US5220556A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical disk with identification phase-encoded area
Assignee: Ricoh Co Ltd
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Filing: 1990-10-25
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Granted: 1993-06-15
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Expires: 2010-10-25
Abstract
Abstract An optical disk having a recording area and an identification phase-encoded part (PEP) area with pits from which system data on the optical disk is reproduced without tracking, in which when the track pitch for the PEP area and the track pitch for the recording area are the same, the relationship between the track pitch P in the PEP area and the width W of the pits measured at a height in the pits of half the pit depth D is set in the range of 0.4P≦W≦0.6P; and when the track pitch for the PEP area and the track pitch for the recording area are different, the relationship between the track pitch P in the PEP area and the width W of the pits measured at a height in the pit of half the pit depth D is set in the range of P≦2.5W.
Inventors
- 👤 Akihiko Shimizu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 21:16
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/002; G11B7/0037; G11B7/2407; G11B7/24085; G11B7/08; G11B7/09; G11B7/095
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
92 words
An optical disk comprising: a recording area and an identification phase-encoded area; said recording area and phase-encoded area each including information tracks with the same track pitch P formed in said recording area and said phase-encoded area; said information tracks of said phase-encoded area being formed with identification pits from which system data on said optical disk is reproduced, each of said identification pits having a width W which is measured at a height, in the pit, of half the depth of the pit; said width is set in the range: 0.4P≦W≦0.6P.
Claim 2
Dependent Claim
92 words
An optical disk comprising: a recording area and an identification phase-encoded area; said recording area and phase-encoded area each including information tracks with the same track pitch P formed in said recording area and said phase-encoded area; said information tracks of said phase-encoded area being formed with identification pits from which system data on said optical disk is reproduced, each of said identification pits having a width W which is measured at a height, in the pit, of half the depth of the pit; said width is set in the range: 0.4P≦W≦0.6P.
Claim 3
Dependent Claim
99 words
An optical disk comprising: a recording area and an identification phase-encoded area; said recording area and phase-encoded area each including information tracks with the track pitch R formed in said recording area being different from the track pitch P formed in said phase-encoded area; said information tracks of said phase-encoded area being formed with identification pits from which system data on said optical disk is reproduced, each of said identification pits having a width W which is measured at a height, in the pit, of half the depth of the pit; said width being set in the range: P≦2.5W.
Claim 4
Dependent Claim
99 words
An optical disk comprising: a recording area and an identification phase-encoded area; said recording area and phase-encoded area each including information tracks with the track pitch R formed in said recording area being different from the track pitch P formed in said phase-encoded area; said information tracks of said phase-encoded area being formed with identification pits from which system data on said optical disk is reproduced, each of said identification pits having a width W which is measured at a height, in the pit, of half the depth of the pit; said width being set in the range: P≦2.5W.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-06-14 | 1996-12-14 | 1997-06-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-06-14 | 2000-12-14 | 2001-06-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-06-14 | 2004-12-14 | 2005-06-15 | $7700.00 | Window Closed / Lapsed |