US3491237A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical structures
Assignee: DEPARTAMENTO DE BIOLOG CENTRO
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Filing: 1967-08-09
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Granted: 1970-01-20
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Expires: 1987-08-09
Abstract
No abstract record available.
Inventors
- 👤 Stephen S Tillett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 14:05
CPC Classifications
F; F21; F21K; F21K2/00; G; G02; G02B; G02B1/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2379741A
Cited
US2485561A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-01-19 | 1973-07-21 | 1974-01-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-01-19 | 1977-07-21 | 1978-01-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-01-19 | 1981-07-21 | 1982-01-20 | $7700.00 | Window Closed / Lapsed |