US3612656A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Liquid crystal device with lower means located behind the liquid crystal cell
Assignee: AT&T Inc
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Filing: 1969-06-23
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Granted: 1971-10-12
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Expires: 1989-06-23
Abstract
Abstract A display device comprises a pair of transparent substrates sandwiching therebetween a liquid crystal material which is reversibly switchable between transparent and forward-lightscattering states. Disposed behind the device, between it and a source of illumination, is a louver means comprising a plurality of elongated vanes of a dull black, light-absorbent color. The louver is so disposed relative to a viewer of the device and the source of illumination as to provide a continuous, black background for the device.
Inventors
- 👤 Juan R Maldonado
- 👤 Allen H Meitzler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:55
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/03; G02F1/055; H; H01; H01G; H01G7/00; H01G7/02; H01G7/025; H01G7/026
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
46 words
A display device as in claim 1 wherein said louver means comprises a plurality of elongated vanes projecting outwardly from said cell rear surface, said vanes being of a nonreflective, light-absorbent color, and presenting, when viewed along said directions, a continuous dark background for said device.
References Cited (Backward Citations)
US3401267A
Cited
US3499112A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-10-11 | 1975-04-12 | 1975-10-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-10-11 | 1979-04-12 | 1979-10-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-10-11 | 1983-04-12 | 1983-10-12 | $7700.00 | Window Closed / Lapsed |