US4847478A
Expired / Lapsed
US
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Optical pick-up device
Assignee: Pioneer Corp
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Filing: 1988-05-19
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Granted: 1989-07-11
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Expires: 2008-05-19
Abstract
Abstract An optical pick-up device includes a light source for irradiating a recording medium to record and/or reproduce information, an objective lens for condensing beams of the light which are reflected or transmitted by the recording medium, an optical member such as a parallel plane plate or a diffraction grating for imposing a diffraction pattern upon the condensed light, and a photo detector for detecting the presence and amount of the patterned light in each of a plurality of regions. The regions on the photo detector correspond to those created by lines curved in accordance with a comatic aberration of the optical member. In particular, the curved lines correspond to the projection of first and second rectilinear lines through the objective lens and the optical member onto the photo detector. The first rectilinear line is parallel to a track on the recording medium, and the second rectilinear is perpendicular to the track.
Inventors
- 👤 Satoshi Sugiura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-10 02:34
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/12; G11B7/135; G11B7/1365; G11B7/08; G11B7/09; G11B7/0908; G11B7/0909; G11B7/094; G11B7/13; G11B7/133; G11B7/1353
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
106 words
An optical pick-up device comprising: means for irradiating a recording medium with light to perform at least one of recording and reproducing information; means for condensing the light which is at least one of reflected and transmitted by said recording medium; an optical member for receiving the condensed light, and for imposing a detectable pattern on the light, said light from said optical member having a comatic aberration; and photosensitive means, divided into a plurality of regions, for receiving the light from said optical member, and for detecting the light in regions, said regions being determined based on lines curved in accordance with the comatic aberration.
Claim 2
Dependent Claim
106 words
An optical pick-up device comprising: means for irradiating a recording medium with light to perform at least one of recording and reproducing information; means for condensing the light which is at least one of reflected and transmitted by said recording medium; an optical member for receiving the condensed light, and for imposing a detectable pattern on the light, said light from said optical member having a comatic aberration; and photosensitive means, divided into a plurality of regions, for receiving the light from said optical member, and for detecting the light in regions, said regions being determined based on lines curved in accordance with the comatic aberration.
Claim 3
Dependent Claim
42 words
The optical pick-up device according to claim 1, further comprising means for performing focussing and tracking of the light irradiating the recording medium produced by said irradiating means based on relative amounts of light detected in said regions by said photosensitive means.
Claim 4
Dependent Claim
16 words
The optical pick-up device according to claim 1, wherein said photosensitive means comprises a photo detector.
Claim 5
Dependent Claim
17 words
The optical pick-up device according to claim 1, wherein said optical member comprises a parallel plane plate.
Claim 6
Dependent Claim
17 words
The optical pick-up device according to claim 1, wherein said means for condensing comprises an objective lens.
Claim 7
Dependent Claim
17 words
The optical pick-up device according to claim 1, wherein said photosensitive means is divided into four regions.
Claim 8
Dependent Claim
41 words
The optical pick-up device according to claim 1, wherein said lines comprise first and second curved lines corresponding to the projection of first and second rectilinear lines through said means for condensing and said optical member onto said photo sensitive means.
Claim 9
Dependent Claim
35 words
The optical pick-up device according to claim 7, wherein the recording medium has at least one track formed thereon, and said first and second rectilinear lines are parallel to and perpendicular to the track, respectively.
Claim 10
Dependent Claim
134 words
An optical pick-up device comprising: means for irradiating a recording medium with light to perform at least one of recording and reproducing information; means for condensing the light which is at least one of reflected and transmitted by said recording medium; an optical member for receiving the condensed light, and for imposing a detectable pattern on the light, said light from said optical member having a comatic aberration; and photosensitive means, divided into a plurality of regions, for receiving the light from said optical member, and for detecting the light in the regions, said regions being determined based on lines curved in accordance with lines parallel and/or vertical relative to a track on said recording medium, said parallel and/or vertical lines being passed through said optical member to be projected on said photosensitive means.
Claim 11
Dependent Claim
134 words
An optical pick-up device comprising: means for irradiating a recording medium with light to perform at least one of recording and reproducing information; means for condensing the light which is at least one of reflected and transmitted by said recording medium; an optical member for receiving the condensed light, and for imposing a detectable pattern on the light, said light from said optical member having a comatic aberration; and photosensitive means, divided into a plurality of regions, for receiving the light from said optical member, and for detecting the light in the regions, said regions being determined based on lines curved in accordance with lines parallel and/or vertical relative to a track on said recording medium, said parallel and/or vertical lines being passed through said optical member to be projected on said photosensitive means.
References Cited (Backward Citations)
US4625303A
Cited
US4742218A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-07-10 | 1993-01-09 | 1993-07-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-07-10 | 1997-01-09 | 1997-07-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-07-10 | 2001-01-09 | 2001-07-11 | $7700.00 | Window Closed / Lapsed |