EP0054438A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Optical disk having an index mark
Assignee: Panasonic Holdings Corp
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Filing: 1981-12-16
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Granted: —
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Expires: 2001-12-16
Abstract
Abstract An optical disk (1) for optically recording and reproducing information thereon and therefrom, comprising: (a) a substrate; (b) a recording layer deposited on at least one side of said substrate; and (c) a rotation index mark (9) indicative of a starting point of the rotation of said disk, said index mark being constructed of a groove-like phase structure within said substrate and said recording layer.
Inventors
- 👤 Isao Satoh
- 👤 Tomio Yoshida
- 👤 Shunji Harigae
- 👤 Kenji Koishi
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-25 11:58
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/2407; G11B7/24085; G11B17/00; G11B17/005; G11B19/00; G11B19/20; G11B19/28; G11B23/00; G11B23/38; G11B23/42; G11B27/00; G11B27/10; G11B27/102; G11B27/105; G11B27/19; G11B27/24; G11B27/28; G11B27/30; G11B27/3027; G11B7/007; G11B7/00745; G11B2220/00; G11B2220/20; G11B2220/25; G11B2220/2537; G11B2220/2587
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
63 words
An optical disk for optically recording and reproducing information thereon and therefrom, comprising: (a) a substrate; (b) a recording layer deposited on at least one side of said substrate; and (c) a rotation index mark indicative of a starting point of the rotation of said disk, said index mark being constructed of a groove-like phase structure within said substrate and said recording layer.
Claim 2
Dependent Claim
63 words
An optical disk for optically recording and reproducing information thereon and therefrom, comprising: (a) a substrate; (b) a recording layer deposited on at least one side of said substrate; and (c) a rotation index mark indicative of a starting point of the rotation of said disk, said index mark being constructed of a groove-like phase structure within said substrate and said recording layer.
Claim 3
Dependent Claim
46 words
An optical disk as claimed in Claim 1, wherein said rotation index mark comprises a plurality of groove-like portions aligned radially, each of said groove-like portions being arcuate so that said groove-like phase structure has a given angle with respect to the center of said disk.
Claim 4
Dependent Claim
32 words
An optical disk as claimed in Claim 2, wherein each of the arcuate portions comprises a repetitive pattern of concave-convexo pits aligned in a direction parallel to the circumferece of said disk.
Claim 5
Dependent Claim
51 words
An optical disk as claimed in Claim 1/ further comprising coaxial or spiral groove-like guide tracks for recording main information therein, each of said guide tracks having a portion carrying its track address, the track address portions of said guide tracks being radially aligned to form a sectoral track address region.
Claim 6
Dependent Claim
35 words
An otical disk as claimed in Claim 4, wherein said rotation index mark is positioned so as to make a predetermined angle with said track address region with respect to the center of said disk.
Claim 7
Dependent Claim
52 words
An optical disk as claimed in Claim 1 L further comprising a plurality of sector index marks indicative of sectors with which information tracks are divided into a plurality of sectoral regions, each of said sector index marks being constructed of a groove-like phase structure within said substrate and said recording layer.
Claim 8
Dependent Claim
70 words
An optical disk as claimed in Claiml5, further comprising a plurality of sector index marks indicative of sectors with which the information tracks are divided into a plurality of sectoral regions; and an address index mark indicative of the position of said track address region, each of said sector index marks and said address index mark being constructed of a groove-like phase structure within said substrate and said recording layer.
Claim 9
Dependent Claim
57 words
An optical disk as claimed in Claim 6 or 7, wherein at least one of said rotation index mark and said sector index marks comprises a plurality of groove-like portions aligned radially, each of said groove-like portions being arcuate so that said groove-like phase structure has a given angle with respect to the center of said disk.
Claim 10
Dependent Claim
37 words
An optical disk as claimed in Claim 8, wherein each of the arcuate portions of said sector index mark comprises a repetitive pattern of concave-convexo pits aligned in a direction parallel to the circumferece of said disk.
Claim 11
Dependent Claim
26 words
An optical disk as claimed in any preceding Claim wherein said rotation index mark is provided inside information tracks in which main information will be recorded.
Claim 12
Dependent Claim
38 words
An optical disk as claimed in Claim 6, 7, 8 or 9, wherein at least one of said rotation index mark and said sector index marks is provided inside information tracks in which main information will be recorded.
Claim 13
Dependent Claim
38 words
An optical disk as claimed in Claim 6,7, 8 or 9 wherein said rotation index mark and said sector index marks are formed on a single track positioned inside information tracks in which main information will be recorded.
Claim 14
Dependent Claim
33 words
An optical disk as claimed in Claim 7, wherein said rotation index mark, said sector index marks and said address index mark are formed on a single track positioned inside said guide track.
Claim 15
Dependent Claim
53 words
An optical disk as claimed in any preceding Claim further comprising another rotation index mark on the other side of said disk, said another rotation index mark having different structure from that of the first-mentioned rotation index mark so that the front and back of said disk can be distinguished from each other.
References Cited (Backward Citations)
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