Patent US2302081A successfully refreshed from Google Patents.
US2989895A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical objective
Assignee: Bell and Howell Co
•
Filing: 1958-06-30
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Granted: 1961-06-27
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Expires: 1978-06-30
Abstract
No abstract record available.
Inventors
- 👤 Irving C Sandback
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:56
CPC Classifications
G; G02; G02B; G02B13/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1996054A
Cited
US2076190A
Cited
US2384624A
Cited
GB593514A
Cited
GB673353A
Cited
DE891469C
Cited
US2604013A
Cited
GB714550A
Cited
US2833181A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-06-26 | 1964-12-26 | 1965-06-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-06-26 | 1968-12-26 | 1969-06-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-06-26 | 1972-12-26 | 1973-06-27 | $7700.00 | Window Closed / Lapsed |