Patent US1975417A successfully refreshed from Google Patents.
EP0353391A2
Expired / Lapsed
EP
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Optical information recording medium
Assignee: Taiyo Yuden Co Ltd
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Filing: 1989-04-17
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Granted: —
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Expires: 2009-04-17
Abstract
Abstract An optical information recording medium of the type wherein recorded data are reproduced by scanning them with a laser beam, which comprises a ROM region (A) where optically readable pits are already formed and an information recordable region (B) where optically readable pits can be formed by irradiation with a writing laser beam, wherein the information recordable region comprises a light transmitting substrate (1) having a deformable surface, a light absorptive layer (2) overlaying the deformable surface, to absorb the writing laser beam, and a light reflective layer (3) overlaying the light absorptive layer, said deformable surface being deformable by energy generated upon absorption of the writing laser beam by the light absorptive layer, to form optically readable pits.
Inventors
- 👤 Emiko Hamada
- 👤 Yuji Arai
- 👤 Yuaki Shin
- 👤 Takashi Ishiguro
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-02 06:42
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/24018; G11B7/24027; G11B7/007; G11B7/0079; G11B7/241; G11B7/004; G11B7/0045; G11B7/00452; G11B7/005; G11B7/0051; Y; Y10; Y10S; Y10S428/00; Y10S428/913; Y10S430/00; Y10S430/146; Y10T; Y10T428/00; Y10T428/24; Y10T428/24802; Y10T428/24917; Y10T428/31504; Y10T428/31678
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
114 words
An optical information recording medium of the type wherein recorded data are reproduced by scanning them with a laser beam, which comprises a ROM region where optically readable pits are already formed and an information recordable region where optically readable pits can be formed by irradiation with a writing laser beam, wherein the information recordable region comprises a light transmitting substrate having a deformable surface, a light absorptive layer overlaying the deformable surface, to absorb the writing laser beam, and a light reflective layer overlaying the light absorptive layer, said deformable surface being deformable by energy generated upon absorption of the writing laser beam by the light absorptive layer, to form optically readable pits.
Claim 2
Dependent Claim
114 words
An optical information recording medium of the type wherein recorded data are reproduced by scanning them with a laser beam, which comprises a ROM region where optically readable pits are already formed and an information recordable region where optically readable pits can be formed by irradiation with a writing laser beam, wherein the information recordable region comprises a light transmitting substrate having a deformable surface, a light absorptive layer overlaying the deformable surface, to absorb the writing laser beam, and a light reflective layer overlaying the light absorptive layer, said deformable surface being deformable by energy generated upon absorption of the writing laser beam by the light absorptive layer, to form optically readable pits.
Claim 3
Dependent Claim
40 words
The optical information recording medium according to Claim 1, wherein the light transmitting substrate has a heat distortion temperature within a range of from 85 to 200°C as measured in accordance with ASTM D648 under a load of 4.6 kg/cm².
Claim 4
Dependent Claim
35 words
The optical information recording medium according to Claim 1 or 2, wherein the light transmitting substrate has a Rockwell hardness within a range of from M200 to M75 as measured in accordance with ASTM D785.
Claim 5
Dependent Claim
30 words
The optical information recording medium according to any one of Claims 1 to 3, wherein the substrate is made of a polycarbonate resin, an acrylate resin or an epoxy resin.
Claim 6
Dependent Claim
23 words
The optical information recording medium according to any one of Claims 1 to 4, wherein the light absorptive layer contains a cyanine dye.
Claim 7
Dependent Claim
29 words
The optical information recording medium according to any one of Claims 1 to 5, wherein the reflective layer is made of gold, silver, copper, aluminum or an alloy thereof.
Claim 8
Dependent Claim
37 words
The optical information recording medium according to any one of Claims 1 to 6, wherein the deformable surface layer of the substrate has a tracking guide groove in which said optically readable pits are to be formed.
Claim 9
Dependent Claim
24 words
The optical information recording medium according to any one of Claims 1 to 7, wherein a protective layer is provided as a top layer.
References Cited (Backward Citations)
No citation records indexed.
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