US3560874A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Variable optical frequency shifter
Assignee: AT&T Inc
•
Filing: 1966-10-12
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Granted: 1971-02-02
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Expires: 1986-10-12
Abstract
Abstract THE OPTICAL FREQUENCY OF A COHERENT OPTICAL PULSE TRAIN IS SHIFTED BY MEANS OF AN ELECTRO-OPTIC CRYSTAL TO WHICH IS APPLIED A SINUSOIDAL ELECTRIC FIELD SYNCHRONIZED IN FREQUENCY (WITH THE PULSE REPETITION RATE) AND PHASE WITH THE PULSE TRAIN. THE PHASE IS ADJUSTED SUCH THAT REFRACTION INDEX OF THE CRYSTAL IS CHANGING AT ITS FASTEST RATE WHEN A PULSE TRANSVERSES THE CRYSTAL. THE CHANGE IN INDEX OF REFRACTION OF THE CRYSTAL IS DIRECTLY PROPORTIONAL TO THE MAGNITUDE OF THE APPLIED ELECTRIC FIELD, HENCE THE TOTAL FREQUENCY SHIFT IS GOVERNED BY THE NUMBER OF REFLECTIONS AND THE APPLIED FIELD, THE MAGNITUDE OF WHICH IS MADE CONTROLLABLE.
Inventors
- 👤 Michel A Duguay
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 20:03
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/03; G02F1/0327
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-02-01 | 1974-08-03 | 1975-02-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-02-01 | 1978-08-03 | 1979-02-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-02-01 | 1982-08-03 | 1983-02-02 | $7700.00 | Window Closed / Lapsed |