US5477527A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High density optical disc and optical disc player
Assignee: Sanyo Electric Co Ltd
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Filing: 1994-04-14
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Granted: 1995-12-19
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Expires: 2014-04-14
Abstract
Abstract A high density optical disc having a track pitch of 0.85 μm, a shortest pit length of 0.49 μm, a pit depth of 100 nm, and a pit width of 0.35 μm is rotated at a linear velocity of 2.4-2.8 m/s such that the same is optically reproduced by a laser beam having a wavelength of 635 nm which is converged to a spot size of 0.9 μm by an objective lens having a numerical aperture of 0.6. Accordingly, data is read from the optical disc at a transfer rate of 5.6 Mbps.
Inventors
- 👤 Yoichi Tsuchiya
- 👤 Hitoshi Terasaki
- 👤 Shuichi Ichiura
- 👤 Toshio Ito
- 👤 Yasuyuki Kano
- 👤 Yoshimoto Yamaguchi
- 👤 Seizo Kato
- 👤 Osamu Ota
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 04:28
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B19/00; G11B19/20; G11B19/26; G11B7/002; G11B7/0037; G11B7/004; G11B7/005; G11B7/08; G11B7/09; G11B7/0938; G11B7/12; G11B7/125; G11B7/127; G11B7/135; G11B7/1372; G11B7/1374; G11B7/2407; G11B7/24073; G11B7/24079; G11B7/24085
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
24 words
An optical disc having a track pitch of 0.7-0.85 μm, a pit width of 0.20-0.35 μm, and a shortest pit length of 0.42-0.49 μm.
Claim 2
Dependent Claim
24 words
An optical disc having a track pitch of 0.7-0.85 μm, a pit width of 0.20-0.35 μm, and a shortest pit length of 0.42-0.49 μm.
Claim 3
Dependent Claim
14 words
An optical disc according to claim 1, wherein said track pitch is 0.85 μm.
Claim 4
Dependent Claim
15 words
An optical disc according to claim 1, wherein said shortest pit length is 0.49 μm.
Claim 5
Dependent Claim
22 words
An optical disc according to claim 1, wherein said track pitch is 0.85 μm, and said shortest pit length is 0.49 μm.
Claim 6
Dependent Claim
82 words
An optical disc player for reproducing information signals from an optical disc having a track pitch of 0.7-0.85 μm, a pit width of 0.20-0.35 μm, and a shortest pit length of 0.42-0.49 μm, comprising: a semiconductor laser having a wavelength of 590-670 nm; irradiating means for irradiating a beam from said semiconductor laser onto said optical disc with a spot size of 0.85-0.95 μm; and a photo-receiving means for receiving a reflected beam from said optical disc and outputting a reproduced signal.
Claim 7
Dependent Claim
82 words
An optical disc player for reproducing information signals from an optical disc having a track pitch of 0.7-0.85 μm, a pit width of 0.20-0.35 μm, and a shortest pit length of 0.42-0.49 μm, comprising: a semiconductor laser having a wavelength of 590-670 nm; irradiating means for irradiating a beam from said semiconductor laser onto said optical disc with a spot size of 0.85-0.95 μm; and a photo-receiving means for receiving a reflected beam from said optical disc and outputting a reproduced signal.
Claim 8
Dependent Claim
24 words
A disc player according to claim 5, wherein said irradiating means includes means for irradiating said beam with a spot size of 0.90 μm.
Claim 9
Dependent Claim
19 words
A disc player according to claim 5, said irradiating means includes a beam condensing means for condensing said beam.
Claim 10
Dependent Claim
23 words
A disc player according to claim 6, wherein said beam condensing means includes an objective lens having a numerical aperture of approximately 0.6.
Claim 11
Dependent Claim
15 words
A disc player according to claim 5, wherein said irradiating means includes beam condensing means.
Claim 12
Dependent Claim
23 words
A disc player according to claim 5, further comprising motor means for rotating said optical disc at a linear velocity of 2.4-2.8 m/s.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-12-18 | 1999-06-19 | 1999-12-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-12-18 | 2003-06-19 | 2003-12-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-12-18 | 2007-06-19 | 2007-12-19 | $7700.00 | Window Closed / Lapsed |