US4956243A
Expired / Lapsed
US
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Optical memory element
Assignee: Sharp Corp
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Filing: 1987-01-30
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Granted: 1990-09-11
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Expires: 2007-01-30
Abstract
Abstract An optical memory element contains first and second reflector films, wherein the first reflector film is made of a material of a sufficiently large light reflectance in a relative sense as compared to the second reflector film, and the second reflector film being made of a material of a sufficiently small thermal conductivity in a relative sense as compared to the first reflector film.
Inventors
- 👤 Tomoyuki Miyake
- 👤 Yoshiteru Murakami
- 👤 Hiroyuki Katayama
- 👤 Akira Takahashi
- 👤 Kenji Ohta
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:15
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/241; G11B7/252; G11B7/258; G11B11/00; G11B11/10; G11B11/105; G11B11/10582; G11B11/10586; G11B11/10589; G11B13/00; G11B13/04; G11B13/045; G11B7/242; G11B7/243; G11B2007/24302; G11B2007/24306; G11B7/257; G11B2007/25705; G11B2007/25708; G11B2007/25713; G11B7/253; G11B7/2531; G11B7/2533; G11B7/2534; G11B7/2585; G11B7/259; G11B7/2595; Y; Y10; Y10S; Y10S428/00; Y10S428/90
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
116 words
A magneto-optical memory element comprising: a substrate; a magneto-optical recording medium film formed on said substrate; and a reflector film having first and second reflector layers, wherein said first reflector layer is formed on said recording medium and comprises a material of a higher optical reflectance in a relative sense than said second reflector layer, and wherein said second reflector layer is formed on said first reflector layer and comprises a material of a smaller thermal conductivity in a relative sense than said first reflector layer, and wherein said second reflector layer comprises a material of low thermal conductivity selected from the group consisting of Ni, Th, Ta, Pb, Zr, Bi, Te, Se and AlNi alloy.
Claim 2
Dependent Claim
116 words
A magneto-optical memory element comprising: a substrate; a magneto-optical recording medium film formed on said substrate; and a reflector film having first and second reflector layers, wherein said first reflector layer is formed on said recording medium and comprises a material of a higher optical reflectance in a relative sense than said second reflector layer, and wherein said second reflector layer is formed on said first reflector layer and comprises a material of a smaller thermal conductivity in a relative sense than said first reflector layer, and wherein said second reflector layer comprises a material of low thermal conductivity selected from the group consisting of Ni, Th, Ta, Pb, Zr, Bi, Te, Se and AlNi alloy.
Claim 3
Dependent Claim
34 words
The magneto-optical memory element of claim 1, further comprising a dielectric film formed at least between said substrate and said magneto-optical recording medium film or between said recording medium film and said reflector film.
Claim 4
Dependent Claim
37 words
The magneto-optical memory element of claim 1, further comprising: a first dielectric film formed between said substrate and said magneto-optical recording medium; and a second dielectric film formed between said recording medium and said first reflector layer.
Claim 5
Dependent Claim
65 words
The magneto-optical memory element of claim 3, wherein said first reflector layer comprises a material of high reflectance selected from the group consisting of Al, Cu, Au, Ag, cyanine type pigment, merocyanine pigment, and dioxazine; and wherein said second reflector layer comprises a material of low thermal conductivity selected from the group consisting of Ni, Th, Ta, Pb, Zr, Bi, Te, Se and AlNi alloy.
Claim 6
Dependent Claim
55 words
The magneto-optical memory element of claim 4, wherein said substrate comprises glass, polycarbonate, acrylic, or epoxy resin; said magneto-optical recording medium comprises a rare earth metal-transition metal alloy selected from the group consisting of GdTbFe, GdTbFeCo, TbFe and TbFeCo; and said first and second dielectric films comprise AlN, SiN, ZnN, SiO, or SiO 2 .
Claim 7
Dependent Claim
21 words
The magneto-optical memory element of claim 3, wherein said first reflector layer comprises Al and said second reflector layer comprises Ni.
Claim 8
Dependent Claim
55 words
The magneto-optical memory element of claim 3, wherein said substrate comprises glass, polycarbonate, acrylic, or epoxy resin; said magneto-optical recording medium comprises a rare earth metal-transition metal alloy selected from the group consisting of GdTbFe, GdTbFeCo, TbFe and TbFeCo; and said first and second dielectric films comprises AlN, SiN, ZnN, SiO, or SiO 2 .
Claim 9
Dependent Claim
35 words
The magneto-optical memory element of claim 3, wherein said magneto-optical recording medium comprises GdTbFe, said first and second dielectric layers comprise AlN, said first reflector layer comprises Al, and said second reflector layer comprises Ni.
Claim 10
Dependent Claim
64 words
The magneto-optical memory element of claim 8, wherein said first dielectric layer has a thickness of about 800 angstroms, said magneto-optical recording medium has a thickness of about 200 angstroms, said second dielectric layer has a thickness of about 250 angstroms, said first reflector layer has a thickness of about 100 angstroms and said second reflector layer has a thickness of about 500 angstroms.
Claim 11
Dependent Claim
35 words
The magneto-optical memory element of claim 1, wherein said first reflector layer comprises a material of high reflectance selected from the group consisting of Al, Cu, Au, Ag, cyanine type pigment, merocyanine pigment and dioxazine.
Claim 12
Dependent Claim
36 words
The magneto-optical memory element of claim 10, wherein said second reflector layer comprises a material of low thermal conductivity selected from the group consisting of Ni, Th, Ta, Pb, Zr, Bi, Te, Se and AlNi alloy.
Claim 13
Dependent Claim
21 words
The magneto-optical memory element of claim 1, wherein said first reflector layer comprises Al and said second reflector layer comprises Ni.
Claim 14
Dependent Claim
55 words
The magneto-optical memory element of claim 1, wherein said substrate comprises glass, polycarbonate, acrylic, or epoxy resin; said magneto-optical recording medium comprises a rare earth metal-transition metal alloy selected from the group consisting of GdTbFe, GdTbFeCo, TbFe and TbFeCo; and said first and second dielectric films comprises AlN, SiN, ZnN, SiO, or SiO 2 .
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1993-09-10 | 1994-03-12 | 1994-09-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-09-10 | 1998-03-12 | 1998-09-11 | $3760.00 | Window Closed / Lapsed |
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