Patent US4975358A successfully refreshed from Google Patents.
US4975358A
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Immediate write, read, and erase optical storage medium and method of marking and erasing
Assignee: United States Department of the Navy
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Filing: 1989-10-17
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Granted: 1990-12-04
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Expires: 2009-10-17
Abstract
Abstract An optical data storage medium comprises a substrate layer, a recording medium and an optional protective layer. The substrate layer supports the recording medium. The recording medium comprises a polymer having stable amorphous and crystalline states under human operating conditions which states have different optical properties. The recording medium is optionally covered and protected by a protective layer. The substrate, recording medium and protective layer can be formed from the same or different polymers. The data is stored by exposing the recording medium to patterned infra-red radiation. The radiation can be patterned by a mask, movement of the radiation beam or by other means to imprint the data on the recording medium.
Inventors
- 👤 Mark F. Sonnenschein
- 👤 Charles M. Roland
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 20:17
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/241; G11B7/252; G11B7/253; G11B7/242; G11B7/244; G11B7/245; G11B7/254; Y; Y10; Y10S; Y10S430/00; Y10S430/146
Claims Analysis
Total Claims: 32
Claim 1
Independent Claim
112 words
An optical storage medium comprising a substrate, and a recording medium on said substrate, wherein said recording medium is comprised of a polymer having the following combination of properties--(i) a glass transition temperature that is higher than room temperature, (ii) a crystalline melting temperature that is at least 50° higher than the glass transition temperature, (iii) a capacity for crystallizing to an extent sufficient to enable optical detection, (iv) crystallization kinetic behavior enabling the material to be obtained and maintained indefinitely in the amorphous state, and (v) thermal properties and crystallization rates and temperature dependencies such that crystallization can be effected by localized heating without crystallization spreading to regions not directly heated.
Claim 2
Dependent Claim
112 words
An optical storage medium comprising a substrate, and a recording medium on said substrate, wherein said recording medium is comprised of a polymer having the following combination of properties--(i) a glass transition temperature that is higher than room temperature, (ii) a crystalline melting temperature that is at least 50° higher than the glass transition temperature, (iii) a capacity for crystallizing to an extent sufficient to enable optical detection, (iv) crystallization kinetic behavior enabling the material to be obtained and maintained indefinitely in the amorphous state, and (v) thermal properties and crystallization rates and temperature dependencies such that crystallization can be effected by localized heating without crystallization spreading to regions not directly heated.
Claim 3
Dependent Claim
19 words
An optical storage medium according to claim 1 wherein the substrate and recording medium are the same polymeric material.
Claim 4
Dependent Claim
24 words
An optical storage medium according to claim 1 wherein the recording medium is protected by a protective layer of an optically clear protective covering.
Claim 5
Dependent Claim
23 words
An optical storage medium according to claim 3 wherein the recording medium and the protective layer is formed from the same polymeric material.
Claim 6
Dependent Claim
25 words
An optical storage medium according to claim 3 wherein the recording medium, the substrate and the protective layer is formed from the same polymeric material.
Claim 7
Dependent Claim
27 words
An optical storage medium according to claim 1 wherein the recording medium is selected from the group consisting of poly(ethyleneterephthalate) (PET), poly(aryl-ether-ether-ketone) (PEEK), and isotactic polystyrene (IPS).
Claim 8
Dependent Claim
27 words
An optical storage medium according to claim 2 wherein the recording medium is selected from the group consisting of poly(ethyleneterephthalate) (PET), poly(aryl-ether-ether-ketone) (PEEK), and isotactic polystyrene (IPS).
Claim 9
Dependent Claim
27 words
An optical storage medium according to claim 3 wherein the recording medium is selected from the group consisting of poly(ethyleneterephthalate) (PET), poly(aryl-ether-ether-ketone) (PEEK), and isotactic polystyrene (IPS).
Claim 10
Dependent Claim
27 words
An optical storage medium according to claim 5 wherein the recording medium is selected from the group consisting of poly(ethyleneterephthalate) (PET), poly(aryl-ether-ether-ketone) (PEEK), and isotactic polystyrene (IPS).
Claim 11
Dependent Claim
14 words
An optical storage medium according to claim 6 wherein the recording medium is poly(ethyleneterephthalate).
Claim 12
Dependent Claim
14 words
An optical storage medium according to claim 7 wherein the recording medium is poly(ethyleneterephthalate).
Claim 13
Dependent Claim
14 words
An optical storage medium according to claim 8 wherein the recording medium is poly(ethyleneterephthalate).
Claim 14
Dependent Claim
14 words
An optical storage medium according to claim 9 wherein the recording medium is poly(ethyleneterephthalate).
Claim 15
Dependent Claim
14 words
An optical storage medium according to claim 6 wherein the recording medium is polyaryletheretherketone.
Claim 16
Dependent Claim
14 words
An optical storage medium according to claim 7 wherein the recording medium is polyaryletheretherketone.
Claim 17
Dependent Claim
14 words
An optical storage medium according to claim 8 wherein the recording medium is polyaryletheretherketone.
Claim 18
Dependent Claim
14 words
An optical storage medium according to claim 9 wherein the recording medium is polyaryletheretherketone.
Claim 19
Dependent Claim
15 words
An optical storage medium according to claim 6 wherein the recording medium is isotactic polystyrene.
Claim 20
Dependent Claim
15 words
An optical storage medium according to claim 7 wherein the recording medium is isotactic polystyrene.
Claim 21
Dependent Claim
15 words
An optical storage medium according to claim 8 wherein the recording medium is isotactic polystyrene.
Claim 22
Dependent Claim
15 words
An optical storage medium according to claim 9 wherein the recording medium is isotactic polystyrene.
Claim 23
Dependent Claim
49 words
A process of forming an erasable image on an optical storage medium comprising exposing a recording medium consisting of an initially amorphous, optically clear polymeric film to infrared radiation in a predetermined area, causing a local heating of the film sufficient to transform the polymer to the crystalline state.
Claim 24
Dependent Claim
49 words
A process of forming an erasable image on an optical storage medium comprising exposing a recording medium consisting of an initially amorphous, optically clear polymeric film to infrared radiation in a predetermined area, causing a local heating of the film sufficient to transform the polymer to the crystalline state.
Claim 25
Dependent Claim
77 words
A process of forming an erasable image on an optical storage medium comprising exposing an initially crystalline, optically opaque or birefringent polymeric film to infrared radiation to effect local heating of the film said heating being sufficient to effect a local transformation of the polymer to the amorphous state, halting the irradiation, cooling said film sufficently to reduce the temperature of the heated area of the film below the glass transition temperature of the polymer without recrystallizing.
Claim 26
Dependent Claim
77 words
A process of forming an erasable image on an optical storage medium comprising exposing an initially crystalline, optically opaque or birefringent polymeric film to infrared radiation to effect local heating of the film said heating being sufficient to effect a local transformation of the polymer to the amorphous state, halting the irradiation, cooling said film sufficently to reduce the temperature of the heated area of the film below the glass transition temperature of the polymer without recrystallizing.
Claim 27
Dependent Claim
12 words
The process described in claim 22 wherein the film consists of poly(ethyleneterephthalate).
Claim 28
Dependent Claim
12 words
The process described in claim 23 wherein the film consists of poly(ethyleneterephthalate).
Claim 29
Dependent Claim
12 words
The process described in claim 22 wherein the film consists of polyaryletheretherketone.
Claim 30
Dependent Claim
12 words
The process described in claim 23 wherein the film consists of polyaryletheretherketone.
Claim 31
Dependent Claim
13 words
The process described in claim 22 wherein the film consists of isotactic polystyrene.
Claim 32
Dependent Claim
13 words
The process described in claim 23 wherein the film consists of isotactic polystyrene.
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) | 1993-12-03 | 1994-06-04 | 1994-12-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-12-03 | 1998-06-04 | 1998-12-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-12-03 | 2002-06-04 | 2002-12-04 | $7700.00 | Window Closed / Lapsed |