Patent US4633458A successfully refreshed from Google Patents.
US4633458A
Expired / Lapsed
US
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Disc-shaped, optically-readable information carrier having a protective edge and/or center part
Assignee: Polygram GmbH
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Filing: 1984-03-30
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Granted: 1986-12-30
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Expires: 2004-03-30
Abstract
Abstract High storage density, optically-readable information carriers not only require a read-out side free of contaminants or dust for a faultless reading, but must also be protected against unintentional scratching when being handled on this side. For protection against scratches that usually occur due to dislocation of a disc deposited on its support, concentric elevations are provided that are structured under given conditions by clearances on the read-out side in the edge region and in the central region of the disc outside of the information structure which fills a concentric annular surface. The disc is able to slide on the elevations when deposited on the support without the annular surface, provided with the microstructure, coming into contact with the support.
Inventors
- 👤 Volkmar Tiefensee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 12:49
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/26; G11B7/24097
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
116 words
In a disc-shaped, high storage density optically-readable information carrier of the type having an access of rotation, and in which an information microstructure is carried on a surface of the carrier in an annular first region concentric of and spaced from the axis of rotation by a second region, in which the carrier has a read-out surface for receiving a light beam, and in which a protective structure is carried by and projects from the read-out surface in a third region located about the first region, the improvement comprising: a further protective structure carried on and projecting from the read-out surface in the second region, said further protective structure comprising a plurality of angularly-spaced radially-extending members.
Claim 2
Dependent Claim
116 words
In a disc-shaped, high storage density optically-readable information carrier of the type having an access of rotation, and in which an information microstructure is carried on a surface of the carrier in an annular first region concentric of and spaced from the axis of rotation by a second region, in which the carrier has a read-out surface for receiving a light beam, and in which a protective structure is carried by and projects from the read-out surface in a third region located about the first region, the improvement comprising: a further protective structure carried on and projecting from the read-out surface in the second region, said further protective structure comprising a plurality of angularly-spaced radially-extending members.
Claim 3
Dependent Claim
19 words
The improved information carrier of claim 1, wherein: said angularly-spaced radially extending members are spaced in a regular pattern.
Claim 4
Dependent Claim
18 words
The improved information carrier of claim 1, wherein: each of said angularly-spaced radially-extending members is a tear-shaped projection.
Claim 5
Dependent Claim
18 words
The improved information carrier of claim 1, wherein: the first-mentioned protective structure comprises a plurality of spaced projections.
Claim 6
Dependent Claim
18 words
The improved information carrier of claim 1, wherein: the first-mentioned protective structure comprises a plurality of equally-spaced projections.
Claim 7
Dependent Claim
19 words
The improved information carrier of claim 1, wherein: the first-mentioned protective structure comprises a plurality of spaced tear-shaped projections.
References Cited (Backward Citations)
US4074282A
Cited
GB2004404A
Cited
US4353767A
Cited
DE3127993A1
Cited
US4462036A
Cited
US4536869A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-12-29 | 1990-06-30 | 1990-12-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-12-29 | 1994-06-30 | 1994-12-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-12-29 | 1998-06-30 | 1998-12-30 | $7700.00 | Window Closed / Lapsed |