CN1332386C - Optical reading head - Google Patents
Optical reading head Download PDFInfo
- Publication number
- CN1332386C CN1332386C CNB2004100683584A CN200410068358A CN1332386C CN 1332386 C CN1332386 C CN 1332386C CN B2004100683584 A CNB2004100683584 A CN B2004100683584A CN 200410068358 A CN200410068358 A CN 200410068358A CN 1332386 C CN1332386 C CN 1332386C
- Authority
- CN
- China
- Prior art keywords
- plane
- wedge shape
- optical sheet
- optical
- laser beam
- 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
Links
Images
Landscapes
- Optical Head (AREA)
Abstract
The present invention relates to an optical reading head which comprises a laser light source, a spectroscope, a collimating lens, a plane reflector, a focusing lens, a first wedge-shaped optical plate, a second wedge-shaped optical plate, an optical plate positioning module and an optical detector, wherein the first wedge-shaped optical plate is provided with a first plane and a first bevel which are not mutually parallel, the second wedge-shaped optical plate is provided with a second plane and a second bevel which are not mutually parallel, and the first bevel faces the second bevel to make the first plane parallel to the second plane. Therefore, first laser light emitted from the laser light source can be focused in an optical recording medium after the first laser light passes through the first wedge-shaped optical plate and the second wedge-shaped optical plate.
Description
Technical field
The present invention relates to a kind of optical read head, particularly a kind of have optical sheet to revise the optical read head of aberration.
Background technology
Along with the progress of science and technology, the capacity of all types of recording mediums is increasing, and wherein optical record medium strengthens its storage volume by shortening the laser light wavelength, strengthen object lens NA and increasing recording layer.In the method for these three kinds increase optical record medium capacity, the most surprising with the increase capacity effect that increases recording layer again.Yet these the three kinds methods that increase capacity all can be deepened aberration, increasing recording layer, when laser reads the recording layer of different-thickness the optical path of process is different can produce reading of different aberration effects data.So, among optical read head, must add the influence that a suitable mechanism just can alleviate aberration, thereby improve degree of accuracy and accuracy that optical read head reads the optical record medium of pluratity of recording layers.
Shown in Figure 1A; one optical record medium 15 comprises one first recording layer 151, an overlayer 152, one second recording layer 153, a substrate 154 and a protective seam 155; one laser beam 11 passes first recording layer 151 that focuses on optical record medium 15 behind the condenser lens 12; this moment, condenser lens 12 was done the correction of aberration optimization at the thickness of first recording layer 151 in order to alleviate the influence of aberration.Yet, if laser beam 11 must have a correction mechanism to alleviate the influence of aberration when reading second recording layer 153.
Shown in Figure 1B, one optical sheet locating module 14 with an optical sheet 13 suitably dislocation between condenser lens 12 and optical record medium 15, make laser beam 11 pass second recording layer 153 that focuses on optical record medium 15 behind condenser lens 12 and the optical sheet 13, and with the aberration correction to minimum.This kind changed the method that suitable optical sheet is revised aberration at the recording layer of different-thickness, if the many more aberrations that also need many more optical sheets to revise the different recording layer of recording layer, and cause the design difficulty of optical read head and the increase of cost.
In view of this, how to provide a kind of optical read head, in the hope of the optical record medium that can read pluratity of recording layers and alleviate the aberration that produces when reading the different recording layer, one of current just important topic.
Summary of the invention
Because above-mentioned problem the objective of the invention is to overcome the deficiencies in the prior art and defective, provide a kind of optical read head that can suitably revise the light path of laser beam process.
For reaching above-mentioned purpose, the invention provides a kind of optical read head, comprise a LASER Light Source, a spectroscope, collimation lens, a plane mirror, a condenser lens, one first wedge shape optical sheet, one second wedge shape optical sheet, an optical sheet locating module and a photodetector.In the present invention, LASER Light Source is launched one first laser beam, spectroscope separates with first laser beam and by one second laser beam that an optical record medium is passed back, collimation lens collimates first laser beam, first laser beam that the plane reflection mirror reflection is transmitted by collimation lens, condenser lens focus in the optical record medium first laser beam; In addition, the first wedge shape optical sheet has one first plane and one first inclined-plane that is not parallel to each other, and the second wedge shape optical sheet has one second plane and one second inclined-plane that is not parallel to each other, wherein first inclined-plane makes the plane parallel of winning in second plane towards second inclined-plane, and first laser beam focuses in the optical record medium after by the first wedge shape optical sheet and the second wedge shape optical sheet again; Optical sheet locating module control, detect and the position of the relatively move first wedge shape optical sheet and the second wedge shape optical sheet, to change the optical sheet path of this first laser beam by the first wedge shape optical sheet and the second wedge shape optical sheet; Photodetector receives, detects second laser beam that is transmitted by spectroscope.
From the above, because of having two wedge shape optical sheets according to optical read head of the present invention and utilizing the optical sheet locating module to cooperate each recording layer thickness of optical record medium, the position of suitably adjusting the first wedge shape optical sheet and the second wedge shape optical sheet makes the light path of the laser beam process of winning be able to suitable correction, so that the aberration when alleviating first laser beam and focusing on optical record medium is to reach the effect that alleviates aberration and can read the multilayer data.
Description of drawings
Figure 1A is a synoptic diagram, shows that existing optical read head reads double-deck optical record medium, and it is first recording layer that reads multilayer optical recording medium;
Figure 1B is a synoptic diagram, shows that existing optical read head reads double-deck optical record medium, and it is second recording layer that reads multilayer optical recording medium;
Fig. 2 A is a synoptic diagram, shows the optical read head according to preferred embodiment of the present invention;
Fig. 2 B is a synoptic diagram, shows the optical read head according to preferred embodiment of the present invention, and it does not comprise plane mirror;
Fig. 3 A is a synoptic diagram, shows that the optical read head according to preferred embodiment of the present invention reads single layer optical recording medium;
Fig. 3 B is a synoptic diagram, shows first recording layer that reads multilayer optical recording medium according to the optical read head of preferred embodiment of the present invention;
Fig. 3 C is a synoptic diagram, shows second recording layer that reads multilayer optical recording medium according to the optical read head of preferred embodiment of the present invention;
Fig. 3 D is a synoptic diagram, shows the 3rd recording layer that reads multilayer optical recording medium according to the optical read head of preferred embodiment of the present invention;
Fig. 4 A is a synoptic diagram, shows the optical read head according to preferred embodiment of the present invention, and wherein first inclined-plane contacts second inclined-plane, and the direction that relatively moves of the first wedge shape optical sheet and the second wedge shape optical sheet is parallel to first plane;
Fig. 4 B is a synoptic diagram, shows the optical read head according to preferred embodiment of the present invention, and wherein first inclined-plane is parallel does not contact second inclined-plane, and the direction that relatively moves of the first wedge shape optical sheet and the second wedge shape optical sheet is parallel to first plane;
Fig. 4 C is a synoptic diagram, shows the optical read head according to preferred embodiment of the present invention, and wherein first inclined-plane contacts second inclined-plane, and the direction that relatively moves of the first wedge shape optical sheet and the second wedge shape optical sheet is parallel to first inclined-plane;
Fig. 4 D is a synoptic diagram, shows the optical read head according to preferred embodiment of the present invention, parallel second inclined-plane that do not contact, first inclined-plane wherein, and the direction that relatively moves of the first wedge shape optical sheet and the second wedge shape optical sheet is parallel to first inclined-plane.
Symbol description among the figure
11 laser beams
12 condenser lenses
13 optical sheets
14 optical sheet locating modules
15 optical record mediums
151 first recording layers
152 overlayers
153 second recording layers
154 substrates
155 protective seams
21 LASER Light Source
22 spectroscopes
23 collimation lenses
24 plane mirrors
25 condenser lenses
26 photodetectors
27 actuators
28 actuators
29 laser beams
31 first wedge shape optical sheets
311 first planes
312 first inclined-planes
32 second wedge shape optical sheets
321 second planes
322 second inclined-planes
33 optical sheet locating modules
4 optical record mediums
41 first recording layers
42 overlayers
43 second recording layers
44 substrates
45 protective seams
5 optical record mediums
51 recording layers
52 substrates
53 protective seams
The thickness of t optical record medium
t
51The thickness of recording layer
t
52The thickness of substrate
t
53The thickness of protective seam
6 optical record mediums
61 first recording layers
62 first overlayers
63 second recording layers
64 second overlayers
65 the 3rd recording layers
66 substrates
67 protective seams
t
61The thickness of first recording layer
t
62The first tectal thickness
t
63The thickness of second recording layer
t
64The second tectal thickness
t
65The thickness of the 3rd recording layer
t
66The thickness of substrate
t
67The thickness of protective seam
Embodiment
Hereinafter with reference to relevant drawings, the optical read head according to preferred embodiment of the present invention is described, wherein components identical will be illustrated with identical reference marks.
Shown in Fig. 2 A, comprise a LASER Light Source 21, a spectroscope 22, collimation lens 23, a plane mirror 24, a condenser lens 25, one first wedge shape optical sheet 31, one second wedge shape optical sheet 32, an optical sheet locating module 33 and a photodetector 26 according to the optical read head of preferred embodiment of the present invention.
Wherein, LASER Light Source 21 emissions one first laser beam, spectroscope 22 separates with first laser beam and by one second laser beam that an optical record medium 4 is passed back, the position that one actuator 27 moves collimation lens 23 makes collimation lens 23 collimate first laser beam, first laser beam that plane mirror 24 reflections are transmitted by collimation lens 23, the position of an actuator 28 mobile focusing lens 25 focuses in the optical record medium 4 laser beam of winning; In addition, the first wedge shape optical sheet 31 has one first plane 311 and one first inclined-plane 312 that is not parallel to each other, and the second wedge shape optical sheet 32 has one second plane 321 and one second inclined-plane 322 that is not parallel to each other, wherein first inclined-plane 312 makes the plane 311 of winning be parallel to second plane 321 towards second inclined-plane 322, and first laser beam focuses in the optical record medium 4 after by the first wedge shape optical sheet 31 and the second wedge shape optical sheet 32 again; Optical sheet locating module 33 control, detect and the position of the relatively move first wedge shape optical sheet 31 and the second wedge shape optical sheet 32, to change the optical sheet path of this first laser beam by the first wedge shape optical sheet 31 and the second wedge shape optical sheet 32; Photodetector 26 receives, detects second laser beam that is transmitted by spectroscope 22.
First laser beam passes through spectroscope 22, collimation lens 23, plane mirror 24, condenser lens 25, first plane 311, first inclined-plane 312, second inclined-plane 322 and second plane 321 in regular turn after LASER Light Source 21 emissions, and focuses in this optical record medium 4.On the other hand, second laser beam sets out from optical record medium 4, pass through second plane 321, second inclined-plane 322, first inclined-plane 312, first plane 311, condenser lens 25, plane mirror 24, collimation lens 23 and spectroscope 22 in regular turn, and be sent to photodetector 26.Moreover, if first laser beam is not to be that a Circular Polarisation laser beam (Circularly Polarized Laser) is a Linear Polarised Laser light beam (Linearly Polarized Laser), then must add a quarter wave plate at spectroscope 22 and 23 of collimation lenses, making the laser beam of winning is the Circular Polarisation laser beam by the Linear Polarised Laser Beam Transformation.
In addition, shown in Fig. 2 B, can not comprise plane mirror 24 according to the optical read head of preferred embodiment of the present invention, the element shown in other element and Fig. 2 A repeats, and does not repeat them here.
As shown in Figure 3A, an optical record medium 5 comprises a recording layer 51, a substrate 52 and a protective seam 53, and wherein the thickness of recording layer 51 is t
51, the thickness of substrate 52 is t
52, the thickness of protective seam 53 is t
53, the gross thickness of each layer is t.It is noted that, among optical record medium 5, on recording layer 51, can be formed with a reflection horizon, so that will be incident upon a laser beam 29 reflections of optical record medium 5, the thickness of right recording layer 51 is that atomic I is ignored with respect to other rete, does not carry (following icon and embodiment explanation are also together) so omit in Fig. 3 A.
Shown in Fig. 3 B, 3C and 3D; it comprises one first recording layer 61, one first overlayer 62, one second recording layer 63, one second overlayer 64, one the 3rd recording layer 65, a substrate 66 and a protective seam 67 one optical record medium 6, and wherein the thickness of each layer is docile and obedient preface and is respectively t
61, t
62, t
63, t
64, t
65, t
66And t
67, the gross thickness of each layer also is t.
Shown in Fig. 3 B, laser beam 29 is in regular turn by focusing on first recording layer 61 of optical record medium 6 behind the condenser lens 25, this moment is in order to alleviate the influence of aberration, condenser lens 25 is done the correction of aberration optimization at the thickness of first recording layer 61, so do not need to alleviate aberration with the first wedge shape optical sheet 31 and the second wedge shape optical sheet 32 again.
Shown in Fig. 3 C, laser beam 29 is in regular turn by focusing on second recording layer 63 of optical record medium 6 behind condenser lens 25, the first wedge shape optical sheet 31 and the second wedge shape optical sheet 32, this moment, the mobile first wedge shape optical sheet 31 of optical sheet locating module 33 controls and the second wedge shape optical sheet 32 were to the appropriate location, make laser beam 11 through the optical sheet path of the first wedge shape optical sheet 31 and the second wedge shape optical sheet 32 suc as formula 1, the aberration when focusing on second recording layer 63 to alleviate laser beam 29.
Formula 1 optical sheet path=(t
52-t
66-t
65-t
64) * n
52÷ n
n
52: the refraction coefficient of substrate 52
N: the refraction coefficient of the first wedge shape optical sheet 31 and the second wedge shape optical sheet 32.
Wherein, (t
52-t
66-t
65-t
64) promptly represent the distance of first recording layer 61 and second recording layer 63.
Shown in Fig. 3 D, laser beam 29 is in regular turn by focusing on the 3rd recording layer 65 of optical record medium 6 behind condenser lens 25, the first wedge shape optical sheet 31 and the second wedge shape optical sheet 32, this moment, the mobile first wedge shape optical sheet 31 of optical sheet locating module 33 controls and the second wedge shape optical sheet 32 were to the appropriate location, make laser beam 29 through the optical sheet path of the first wedge shape optical sheet 31 and the second wedge shape optical sheet 32 suc as formula 2, the aberration when focusing on the 3rd recording layer 65 to alleviate laser beam 29.
Formula 2 optical sheet path=(t
52-t
66) * n
52÷ n
n
52: the refraction coefficient of substrate 52
N: the refraction coefficient of the first wedge shape optical sheet 31 and the second wedge shape optical sheet 32.
Wherein, (t
52-t
66) promptly represent the distance of first recording layer 61 and the 3rd recording layer 65.
Shown in Fig. 4 A, the optical sheet locating module 33 control first wedge shape optical sheet 31 and the second wedge shape optical sheets 32, wherein first inclined-plane 312 can contact second inclined-plane 322.In addition, the direction that relatively moves of the first wedge shape optical sheet 31 and the second wedge shape optical sheet 32 can be parallel to first plane 311.Moreover when the first wedge shape optical sheet 31 and the second wedge shape optical sheet 32 relatively moved, its mode of motion can be that the fixing and second wedge shape optical sheet 32 of the first wedge shape optical sheet 31 moves; Maybe can be that the first wedge shape optical sheet 31 moves and the second wedge shape optical sheet 32 is fixed; Maybe can be that the first wedge shape optical sheet 31 moves and the second wedge shape optical sheet 32 also moves.
Shown in Fig. 4 B, the optical sheet locating module 33 control first wedge shape optical sheet 31 and the second wedge shape optical sheets 32, with different shown in Fig. 4 A be that first inclined-plane 312 does not contact with second inclined-plane, 322 keeping parallelisms.
Shown in Fig. 4 C, the optical sheet locating module 33 control first wedge shape optical sheet 31 and the second wedge shape optical sheets 32, with different shown in Fig. 4 A be that the direction that relatively moves of the first wedge shape optical sheet 31 and the second wedge shape optical sheet 32 can be parallel to first inclined-plane 312.
Shown in Fig. 4 D, the optical sheet locating module 33 control first wedge shape optical sheet 31 and the second wedge shape optical sheets 32, with different shown in Fig. 4 C be that first inclined-plane 312 can not contact second inclined-plane 322 and mutual keeping parallelisms.
In sum, because of having the optical sheet locating module according to optical read head of the present invention, it cooperates each recording layer thickness of optical record medium, the position of suitably adjusting the first wedge shape optical sheet and the second wedge shape optical sheet makes the laser beam of winning be able to suitable correction through the light path of the first wedge shape optical sheet and the second wedge shape optical sheet, and alleviate aberration after first laser beam focuses on optical record medium, to reach the effect that reduces aberration and can read the multilayer data.
The above only is an illustrative, but not is restricted.Anyly do not break away from spirit of the present invention and category, and, all should be contained in the scope of claims its equivalent modifications of carrying out or change.
Claims (14)
1, an optical read head is characterized in that, comprises:
One LASER Light Source, it launches one first laser beam;
One spectroscope, it separates with this first laser beam and by one second laser beam that an optical record medium is passed back;
One collimation lens, it collimates this first laser beam;
One condenser lens, it focuses in this optical record medium this first laser beam;
One first wedge shape optical sheet, it has one first plane and one first inclined-plane that is not parallel to each other;
One second wedge shape optical sheet, it has one second plane and one second inclined-plane that is not parallel to each other, wherein this first inclined-plane is towards this second inclined-plane, make this first plane parallel in this second plane, and this first laser beam focus in this optical record medium after by this first wedge shape optical sheet and this second wedge shape optical sheet again;
One optical sheet locating module, the position of its control, detect and relatively move this first wedge shape optical sheet and this second wedge shape optical sheet is to change the optical sheet path of this first laser beam by this first wedge shape optical sheet and this second wedge shape optical sheet; And
One photodetector, it receives, detects this second laser beam that is transmitted by this spectroscope.
2, optical read head as claimed in claim 1, wherein, this first laser beam passes through this spectroscope, this collimation lens, this condenser lens, this first plane, this first inclined-plane, this second inclined-plane and this second plane in regular turn, and focuses in this optical record medium.
3, optical read head as claimed in claim 1, wherein, this second laser beam sets out from this optical record medium, pass through this second plane, this second inclined-plane, this first inclined-plane, this first plane, this condenser lens, this collimation lens and this spectroscope in regular turn, and be sent to this photodetector.
4, optical read head as claimed in claim 1 wherein, more comprises a plane mirror, this first laser beam that its reflection is transmitted by this collimation lens.
5, optical read head as claimed in claim 4, wherein, this first laser beam is in regular turn by this spectroscope, this collimation lens, this plane mirror, this condenser lens, this first plane, this first inclined-plane, this second inclined-plane and this second plane, and focus in this optical record medium, and this second laser beam sets out from this optical record medium, pass through this second plane, this second inclined-plane, this first inclined-plane, this first plane, this condenser lens, this plane mirror, this collimation lens and this spectroscope in regular turn, and be sent to this photodetector.
6, optical read head as claimed in claim 1 wherein, more comprises: a quarter wave plate, it will pass this spectroscopical this first laser beam and be converted to a Circular Polarisation laser beam by a Linear Polarised Laser.
7, optical read head as claimed in claim 1, wherein, this optical sheet locating module is controlled the relative motion of this first wedge shape optical sheet and this second wedge shape optical sheet, makes this first laser beam change by an optical sheet path of this first wedge shape optical sheet and this second wedge shape optical sheet.
8, optical read head as claimed in claim 7, wherein, this optical sheet path is the difference of distance of the reading face of another recording layer of the distance of reading face of a recording layer of this optical record medium and this optical record medium and this optical record medium and this optical record medium, multiply by the substrate refraction coefficient of this optical record medium, and divided by the refraction coefficient of this first wedge shape optical sheet and this second wedge shape optical sheet.
9, optical read head as claimed in claim 1, wherein, this first wedge shape optical sheet and the contact of this second wedge shape optical sheet or parallelly do not contact.
10, optical read head as claimed in claim 1, wherein, the direction that relatively moves of this first wedge shape optical sheet and this second wedge shape optical sheet is parallel to this first inclined-plane or is parallel to this first plane.
11, optical read head as claimed in claim 1, wherein, when relatively moving this first wedge shape optical sheet and this second wedge shape optical sheet, this first wedge shape optical sheet is fixed and this second wedge shape optical sheet moves.
12, optical read head as claimed in claim 1, wherein, when relatively moving this first wedge shape optical sheet and this second wedge shape optical sheet, this first wedge shape optical sheet moves and this second wedge shape optical sheet is fixed or move.
13, optical read head as claimed in claim 1, wherein, this optical record medium is discs or is the magneto-optic sheet.
14, optical read head as claimed in claim 1, wherein, this optical record medium comprises several recording layers.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2004100683584A CN1332386C (en) | 2004-08-31 | 2004-08-31 | Optical reading head |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2004100683584A CN1332386C (en) | 2004-08-31 | 2004-08-31 | Optical reading head |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1744215A CN1744215A (en) | 2006-03-08 |
| CN1332386C true CN1332386C (en) | 2007-08-15 |
Family
ID=36139550
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2004100683584A Expired - Fee Related CN1332386C (en) | 2004-08-31 | 2004-08-31 | Optical reading head |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1332386C (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5373492A (en) * | 1992-02-28 | 1994-12-13 | Canon Kabushiki Kaisha | Optical information recording/reproducing apparatus |
| US5515353A (en) * | 1993-03-05 | 1996-05-07 | Olympus Optical Co., Ltd. | Optical head with forward and return light beam propagating along a common path |
| CN1287354A (en) * | 1999-09-03 | 2001-03-14 | Lg电子株式会社 | Optical pickup using for preventing astigmatic difference |
-
2004
- 2004-08-31 CN CNB2004100683584A patent/CN1332386C/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5373492A (en) * | 1992-02-28 | 1994-12-13 | Canon Kabushiki Kaisha | Optical information recording/reproducing apparatus |
| US5515353A (en) * | 1993-03-05 | 1996-05-07 | Olympus Optical Co., Ltd. | Optical head with forward and return light beam propagating along a common path |
| CN1287354A (en) * | 1999-09-03 | 2001-03-14 | Lg电子株式会社 | Optical pickup using for preventing astigmatic difference |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1744215A (en) | 2006-03-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US20070171557A1 (en) | Optical head, optical information storage apparatus, and their fabrication method | |
| US7170832B2 (en) | Optical scanning device | |
| KR20030088427A (en) | Beamshaper for optical head | |
| CN101802913B (en) | Apparatus and method for recording/reproducing holographic data and holographic data storage medium | |
| CN101828226A (en) | Extraction optical system and optical head device including same | |
| JP4284209B2 (en) | Reproducing apparatus, recording / reproducing apparatus, and reproducing method | |
| US8325581B2 (en) | Optical head and optical disc device | |
| EP0911818A1 (en) | Compact dual wavelength optical pickup head | |
| CN1332386C (en) | Optical reading head | |
| CN102934166A (en) | Optical pickup, inclination angle detection method, optical information device and information processing device | |
| CN101964197A (en) | Optical picking-up device | |
| CN100380480C (en) | Optical pick-up apparatus | |
| CN101079285B (en) | Optical pickup apparatus | |
| TW492001B (en) | Double focused optical read/write head | |
| US8427924B2 (en) | Optical pickup apparatus | |
| US8477573B2 (en) | Optical pickup head | |
| JPS62197933A (en) | Optical pickup | |
| US20040190425A1 (en) | Optical pickup device | |
| US20070223329A1 (en) | Apparatus And Method For Generating A Scanning Beam In An Optical Pickup Head, Miniature Optical Pickup Head And Optical Storage System Incorporating A Miniature Pickup Head | |
| CN101197153A (en) | Optical pickup device and optical disc apparatus | |
| JP3003160B2 (en) | Composite beam splitter element and optical head for magneto-optical disk using the same | |
| JPS62200543A (en) | Optical pickup | |
| TW448442B (en) | Diffractive stack pickup head for optical disk drives and method to fabricate the pickup head | |
| US20060193215A1 (en) | Optical head and optical disk device | |
| JPS62162238A (en) | Optical recorder |
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: 20070815 Termination date: 20090930 |