Patent US4414650A successfully refreshed from Google Patents.
US4414650A
Expired / Lapsed
US
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Magneto-optic memory element
Assignee: Sharp Corp
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Filing: 1981-06-19
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Granted: 1983-11-08
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Expires: 2001-06-19
Abstract
Abstract A magneto-optic memory medium comprises a reflector exhibiting reflectance for light used for information reproduction and a magneto-optic magnetization film disposed on the reflector. When light is applied for information reproduction, the light impinges on the magnetization film and reaches the reflector. The light reflected through the reflector and the magnetization film is of use for information reproduction. In a preferred form of the magneto-optic memory medium, there is deposited on a transparent substrate a magnetic film having an axis of easy magnetization perpendicular to its surface. The magnetization film is overlaid with a reflective coating which is shaped into a strip configuration.
Inventors
- 👤 Kenji Ohta
- 👤 Akira Takahashi
- 👤 Toshihisa Deguchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 20:11
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/09; G03; G03G; G03G5/00; G03G5/16; G11; G11B; G11B11/00; G11B11/10; G11B11/105; G11B11/10582
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
86 words
A magneto-optic memory medium comprising: a reflector for reflecting light used for information reproduction; a magneto-optic magnetization film having an axis of magnetization perpendicular to its surface disposed adjacent said reflector; and means for directing light onto said magnetization film from a position on a side of said film opposite said reflector; wherein, when light is applied for information reproduction, the light passes through said magnetization film to said reflector and is reflected by the reflector back to said magnetization film for use in information reproduction.
Claim 2
Dependent Claim
86 words
A magneto-optic memory medium comprising: a reflector for reflecting light used for information reproduction; a magneto-optic magnetization film having an axis of magnetization perpendicular to its surface disposed adjacent said reflector; and means for directing light onto said magnetization film from a position on a side of said film opposite said reflector; wherein, when light is applied for information reproduction, the light passes through said magnetization film to said reflector and is reflected by the reflector back to said magnetization film for use in information reproduction.
Claim 3
Dependent Claim
89 words
A magneto-optic memory medium comprising: a reflector for reflecting light used for information reproduction; a magneto-optic magnetization film disposed adjacent said reflector; and means for directing light onto said magnetization film from a position on a side of said film opposite said reflector; wherein, when light is applied for information reproduction, the light passes through said magnetization film to said reflector and is reflected by the reflector back to said magnetization film for use in information reproduction; wherein said reflector comprises a plurality of strip portions defining guide tracks.
Claim 4
Dependent Claim
89 words
A magneto-optic memory medium comprising: a reflector for reflecting light used for information reproduction; a magneto-optic magnetization film disposed adjacent said reflector; and means for directing light onto said magnetization film from a position on a side of said film opposite said reflector; wherein, when light is applied for information reproduction, the light passes through said magnetization film to said reflector and is reflected by the reflector back to said magnetization film for use in information reproduction; wherein said reflector comprises a plurality of strip portions defining guide tracks.
Claim 5
Dependent Claim
77 words
A magneto-optic memory medium comprising: a reflector for reflecting light used for information reproduction; a magneto-optic magnetization film spaced from said reflector; and means for directing lgiht onto said magnetization film from a position on a side of said film opposite said reflector; wherein, when light is applied for information reproduction, the light passes through said magnetization film to said reflector and is reflected by the reflector back to said magnetization film for use in information reproduction.
Claim 6
Dependent Claim
77 words
A magneto-optic memory medium comprising: a reflector for reflecting light used for information reproduction; a magneto-optic magnetization film spaced from said reflector; and means for directing lgiht onto said magnetization film from a position on a side of said film opposite said reflector; wherein, when light is applied for information reproduction, the light passes through said magnetization film to said reflector and is reflected by the reflector back to said magnetization film for use in information reproduction.
Claim 7
Dependent Claim
88 words
A magneto-optic memory medium comprising: a reflector for reflecting light used for information reproduction; a magneto-optic magnetization film disposed adjacent said reflector; an optically transparent layer between said reflector and said magnetization film; and means for directing light onto said magnetization film from a position on a side of said film opposite said reflector; wherein, when light is applied for information reproduction, the light passes through said magnetization film to said reflector and is reflected by the reflector back to said magnetization film for use in information reproduction.
Claim 8
Dependent Claim
88 words
A magneto-optic memory medium comprising: a reflector for reflecting light used for information reproduction; a magneto-optic magnetization film disposed adjacent said reflector; an optically transparent layer between said reflector and said magnetization film; and means for directing light onto said magnetization film from a position on a side of said film opposite said reflector; wherein, when light is applied for information reproduction, the light passes through said magnetization film to said reflector and is reflected by the reflector back to said magnetization film for use in information reproduction.
References Cited (Backward Citations)
US3872451A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-11-07 | 1987-05-09 | 1987-11-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-11-07 | 1991-05-09 | 1991-11-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-11-07 | 1995-05-09 | 1995-11-08 | $7700.00 | Window Closed / Lapsed |