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Patent US2644361A successfully refreshed from Google Patents.
US2644361A
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Projection plotting lens and optical system
Assignee: United States Department of the Navy
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Filing: 1946-09-30
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Granted: 1953-07-07
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Expires: 1966-09-30
Abstract
No abstract record available.
Inventors
- 👤 Edwin H Birdsall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 15:24
CPC Classifications
G; G02; G02B; G02B3/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-07-06 | 1957-01-05 | 1957-07-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-07-06 | 1961-01-05 | 1961-07-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-07-06 | 1965-01-05 | 1965-07-07 | $7700.00 | Window Closed / Lapsed |