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US4318112A Expired / Lapsed US ⏱️ 0.0 years remaining

Optical recording disc

Assignee: US Philips Corp
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Filing: 1979-11-29
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Granted: 1982-03-02
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Expires: 1999-11-29
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Abstract

Abstract An optical recording disc which comprises a disc-shaped substrate plate, for example, a plate manufactured from synthetic resin, for example, polymethylmethacrylate, which has on at least one side an ablative recording layer, for example, an amorphorous layer of a tellurium mixture, in which the substrate on the side of the recording layer has extrinsic instabilities, in particular surface discontinuities. For example, the surface of the substrate is roughened or provided with scratches. The substrate may also be provided with a separate coating layer comprising the discontinuities, for example, an inhomogeneous vapor-deposited layer, a coarse-granular layer of a dye, or a light-cured lacquer layer which has been roughened or provided with scratches.

Inventors

  • 👤 Petrus J. Kivits
  • 👤 Marinus R. J. de Bont
  • 👤 Adriaan W. De Poorter

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 19:10
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/241; G11B7/252; G11B7/253; G11B7/242; G11B7/243; G11B2007/24302; G11B2007/24314; G11B2007/24316; G11B7/2531; G11B7/2533; G11B7/257; G11B7/2572; G11B7/2575; Y; Y10; Y10S; Y10S430/00; Y10S430/146; Y10S430/165

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 99 words
An optical recording device in which information can be recorded and read optically comprising a substrate having on at least one side an ablative recording layer which upon exposure to energy-rich light modulated according to the information melts in exposed places and forms holes characterized in that at the surface of the substrate facing the recording layer there is present a surface discontinuity having a diametrical dimension of 30 to 300 nm and a level difference with the substrate surface of 8 to 80 nm, the recording layer having a thickness in the order of magnitude of 30-40 nm.
Claim 2
Dependent Claim 99 words
An optical recording device in which information can be recorded and read optically comprising a substrate having on at least one side an ablative recording layer which upon exposure to energy-rich light modulated according to the information melts in exposed places and forms holes characterized in that at the surface of the substrate facing the recording layer there is present a surface discontinuity having a diametrical dimension of 30 to 300 nm and a level difference with the substrate surface of 8 to 80 nm, the recording layer having a thickness in the order of magnitude of 30-40 nm.
Claim 3
Dependent Claim 46 words
An optical recording device as claimed in claim 1, characterized in that the substrate is transparent and contains, on the surface facing the recording layer an optical reading servo track having a relief structure of servo areas situated alternatively at a higher and a lower level.
Claim 4
Dependent Claim 60 words
An optical recording device as claimed in claim 1, characterized in that the substrate is a substrate manufactured from a synthetic resin or glass whose surface adjoining the recording layer has been roughened or provided with scratches chemically or mechanically or whose surface adjoining the recording layer is a copy of the surface of a matrix comprising the surface discontinuity.
Claim 5
Dependent Claim 29 words
An optical recording device as claimed in claim 1, characterized in that on the side of the recording layer the substrate has a coating layer comprising the surface discontinuity.
Claim 6
Dependent Claim 20 words
An optical recording device as claimed in claim 4, characterized in that the coating layer is non-continuous, inhomogeneous vapour-deposited layer.
Claim 7
Dependent Claim 22 words
An optical recording device as claimed in claim 4, characterized in that the coating layer is a coarse-granular vapour-deposited layer of dye.
Claim 8
Dependent Claim 60 words
An optical recording device as claimed in claim 4, characterized in that the coating layer is a light-cured lacquer layer of which the surface adjoining the recording layer has been roughened or provided with scratches mechanically or chemically or of which the surface adjoining the recording layer is a copy of the surface of a matrix comprising the surface discontinuity.
Claim 9
Dependent Claim 23 words
An optical recording device as claimed in claim 7, characterized in that the light-cured lacquer layer also comprises an optically readable servo track.

References Cited (Backward Citations)

US3861952A Cited
US4032691A Cited
US3889272A Cited
US4175145A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1985-03-01 1985-08-31 1986-03-02 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1989-03-01 1989-08-31 1990-03-02 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1993-03-01 1993-08-31 1994-03-02 $7700.00 Window Closed / Lapsed

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