Patent US2683394A successfully refreshed from Google Patents.
US2683394A
Expired / Lapsed
US
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Wide aperture optical projection lens system
Assignee: American Optical Corp
•
Filing: 1951-09-08
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Granted: 1954-07-13
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Expires: 1971-09-08
Abstract
No abstract record available.
Inventors
- 👤 Michael L Polanyi
- 👤 Osterberg Harold
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 23:52
CPC Classifications
G; G02; G02B; G02B17/00; G02B17/08; G02B17/0856; G02B17/086; G02B17/0804; G02B17/0808; G02B17/0884; G02B17/0888; G02B17/0896
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1390445A
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US2336379A
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US2295802A
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US2336134A
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US2378301A
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US2454144A
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US2477331A
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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) | 1957-07-12 | 1958-01-11 | 1958-07-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-07-12 | 1962-01-11 | 1962-07-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-07-12 | 1966-01-11 | 1966-07-13 | $7700.00 | Window Closed / Lapsed |