US2669709A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Image projection optical system
Assignee: American Optical Corp
•
Filing: 1950-10-19
•
Granted: 1954-02-16
•
Expires: 1970-10-19
Abstract
No abstract record available.
Inventors
- 👤 Anna E Glancy
- 👤 John K Davis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 17:45
CPC Classifications
G; G02; G02B; G02B17/00; G02B17/08; G02B17/0884; G02B17/0888
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2170979A
Cited
US2141884A
Cited
US2273801A
Cited
US2309788A
Cited
GB544694A
Cited
US2510521A
Cited
US2518067A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-02-15 | 1957-08-17 | 1958-02-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-02-15 | 1961-08-17 | 1962-02-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-02-15 | 1965-08-17 | 1966-02-16 | $7700.00 | Window Closed / Lapsed |