and/or again the dried rhizome of rehmannia be concentrated on the information recording surface of said the 2nd CD
It is overlapping first base configuration and second base configuration and the structure that constitutes at least that said first optical path difference is paid structure,
Said first base configuration is to make 2 diffraction light quantities of said first light beam that passes said first base configuration pay structure greater than 1 diffraction light quantity of the diffraction light quantity of other any number of times, said the 3rd light beam greater than the optical path difference of the diffraction light quantity of other any number of times greater than 1 diffraction light quantity of the diffraction light quantity of other any number of times, said second light beam
Said second base configuration be 0 diffraction light quantity making said first light beam that passes said second base configuration greater than 0 diffraction light quantity of the diffraction light quantity of other any number of times, said second light beam greater than the diffraction light quantity of other any number of times, said the 3rd light beam ± 1 time the diffraction light quantity is paid structure greater than the optical path difference of the diffraction light quantity of other any number of times, and satisfies following formula (2)～(5) of relevant multiplying power:
-0.01＜m1＜0.01 (2)
-0.05＜m2≤0.002 (3)
-0.05＜m3＜-0.002?(4)
-0.02＜m2-m3≤0.02(5)
Wherein,
M1: said object optical element is to the multiplying power of said first light beam;
M2: said object optical element is to the multiplying power of said second light beam;
M3: said object optical element is to the multiplying power of said the 3rd light beam,
Said the 3rd light beam incides on the said object optical element with the state of the limited divergent beams of satisfied (4).
CN2008801118126A 2007-10-18 2008-10-02 Optical pickup device, objective optical element for optical pickup device and optical information recorder/reproducer Expired - Fee Related CN101828225B (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP2007271398 2007-10-18
JP271398/07 2007-10-18
PCT/JP2008/067918 WO2009051019A1 (en) 2007-10-18 2008-10-02 Optical pickup device, objective optical element for optical pickup device and optical information recorder/reproducer

Publications (2)

Publication Number Publication Date
CN101828225A CN101828225A (en) 2010-09-08
CN101828225B true CN101828225B (en) 2012-03-28

Family

ID=40567291

Family Applications (1)

Application Number Title Priority Date Filing Date
CN2008801118126A Expired - Fee Related CN101828225B (en) 2007-10-18 2008-10-02 Optical pickup device, objective optical element for optical pickup device and optical information recorder/reproducer

Country Status (3)

Country Link
JP (1) JPWO2009051019A1 (en)
CN (1) CN101828225B (en)
WO (1) WO2009051019A1 (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2012029581A1 (en) * 2010-08-31 2012-03-08 コニカミノルタオプト株式会社 Object lens and optical pickup device

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101034570A (en) * 2006-03-07 2007-09-12 柯尼卡美能达精密光学株式会社 Optical pickup apparatus, objective optical element and optical information recording reproducing apparatus

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4384555B2 (en) * 2003-06-17 2009-12-16 Ｈｏｙａ株式会社 Objective lens for optical pickup and optical pickup device
JP4033240B2 (en) * 2006-03-07 2008-01-16 コニカミノルタオプト株式会社 Optical pickup device, objective optical element, and optical information recording / reproducing device

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101034570A (en) * 2006-03-07 2007-09-12 柯尼卡美能达精密光学株式会社 Optical pickup apparatus, objective optical element and optical information recording reproducing apparatus
CN101034571A (en) * 2006-03-07 2007-09-12 柯尼卡美能达精密光学株式会社 Optical pickup apparatus, objective optical element and optical information recording reproducing apparatus

Also Published As

Publication number Publication date
JPWO2009051019A1 (en) 2011-03-03
CN101828225A (en) 2010-09-08
WO2009051019A1 (en) 2009-04-23

Similar Documents

Publication Publication Date Title
CN102246233B (en) Objective optical element and optical pickup device
CN100479041C (en) Optical pickup apparatus and diffractive optical element for optical pickup apparatus
CN100449622C (en) Objective optical system, optical pickup apparatus and optical information recording/reproducing apparatus
CN101669171B (en) Optical pickup device and objective optical element
JP4076047B2 (en) Objective lens for optical recording medium and optical pickup device using the same
CN102037512B (en) Objective lens and optical pick-up device
CN102067215A (en) Objective lens, optical pickup device, and optical disk drive
CN101971257B (en) Objective lens and optical pickup apparatus
JP4483864B2 (en) Objective optical system, optical pickup device, and optical disk drive device
JP2005259332A (en) Optical pickup apparatus and diffractive optical element for same
CN100555427C (en) Optical take-up apparatus and optical element thereof, object optical element
CN101809662B (en) Objective lens for optical pickup device, and optical pickup device
CN1910670B (en) Objective optical element and optical pickup device
KR20020037691A (en) Objective lens for optical pickup apparatus and optical pickup apparatus
CN101421787A (en) Optical pickup device, optical information recording and reproducing device and design, method of optical element
CN101828225B (en) Optical pickup device, objective optical element for optical pickup device and optical information recorder/reproducer
JP2009129515A (en) Objective optical element and optical pickup device
JP2009110591A (en) Objective lens and optical pickup device
CN101681645B (en) Objective optical element for optical pickup device and optical pickup device
CN102007538A (en) Objective lens and optical pickup device
JP4385902B2 (en) Objective optical element and optical pickup device
JP2005166173A (en) Optical pickup device and optical information recording/reproducing device
CN102292770A (en) Objective lens and optical pickup device
JP2009037717A (en) Objective optical element and optical pickup device
CN101809663A (en) Objective lens and optical pickup device

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C14 Grant of patent or utility model
GR01 Patent grant
C17 Cessation of patent right
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20120328

Termination date: 20131002