Patent US2287587A successfully refreshed from Google Patents.
US2287587A
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Light modulating apparatus
Assignee: AT&T Inc
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Filing: 1939-11-02
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Granted: 1942-06-23
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Expires: 1959-11-02
Abstract
No abstract record available.
Inventors
- 👤 Gerald W Willard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 23:33
CPC Classifications
H; H04; H04B; H04B10/00; H04B10/50; F; F21; F21V; F21V21/00; F21V21/14; F21V21/26; G; G02; G02F; G02F1/00; G02F1/01; G02F1/11
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) | 1945-06-22 | 1945-12-22 | 1946-06-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1949-06-22 | 1949-12-22 | 1950-06-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1953-06-22 | 1953-12-22 | 1954-06-23 | $7700.00 | Window Closed / Lapsed |