US2811081A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Universal focal length photo-objective system
Assignee: Individual
•
Filing: 1952-07-03
•
Granted: 1957-10-29
•
Expires: 1972-07-03
Abstract
No abstract record available.
Inventors
- 👤 Henry L Praeger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 07:46
CPC Classifications
G; G02; G02B; G02B15/00; G02B15/02; G02B5/00; G02B5/001
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US494128A
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US1143316A
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US1154232A
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US1351785A
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GB335696A
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US2109474A
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US2101016A
Cited
US2233591A
Cited
US2475275A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-10-28 | 1961-04-29 | 1961-10-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-10-28 | 1965-04-29 | 1965-10-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-10-28 | 1969-04-29 | 1969-10-29 | $7700.00 | Window Closed / Lapsed |