EP0058496A2
Expired / Lapsed
EP
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Protuberant optical recording medium
Assignee: 3M Co
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Filing: 1982-02-04
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Granted: —
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Expires: 2002-02-04
Abstract
Abstract An optical recording medium as shown in Figure 3 containing a light-absorbing film 32 of refractory material less than 60 nm thick and which is sufficiently plastic to allow plastic information upon localized heating is provided for exposure to a focused laser beam 20, whereupon localized heating of the light-absorbing film enables information storage in the form of localized protuberances 38 in the heated areas which can subsequently be optically detected and can be used as a master information record for replication purposes.
Inventors
- 👤 Kent N. Maffitt
- 👤 William B. Robbins
- 👤 Richard F. Willson
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-23 17:25
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/004; G11B7/0045; G11B7/00452; G11B7/24; G11B7/2403; G11B7/24067; G11B7/241; G11B7/242; G11B7/243; G11B7/252; G11B7/257; G11B7/2572; G11B2007/24302; G11B2007/24312; G11B2007/24318; G11B2007/24328; G11B7/2433; G11B7/244; G11B7/245; G11B7/258; G11B7/2585; Y; Y10; Y10S; Y10S430/00; Y10S430/146
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
100 words
A recording medium for use with a focused laser beam, said recording medium having a substrate and a light-absorbing layer adjacent thereto for absorbing light from the laser beam in localized regions to thereby provide information storage, characterized by said light-absorbing layer comprising a refractory material selected from the group consisting of amorphous carbon, boron and silicon and alloys therebetween, and having a thickness of less than 60 nm and a plasticity sufficient to allow plastic deformation upon localized heating resulting from impingement by said laser beam to enable the formation of localized protuberances which can subsequently be optically detected.
Claim 2
Dependent Claim
100 words
A recording medium for use with a focused laser beam, said recording medium having a substrate and a light-absorbing layer adjacent thereto for absorbing light from the laser beam in localized regions to thereby provide information storage, characterized by said light-absorbing layer comprising a refractory material selected from the group consisting of amorphous carbon, boron and silicon and alloys therebetween, and having a thickness of less than 60 nm and a plasticity sufficient to allow plastic deformation upon localized heating resulting from impingement by said laser beam to enable the formation of localized protuberances which can subsequently be optically detected.
Claim 3
Dependent Claim
58 words
A recording medium according to claim 1, further characterized by a reflecting layer between said substrate and said light-absorbing layer, and wherein the total optical thickness of the absorbing layer is such as to result in an interferometric, substantially antireflecting structure when in the undeformed state, and wherein the subsequently formed protuberances possess appreciably increased effective optical thickness.
Claim 4
Dependent Claim
30 words
A recording medium according to claim 2, further characterized by a primer layer between said substrate and said reflecting layer for enhancing the nucleation and adhesion of said reflecting layer.
Claim 5
Dependent Claim
38 words
A recording medium according to either of claims 2 and 3, further characterized by an optical spacer layer between said reflecting layer and said light-absorbing layer, which in ccnbination with said light-absorbing layer provides said interferometric antireflecting structure.
Claim 6
Dependent Claim
34 words
A recording medium according to any one of claims -1 to 4, characterized by said light-absorbing layer comprising a layer of amorphous carbon having a thickness in the range of 7.5 to 30 nm.
Claim 7
Dependent Claim
19 words
A recording medium according to claim 4,. characterized by said optical spacer layer comprising a spin cast polymeric layer.
Claim 8
Dependent Claim
28 words
A recording medium according to either of claims 4 and 6, characterized by said optical spacer layer being formed of a polymeric material substantially transparent to said light.
Claim 9
Dependent Claim
43 words
A recording medium according to either of claims 4 and 6, characterized by, said optical spacer layer comprising the combination of a polymeric material and an organic dye such that greater than ten percent of light at a given wavelength is absorbed therein.
Claim 10
Independent Claim
124 words
A method for recording information in a thin film recording medium, characterized by the steps of (a) providing a recording medium having a substrate and a light-absorbing layer adjacent thereto, said layer including a refractory material selected from the group consisting of amorphous carbon, boron and silicon and alloys therebetween, nitrides of tantalum and oxides and suboxides of zirconium, and having a thickness of less than 60 nm and a plasticity sufficient to allow plastic deformation upon localized heating, (b) exposing said medium to a focused laser beam of limited power and duration to cause absorption of light therefrom in localized regions, and (c) deforming said absorbing layer as a result of said light absorption to form optically detectable protuberances at said localized regions.
Claim 11
Independent Claim
124 words
A method for recording information in a thin film recording medium, characterized by the steps of (a) providing a recording medium having a substrate and a light-absorbing layer adjacent thereto, said layer including a refractory material selected from the group consisting of amorphous carbon, boron and silicon and alloys therebetween, nitrides of tantalum and oxides and suboxides of zirconium, and having a thickness of less than 60 nm and a plasticity sufficient to allow plastic deformation upon localized heating, (b) exposing said medium to a focused laser beam of limited power and duration to cause absorption of light therefrom in localized regions, and (c) deforming said absorbing layer as a result of said light absorption to form optically detectable protuberances at said localized regions.
Claim 12
Dependent Claim
61 words
A method for recording information according to claim 9, characterized by said providing step further comprising providing a reflecting layer between said substrate and said light-absorbing layer, the total optical thickness of the absorbing layer being such as to result in an interferometric, substantially antireflecting structure when in the undeformed state, and wherein said protuberances possess appreciably increased effective optical thickness.
Claim 13
Dependent Claim
37 words
A method of recording information according to claim 10, characterized by said providing step further comprising providing a primer layer between said substrate and said reflecting layer for enhancing the nucleation and adhesion of said reflecting layer.
Claim 14
Dependent Claim
41 words
A method of recording information according to claim 10, characterized by said providing step further comprising providing an optical spacer layer between said reflecting layer and said light-absorbing layer, which in combination with. said light-absorbing layer provides said interferometric antireflecting structure.,
Claim 15
Dependent Claim
15 words
An information record made according to the process of any of claims 9 to 12.
References Cited (Backward Citations)
No citation records indexed.
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