Patent US4655554A successfully refreshed from Google Patents.
US4655554A
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Spatial light modulator having a capacitively coupled photoconductor
Assignee: United States, AIR FORCE THE, Secretary of, Department of
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Filing: 1985-03-06
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Granted: 1987-04-07
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Expires: 2005-03-06
Abstract
Abstract A spatial light modulator in which the photoreceptor is a capacitively coupled semiconductor in the form of a silicon-silicon dioxide-transparent electrode structure.
Inventors
- 👤 David Armitage
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 23:26
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/135; G02F1/03; G02F1/0338
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
165 words
A spatial light modulator comprising: a semiconductor element comprising a semiconductor substrate having a first surface and an opposed second surface, a first transparent metallic electrode, a dielectric layer disposed between said first surface of said semiconductor substrate and a surface of said first transparent metallic electrode, and a charge-confining microgroove lattice structure formed in said second surface of said semiconductor substrate; a dielectric mirror having a first surface and an opposed second surface, said first surface of said dielectric mirror being adjacent said second surface of said semiconductor substrate; an electro-optic crystal having a first surface and an opposed second surface, said first surface of said electro-optic crystal being adjacent said second surface of said dielectric mirror; a second transparent electrode having a first surface and an opposed second surface, said first surface of said second transparent electrode being adjacent said second surface of said electro-optic crystal; and means for applying a voltage pulse between said first transparent electrode and said second transparent electrode.
Claim 2
Dependent Claim
165 words
A spatial light modulator comprising: a semiconductor element comprising a semiconductor substrate having a first surface and an opposed second surface, a first transparent metallic electrode, a dielectric layer disposed between said first surface of said semiconductor substrate and a surface of said first transparent metallic electrode, and a charge-confining microgroove lattice structure formed in said second surface of said semiconductor substrate; a dielectric mirror having a first surface and an opposed second surface, said first surface of said dielectric mirror being adjacent said second surface of said semiconductor substrate; an electro-optic crystal having a first surface and an opposed second surface, said first surface of said electro-optic crystal being adjacent said second surface of said dielectric mirror; a second transparent electrode having a first surface and an opposed second surface, said first surface of said second transparent electrode being adjacent said second surface of said electro-optic crystal; and means for applying a voltage pulse between said first transparent electrode and said second transparent electrode.
Claim 3
Dependent Claim
25 words
A spatial light modulator as defined in claim 1 and further comprising: a transparent supporting substrate adjacent said second surface of said second transparent electrode.
Claim 4
Dependent Claim
19 words
A spatial light modulator as defined in claim 1 wherein said electro-optic crystal is formed of lithium niobate material.
Claim 5
Dependent Claim
19 words
A spatial light modulator as defined in claim 1 wherein said electro-optic crystal is formed of liquid crystal material.
Claim 6
Dependent Claim
17 words
A spatial light modulator as defined in claim 1 wherein said semiconductor substrate is formed of silicon.
Claim 7
Dependent Claim
18 words
A spatial light modulator as defined in claim 5 wherein said dielectric layer is formed of silicon dioxide.
Claim 8
Dependent Claim
21 words
A spatial light modulator as defined in claim 6 wherein said silicon dioxide layer has a thickness of approximately 0.3 microns.
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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) | 1990-04-06 | 1990-10-06 | 1991-04-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-04-06 | 1994-10-06 | 1995-04-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-04-06 | 1998-10-06 | 1999-04-07 | $7700.00 | Window Closed / Lapsed |