US2846923A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High speed objective lens with anastigmatically flattened field
Assignee: Farrand Optical Co Inc
•
Filing: 1957-02-25
•
Granted: 1958-08-12
•
Expires: 1977-02-25
Abstract
No abstract record available.
Inventors
- 👤 Tronnier Albrecht Wilhelm
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 06:42
CPC Classifications
G; G02; G02B; G02B13/00; G02B13/16
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1812717A
Cited
US2012822A
Cited
GB439142A
Cited
US2319171A
Cited
US2586866A
Cited
US2662447A
Cited
US2677989A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-08-11 | 1962-02-10 | 1962-08-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-08-11 | 1966-02-10 | 1966-08-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-08-11 | 1970-02-10 | 1970-08-12 | $7700.00 | Window Closed / Lapsed |