Patent US3558213A successfully refreshed from Google Patents.
US3558213A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical frequency filters using disc cavity
Assignee: AT&T Inc
•
Filing: 1969-04-25
•
Granted: 1971-01-26
•
Expires: 1989-04-25
Abstract
Abstract THIS APPLICATION DESCRIBES A VARIETY OF CIRCUIT COMPONENTS FOR USE AT OPTICAL FREQUENCIES. EACH OF THE COMPONENTS IS FORMED FROM ONE OR MORE TRANSPARENT DIELECTRIC STRIPS EMBEDDED IN A TRANSPARENT SUBSTRATE OF SLIGHTLY LOWER REFRACTIVE INDEX. BY SUITABLY SHAPING AND LOCATING THE GUIDING STRIPS, MODULATORS, DIRECTIONAL COUPLERS, AND A VARIETY OF FILTERS CAN BE REALIZED. TUNING ARRANGEMENTS ARE ALSO DISCLOSED.
Inventors
- 👤 Enrique A J Marcatili
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:58
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/24; G02B6/26; G02B6/28; G02B6/293; G02B6/29331; G02B6/29335; G02B6/29338; G02B6/2804; G02B6/2821; G02F; G02F1/00; G02F1/01; G02F1/011; G02F1/03; G02F1/035; H; H01; H01P; H01P1/00; H01P1/20; H01P1/213; G02F2203/00; G02F2203/05; G02F2203/055
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1974-01-25 | 1974-07-27 | 1975-01-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-01-25 | 1978-07-27 | 1979-01-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-01-25 | 1982-07-27 | 1983-01-26 | $7700.00 | Window Closed / Lapsed |