US2514239A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Variable magnification optical system
Assignee: W Watson and Sons Ltd
•
Filing: 1948-10-22
•
Granted: 1950-07-04
•
Expires: 1968-10-22
Abstract
No abstract record available.
Inventors
- 👤 Hopkins Harold Horace
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 01:43
CPC Classifications
G; G02; G02B; G02B15/00; G02B15/14; G02B15/144; G02B15/1441; G02B15/144109
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US696788A
Cited
GB190121211A
Cited
GB191203799A
Cited
US1709232A
Cited
US2165341A
Cited
US2405729A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-07-03 | 1954-01-02 | 1954-07-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-07-03 | 1958-01-02 | 1958-07-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-07-03 | 1962-01-02 | 1962-07-04 | $7700.00 | Window Closed / Lapsed |