US4801499A
Expired / Lapsed
US
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Optical recording medium
Assignee: Seiko Epson Corp
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Filing: 1986-01-17
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Granted: 1989-01-31
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Expires: 2006-01-17
Abstract
Abstract A magneto-optic recording medium including a transparent substrate and a non-oxide dielectric layer formed thereon is provided. The dielectric layer includes a first dielectric material of the type which exhibits cracks running in a generally radial direction when deposited on a surface and which is designated dielectric Group A and a second dielectric material which exhibits cracks running in a generally tangential direction when deposited on a surface and which is designated dielectric Group B. The dielectric layer may be separate layers or a mixture of the two dielectric materials.
Inventors
- 👤 Akira Aoyama
- 👤 Shigeru Kogure
- 👤 Mamoru Sugimoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:26
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/26; G11B11/00; G11B11/10; G11B11/105; G11B11/10582; G11B7/241; G11B7/252; G11B7/257; G11B7/2578; G11B2007/25705; G11B2007/25706; G11B2007/25708; G11B2007/2571; G11B2007/25711; G11B2007/25713; G11B2007/25716; G11B7/253; G11B7/2531; G11B7/2533; G11B7/2534; G11B7/258; G11B7/2585; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/26; Y10T428/263; Y10T428/264; Y10T428/265
Claims Analysis
Total Claims: 31
Claim 1
Independent Claim
81 words
A magneto-optic recording medium comprising: a transparent substrate; a non-oxide dielectric layer formed on the substrate, the dielectric layer including at least one layer of a first dielectric material selected from the group consisting of aluminum nitride and silicon carbide and at least one layer of a second dielectric material selected from the group consisting of silicon nitride, zinc sulfide, titanium nitride, zirconium nitride, hafnium nitride, titanium carbide and zirconium carbide; and a magneto-optic recording layer formed on the dielectric layer.
Claim 2
Dependent Claim
81 words
A magneto-optic recording medium comprising: a transparent substrate; a non-oxide dielectric layer formed on the substrate, the dielectric layer including at least one layer of a first dielectric material selected from the group consisting of aluminum nitride and silicon carbide and at least one layer of a second dielectric material selected from the group consisting of silicon nitride, zinc sulfide, titanium nitride, zirconium nitride, hafnium nitride, titanium carbide and zirconium carbide; and a magneto-optic recording layer formed on the dielectric layer.
Claim 3
Dependent Claim
20 words
The recording medium of claim 1, further including a reflecting film disposed on the surface of the magneto-optic recording layer.
Claim 4
Dependent Claim
12 words
The recording medium of claim 1, wherein the reflecting film is aluminum.
Claim 5
Dependent Claim
26 words
The recording medium of claim 1, further including a second dielectric layer for enhancing the effect of a laser beam deposited on the magneto-optic recording layer.
Claim 6
Dependent Claim
36 words
The recording medium of claim 2, further including a second dielectric layer for enhancing the effect of a laser beam deposited on the magneto-optic recording layer and a reflecting film formed on the second dielectric layer.
Claim 7
Dependent Claim
26 words
The recording medium of claim 1, wherein the dielectric layer includes at least one layer of aluminum nitride and at least one layer of silicon nitride.
Claim 8
Dependent Claim
19 words
The recording medium of claim 1, wherein the thickness of the dielectric layer is less than about 2000 Å.
Claim 9
Dependent Claim
38 words
The recording medium of claim 1, wherein the dielectric layer includes a first layer of aluminum nitride on the substrate, a layer of silicon nitride thereon and a second layer of aluminum nitride on the silicon nitride layer.
Claim 10
Dependent Claim
31 words
The recording medium of claim 1, wherein information is recorded onto, reproduced from and erased from the magneto-optic recording layer by irradiation of the magnetooptic recording layer with condensed laser light.
Claim 11
Dependent Claim
15 words
The recording medium of claim 1, wherein the magneto-optic recording layer is a gadolinium-terbiumiron-cobalt layer.
Claim 12
Dependent Claim
14 words
The recording medium of claim 1, wherein the transparent substrate is a polymethylmethacrylate substrate.
Claim 13
Dependent Claim
14 words
The recording medium of claim 1, wherein the transparent substrate is a polycarbonate substrate.
Claim 14
Dependent Claim
21 words
The recording medium of claim 1, wherein the substrate is a glass substrate having an ultraviolet curing resin layer formed thereon.
Claim 15
Dependent Claim
21 words
The recording medium of claim 1, wherein the surface of the substrate facing the dielectric layer is formed with guide grooves.
Claim 16
Dependent Claim
45 words
The magneto-optic recording medium of claim 1, wherein at least one layer of the first dielectric material is formed on the substrate and at least one layer of the second dielectric material is formed on the at least one layer of the first dielectric material.
Claim 17
Dependent Claim
46 words
The magneto-optic recording medium of claim 1, wherein the dielectric layer is formed from a first layer of the first dielectric material disposed on the transparent substrate and a second layer of the second dielectric material disposed on the first layer of the first dielectric material.
Claim 18
Dependent Claim
46 words
The magneto-optic recording medium of claim 1, wherein the dielectric layer is formed from a first layer of the second dielectric material disposed on the transparent substrate and a second layer of the first dielectric material disposed on the first layer of the second dielectric material.
Claim 19
Dependent Claim
77 words
A magneto-optic recording medium comprising: a transparent substrate; a non-oxide dielectric layer formed on the substrate, the dielectric layer formed of a mixture of at least one first dielectric material selected from the group consisting of aluminum nitride and silicon carbide and at least one second dielectric material selected from the group consisting of zinc sulfide, titanium nitride, zirconium nitride, hafnium nitride, titanium carbide and zirconium carbide; and a magneto-optic recording layer formed on the dielectric layer.
Claim 20
Dependent Claim
77 words
A magneto-optic recording medium comprising: a transparent substrate; a non-oxide dielectric layer formed on the substrate, the dielectric layer formed of a mixture of at least one first dielectric material selected from the group consisting of aluminum nitride and silicon carbide and at least one second dielectric material selected from the group consisting of zinc sulfide, titanium nitride, zirconium nitride, hafnium nitride, titanium carbide and zirconium carbide; and a magneto-optic recording layer formed on the dielectric layer.
Claim 21
Dependent Claim
20 words
The recording medium of claim 18, further including a reflecting film disposed on the surface of the magneto-optic recording layer.
Claim 22
Dependent Claim
12 words
The recording medium of claim 19, wherein the reflecting film is aluminum.
Claim 23
Dependent Claim
26 words
The recording medium of claim 18, further including a second dielectric layer for enhancing the effect of a laser beam deposited on the magneto-optic recording layer.
Claim 24
Dependent Claim
36 words
The recording medium of claim 18, further including a second dielectric layer for enchancing the effect of a laser beam deposited on the magneto-optic recording layer and a reflecting film formed on the second dielectric layer.
Claim 25
Dependent Claim
19 words
The recording medium of claim 18, wherein the thickness of the dielectric layer is less than about 2000 Å.
Claim 26
Dependent Claim
31 words
The recording medium of claim 18, wherein information is recorded onto, reproduced from and erased from the magneto-optic recording layer by irradiation of the magneto-optic recording layer with condensed laser light.
Claim 27
Dependent Claim
15 words
The recording medium of claim 18, wherein the magneto-optic recording layer is a gadolinium-terbium-iron-cobalt layer.
Claim 28
Dependent Claim
14 words
The recording medium of claim 18, wherein the transparent substrate is a polymethylmethacrylate substrate.
Claim 29
Dependent Claim
14 words
The recording medium of claim 18, wherein the transparent substrate is a polycarbonate substrate.
Claim 30
Dependent Claim
21 words
The recording medium of claim 18, wherein the substrate is a glass substrate having an ultraviolet curing resin layer formed thereon.
Claim 31
Dependent Claim
21 words
The recording medium of claim 18, wherein the surface of the substrate facing the dielectric layer is formed with guide grooves.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-01-31 | 1992-08-01 | 1993-01-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-01-31 | 1996-08-01 | 1997-01-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-01-31 | 2000-08-01 | 2001-01-31 | $7700.00 | Window Closed / Lapsed |