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US3720658A
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Cholesteryl p-phenylazophenyl carbonate
Assignee: Westinghouse Electric Corp
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Filing: 1971-08-09
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Granted: 1973-03-13
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Expires: 1991-08-09
Abstract
Abstract Electromagnetic radiation in the frequency range of about 1015 to 1017 cycles per second is detected, using a cholesteric liquid-crystal material to which there has been added cholesteryl p-phenylazophenyl carbonate, a novel compound.
Inventors
- 👤 N Goldberg
- 👤 J Fergason
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 03:55
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/132; G03; G03C; G03C1/00; G03C1/72; G03C1/73
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US3114836A
Cited
US3401262A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-03-12 | 1976-09-11 | 1977-03-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-12 | 1980-09-11 | 1981-03-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-12 | 1984-09-11 | 1985-03-13 | $7700.00 | Window Closed / Lapsed |