US4899168A
Expired / Lapsed
US
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Optical recording medium
Assignee: Canon Inc
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Filing: 1988-08-25
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Granted: 1990-02-06
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Expires: 2008-08-25
Abstract
Abstract An optical recording medium made up of a substrate and an electromagnetic radiation sensitive layer consisting essentially of a sulfur compound as a matrix and a substance (such as, for example, Te, Pb, Au, Sn, As, Bi, In, C) which is subjected to heat action from absorption of electromagnetic radiation and brings about optical changes by such heat action.
Inventors
- 👤 Yoichi Osato
- 👤 Ichiro Saito
- 👤 Yoshio Takasu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 14:16
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/241; G11B7/242; G11B7/243; G11B2007/24302; G11B2007/24306; G11B2007/24308; G11B2007/24312; G11B2007/24314; G11B2007/24316; G11B2007/24318; G11B2007/24324; G11B7/252; G11B7/253; G11B7/2531; G11B7/2533; Y; Y10; Y10S; Y10S430/00; Y10S430/146
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
89 words
A method for preparing a laser beam-readable optical recording medium comprising: providing a medium including a substrate having thereon a thin film containing a sulfur compound and a substance capable of undergoing a change in reflectivity through the absorption of electromagnetic radiation; and irradiating said medium with an electromagnetic radiation beam which is sufficient to form on said thin film, pitted sections having higher reflectivity than unpitted sections of said medium surrounding said pitted sections but is insufficient to cause depressions or to create holes in said thin film.
Claim 2
Independent Claim
89 words
A method for preparing a laser beam-readable optical recording medium comprising: providing a medium including a substrate having thereon a thin film containing a sulfur compound and a substance capable of undergoing a change in reflectivity through the absorption of electromagnetic radiation; and irradiating said medium with an electromagnetic radiation beam which is sufficient to form on said thin film, pitted sections having higher reflectivity than unpitted sections of said medium surrounding said pitted sections but is insufficient to cause depressions or to create holes in said thin film.
Claim 3
Dependent Claim
27 words
The method according to claim 1, wherein said thin film contains said substance capable of undergoing a change in reflectivity in a matrix of said sulfur compound.
Claim 4
Dependent Claim
36 words
The method according to claim 1, wherein said thin film is a coated film comprising a substance capable of undergoing a change in reflectivity through absorption of electromagnetic radiation contained in a matrix of sulfur compound.
Claim 5
Dependent Claim
33 words
The method according to claim 1, wherein the substance capable of undergoing a change in reflectivity through absorption of electromagnetic radiation is contained in an amount ranging from 20 to 70 mole percent.
Claim 6
Dependent Claim
71 words
The method according to claim 1, wherein said sulfur compound is at least one kind selected from the group consisting of tin (II) sulfide, antimony (III) sulfide, germanium (II) sulfide, arsenic sulfide, tungsten (IV) sulfide, aluminum sulfide, indium (III) sulfide, silver (I) sulfide, chromium (II) sulfide, cobalt (II) sulfide, tantalum (IV) sulfide, copper (I) sulfide, lead (II) sulfide, bismuth (III) sulfide, manganese (II) sulfide, molybdenum (IV) sulfide, and carbon sulfide polymers.
Claim 7
Dependent Claim
19 words
The method according to claim 5, wherein said sulfur compound is a metal sulfide represented by SnS x1 (0<x1≦1).
Claim 8
Dependent Claim
19 words
The method according to claim 5, wherein said sulfur compound is a metal sulfide represented by InS 2 (0<x2≦2/3).
Claim 9
Dependent Claim
35 words
The method according to claim 1, wherein said substance capable of undergoing a change in reflectivity through the absorption of electromagnetic radiation is one which brings about the change in reflectivity by action of heat.
Claim 10
Dependent Claim
50 words
The method according to claim 8, wherein said substance capable of undergoing a change in reflectivity through the absorption of electromagnetic radiation is at least one kind selected from the group consisting of tellurium (Te), lead (Pb), gold (Au), tin (Sn), arsenic (As), bismuth (Bi), indium (In), and carbon (C).
Claim 11
Dependent Claim
36 words
The method according to claim 1, further comprising providing a protective film layer on said film containing said sulfur compound and said substance capable of undergoing a change in reflectivity through the absorption of electromagnetic radiation;
Claim 12
Dependent Claim
37 words
The method according to claim 1, further comprising providing a reflection preventive film on said thin film containing said sulfur compound and said substance capable of undergoing a change in reflectivity through the absorption of electromagnetic radiation.
Claim 13
Dependent Claim
38 words
The method according to claim 1, further comprising interposing a reflective layer between said substrate and said thin film containing said sulfur compound and said substance capable of undergoing change in reflectivity through the absorption of electromagnetic radiation.
Claim 14
Dependent Claim
16 words
The method according to claim 1, wherein said substrate is made of polyester or polymethyl methacrylate.
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) | 1993-02-05 | 1993-08-07 | 1994-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-02-05 | 1997-08-07 | 1998-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-02-05 | 2001-08-07 | 2002-02-06 | $7700.00 | Window Closed / Lapsed |