Patent US3792259A successfully refreshed from Google Patents.
US3792259A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electro-optic device comprising an optic image relay and method of manufacturing same
Assignee: US Philips Corp
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Filing: 1972-03-28
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Granted: 1974-02-12
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Expires: 1992-03-28
Abstract
Abstract An electro-optical device including a writing beam, a reading beam and an optic relay comprising a plate of a material having double refraction. According to the invention, a direct voltage is applied between the faces of the plate, the information being written by modulation of the writing beam. Application in information processing, display of data and the projection of images.
Inventors
- 👤 J Donjon
- 👤 J Hazan
- 👤 G Marie
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 16:25
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/03; G02F1/0333; G02F1/0338
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
107 words
A method of algebraically adding images in an optic image relay of the type wherein an image pattern optically projected on a photosensitive layer by a first source of light radiation is converted thereby into an electrical pattern on an electrically biassed electro-optic plate interrogated by a second source of radiation, comprising the steps of first projecting an image pattern on the photosensitive layer with the radiation level of the first source of light radiation and the electrical bias level on the electro-optic plate having intensities sufficient to produce a partially induced double refraction in the electrooptic plate, and repeating the first step a plurality of times.
Claim 2
Independent Claim
107 words
A method of algebraically adding images in an optic image relay of the type wherein an image pattern optically projected on a photosensitive layer by a first source of light radiation is converted thereby into an electrical pattern on an electrically biassed electro-optic plate interrogated by a second source of radiation, comprising the steps of first projecting an image pattern on the photosensitive layer with the radiation level of the first source of light radiation and the electrical bias level on the electro-optic plate having intensities sufficient to produce a partially induced double refraction in the electrooptic plate, and repeating the first step a plurality of times.
Claim 3
Dependent Claim
54 words
A method as claimed in claim 1, further comprising the step of reversing the electrical bias level on the electro-optic plate and then exposing the photosensitive layer to a plurality of second image patterns whereby the induced double refraction in the electro-optic plate corresponds to the difference between the first and second image pattern.
Claim 4
Dependent Claim
63 words
A method as claimed in claim 2, wherein the first pattern on the photosensitive layer is spatially unmodulated during one of the two writing sequencies at a value corresponding to an induced double refraction equal, in absolute value, to the maximum double refraction induced at the brightest point during the other sequence, whereby the negative image corresponding to said other sequence is produced.
Claim 5
Dependent Claim
85 words
A method as claimed in claim 2, wherein the first pattern on the photosensitive layer is spatially unmodulated during one of the two writing sequencies at a value corresponding to an induced double refraction equal, in absolute value, to the induced average double refraction during the other sequence, whereby a zero average transmission, in amplitude, of the second light radiation is obtained and the zero order of diffraction in the Fourier transform of the image which may be Formed with said second radiation is eliminated.
References Cited (Backward Citations)
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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) | 1977-02-11 | 1977-08-13 | 1978-02-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-11 | 1981-08-13 | 1982-02-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-11 | 1985-08-13 | 1986-02-12 | $7700.00 | Window Closed / Lapsed |