US2663223A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Variable magnification optical system
Assignee: W Watson and Sons Ltd
•
Filing: 1951-07-13
•
Granted: 1953-12-22
•
Expires: 1971-07-13
Abstract
No abstract record available.
Inventors
- 👤 Hopkins Harold Horace
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 07:12
CPC Classifications
G; G02; G02B; G02B15/00; G02B15/14; G02B15/145; G02B15/1451; G02B15/145125
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1790232A
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US1947669A
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US2235364A
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US2159394A
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US2165341A
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US2353565A
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US2501219A
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US2514239A
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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) | 1956-12-21 | 1957-06-22 | 1957-12-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-12-21 | 1961-06-22 | 1961-12-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-12-21 | 1965-06-22 | 1965-12-22 | $7700.00 | Window Closed / Lapsed |