US4037932A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrooptic-photoconductor sandwich using actinic readout light
Assignee: Xerox Corp
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Filing: 1976-05-03
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Granted: 1977-07-26
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Expires: 1996-05-03
Abstract
Abstract An optically addressed light valve is disclosed which is cabable of being read-out at very high light intensities during the write-in cycle without need for an optical blocking layer. The system is based on the combination of a reflective photoconductor and an electro-optically active medium and exploits the characteristics of space charge limited currents in photoconductors of high optical absorption of actinic wavelengths.
Inventors
- 👤 Werner E. L. Haas
- 👤 Gary A. Dir
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 07:19
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/03; G02F1/0338; G02F1/13; G02F1/133; G02F1/135
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
130 words
An imaging method comprising: a. providing, without an optical blocking layer therebetween, a photoconductive layer and an electro-optic medium in between two electrodes; b. applying a voltage between said two electrodes; c. striking said photoconductive layer from one side with actinic radiation in imagewise configuration; and d. uniformly striking said photoconductive layer from its other side with actinic radiation which is absorbed by said photoconductive layer in an amount effective to limit the intensity of uniform actinic radiation transmitted through said photoconductive layer no greater than about one-third of the intensity of said imagewise configured actinic radiation striking said one side of said photoconductive layer; wherein the amount of uniform actinic radiation absorbed by said photoconductive layer is sufficient to create a space charge limited current within said photoconductive layer.
Claim 2
Dependent Claim
130 words
An imaging method comprising: a. providing, without an optical blocking layer therebetween, a photoconductive layer and an electro-optic medium in between two electrodes; b. applying a voltage between said two electrodes; c. striking said photoconductive layer from one side with actinic radiation in imagewise configuration; and d. uniformly striking said photoconductive layer from its other side with actinic radiation which is absorbed by said photoconductive layer in an amount effective to limit the intensity of uniform actinic radiation transmitted through said photoconductive layer no greater than about one-third of the intensity of said imagewise configured actinic radiation striking said one side of said photoconductive layer; wherein the amount of uniform actinic radiation absorbed by said photoconductive layer is sufficient to create a space charge limited current within said photoconductive layer.
Claim 3
Dependent Claim
15 words
The method according to claim 1 wherein said electro-optic medium comprises a liquid crystalline composition.
Claim 4
Dependent Claim
18 words
The method according to claim 2 wherein said liquid crystalline composition undergoes the cholesteric to nematic phase transition.
Claim 5
Dependent Claim
18 words
The method according to claim 3 further including the step of removing the voltage applied in step (b).
Claim 6
Dependent Claim
24 words
The method according to claim 4 further including the step of applying a voltage subsequent to removal of the voltage applied in step (b).
Claim 7
Dependent Claim
14 words
The method according to claim 2 wherein said liquid crystalline composition undergoes dynamic scattering.
Claim 8
Dependent Claim
14 words
The method of claim 2 wherein said liquid crystalline composition comprises a twisted nematic.
Claim 9
Dependent Claim
14 words
The method of claim 2 wherein said liquid crystalline composition undergoes the Freederick transition.
Claim 10
Dependent Claim
12 words
The method of claim 1 wherein said electro-optic medium comprises ferroelectric ceramics.
Claim 11
Dependent Claim
14 words
The method of claim 1 wherein said electro-optic medium comprises a ferroelectric single crystal.
Claim 12
Dependent Claim
13 words
The method of claim 1 wherein said electro-optic medium comprises a Pockels crystal.
Claim 13
Dependent Claim
18 words
The method of claim 1 further including a dielectric mirror in between said photoconductor and said electro-optic medium.
Claim 14
Dependent Claim
23 words
The method according to claim 1 wherein said photoconductive layer comprises a material selected from the group consisting of selenium and selenium alloys.
Claim 15
Dependent Claim
13 words
The method according to claim 13 wherein said photoconductive layer comprises arsenic triselenide.
Claim 16
Dependent Claim
99 words
An imaging device, comprising: a. between electrodes, a photoconductive layer and an electro-optic medium without an optical blocking layer therebetween; b. means for applying a voltage between said electrodes; c. means for illuminating said device from one side of said photoconductive layer with actinic radiation in imagewise configuration; and d. means for uniformly illuminating said device from the other side of said photoconductive layer with actinic radiation; said photoconductive layer having a thickness and coefficient of absorption for said actinic radiation effective to establish a space charge limited current upon activation of said means for uniformly illuminating said device.
Claim 17
Dependent Claim
99 words
An imaging device, comprising: a. between electrodes, a photoconductive layer and an electro-optic medium without an optical blocking layer therebetween; b. means for applying a voltage between said electrodes; c. means for illuminating said device from one side of said photoconductive layer with actinic radiation in imagewise configuration; and d. means for uniformly illuminating said device from the other side of said photoconductive layer with actinic radiation; said photoconductive layer having a thickness and coefficient of absorption for said actinic radiation effective to establish a space charge limited current upon activation of said means for uniformly illuminating said device.
Claim 18
Dependent Claim
14 words
The device of claim 15 wherein said electro-optic medium comprises a liquid crystalline composition.
Claim 19
Dependent Claim
13 words
The device of claim 16 wherein said liquid crystalline composition comprises a nematic.
Claim 20
Dependent Claim
12 words
The device of claim 17 wherein said nematic is a twisted nematic.
Claim 21
Dependent Claim
20 words
The device of claim 16 wherein said liquid crystalline composition comprises a mixture of cholesteric and nematic liquid crystalline materials.
Claim 22
Dependent Claim
14 words
The device of claim 15 wherein said electro-optic medium comprises a ferroelectric single crystal.
Claim 23
Dependent Claim
14 words
The device of claim 15 wherein said electro-optic medium comprises a ferroelectric single crystal.
Claim 24
Dependent Claim
13 words
The device of claim 15 wherein said electro-optic medium comprises a Pockels crystal.
Claim 25
Dependent Claim
18 words
The device of claim 15 further including a dielectric mirror in between said photoconductor and said electro-optic medium.
Claim 26
Dependent Claim
23 words
The device according to claim 15 wherein said photoconductive layer comprises a material selected from the group consisting of selenium and selenium alloys.
Claim 27
Dependent Claim
13 words
The device according to claim 24 wherein said photoconductive layer comprises arsenic triselenide.
References Cited (Backward Citations)
US3803408A
Cited
US3944332A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-07-25 | 1981-01-24 | 1981-07-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-07-25 | 1985-01-24 | 1985-07-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-07-25 | 1989-01-24 | 1989-07-26 | $7700.00 | Window Closed / Lapsed |