EP0120539A1
Expired / Lapsed
EP
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Optical recording disc
Assignee: Koninklijke Philips NV
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Filing: 1984-03-21
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Granted: —
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Expires: 2004-03-21
Abstract
Abstract Optically readable information disc having a glass substrate plate (1) and a recording layer (3) in which on the side of the recording layer the surface of the substrate plate is provided with a transparent layer (2) of a material which impedes the diffusion of Na and/or K from the substrate plate to the recording layer or in which the said surface is provided with a transparent layer of a cross-linked synthetic resin on which the layer of the diffusion-impeding material is provided.
Inventors
- 👤 Bernardus Antonius J. Jacobs
- 👤 Wilhelmus Gertrudes V. M. Rippens
- 👤 Adriaan Wilhelmus De Poorter
- 👤 Leendert Vriens
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 19:15
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/241; G11B7/252; G11B7/257; G11B7/2578; G11B7/242; G11B7/243; G11B2007/24302; G11B2007/24314; G11B2007/24316; G11B2007/24318; G11B2007/24324; G11B2007/25705; G11B2007/25706; G11B2007/25708; G11B2007/2571; G11B2007/25713; G11B2007/25715; G11B2007/25718; G11B7/253; G11B7/2531; G11B7/256
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
130 words
Optical recording disc having a glass substrate plate which on one side has a recording layer in which optically readable information bits can be formed by exposure to pulsated laser light which is focused on the recording layer via the substrate plate, characterized in that a transparent layer of a material which impedes the diffusion of Na and/or K from the substrate plate to the recording layer is provided directly on the surface of the substrate on the side of the recording layer, in which transparent layer no information bits are formed, or that the surface of the substrate plate is first provided with a transparent layer of a cross-linked synthetic resin and the above layer of a material which impedes the diffusion of Na and/or K is provided hereon.
Claim 2
Dependent Claim
130 words
Optical recording disc having a glass substrate plate which on one side has a recording layer in which optically readable information bits can be formed by exposure to pulsated laser light which is focused on the recording layer via the substrate plate, characterized in that a transparent layer of a material which impedes the diffusion of Na and/or K from the substrate plate to the recording layer is provided directly on the surface of the substrate on the side of the recording layer, in which transparent layer no information bits are formed, or that the surface of the substrate plate is first provided with a transparent layer of a cross-linked synthetic resin and the above layer of a material which impedes the diffusion of Na and/or K is provided hereon.
Claim 3
Dependent Claim
28 words
An optical recording disc as claimed in Claim 1, characterized in that a transparent, diffusion-impeding or diffusion-inhibiting layer is used manufactured from an inorganic oxide, nitride or fluoride.
Claim 4
Dependent Claim
38 words
An optical recording disc as claimed in Claim 2, characterized in that the transparent layer is manufactured from a nitride or oxide of Ti or Si , an oxide of Al, Y or Ge or from calcium fluoride.
Claim 5
Dependent Claim
18 words
An optical recording disc as claimed in Claim 1, characterized in that the recording layer comprises a chalcogenide.
Claim 6
Dependent Claim
61 words
An optical recording disc as claimed in Claim 1, characterized in that the surface of the substrate plate is first provided with the transparent diffusion-impeding layer, a transparent layer of a cross-linked synthetic resin is provided hereon in which an optically readable guide track is present and a recording layer is provided on the transparent layer of the cross-linked synthetic resin.
References Cited (Backward Citations)
FR2266933A1
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JPS5352104A
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FR2418514A1
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EP0023809A1
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EP0045183A2
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JPS57109696A
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JPS57128596A
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EP0059096A2
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