Patent US1658489A successfully refreshed from Google Patents.
Patent US1769920A successfully refreshed from Google Patents.
US1769920A
Expired / Lapsed
US
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Electrooptical transmission system
Assignee: AT&T Inc
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Filing: 1929-04-30
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Granted: 1930-07-08
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Expires: 1949-04-30
Abstract
No abstract record available.
Inventors
- 👤 Gray Frank
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 03:35
CPC Classifications
H; H04; H04J; H04J1/00; H04N; H04N5/00; H04N5/14; H04N5/16; H04N7/00; H04N7/08; H04N7/0803; H04N7/12; H04N7/127
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) | 1933-07-07 | 1934-01-06 | 1934-07-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1937-07-07 | 1938-01-06 | 1938-07-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1941-07-07 | 1942-01-06 | 1942-07-08 | $7700.00 | Window Closed / Lapsed |