US3401233A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Focusing in optical systems
Assignee: Redifon Air Trainers Ltd
•
Filing: 1964-11-27
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Granted: 1968-09-10
•
Expires: 1984-11-27
Abstract
No abstract record available.
Inventors
- 👤 Geoffrey M Hellings
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 05:18
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/40
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1971-09-10 | 1972-03-11 | 1972-09-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-09-10 | 1976-03-11 | 1976-09-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-09-10 | 1980-03-11 | 1980-09-10 | $7700.00 | Window Closed / Lapsed |