US2746348A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical viewing device with contrasting color phases
Assignee: Ernst Leitz Wetzlar GmbH
•
Filing: 1951-09-12
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Granted: 1956-05-22
•
Expires: 1971-09-12
Abstract
No abstract record available.
Inventors
- 👤 Leitz Ludwig
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 15:03
CPC Classifications
G; G02; G02B; G02B21/00; G02B21/06; G02B21/08; G02B21/14
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2675737A
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US2083820A
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US2427689A
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US2519428A
Cited
US2616334A
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US2594757A
Cited
GB648801A
Cited
US2674157A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-05-22 | 1959-11-21 | 1960-05-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-05-22 | 1963-11-21 | 1964-05-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-05-22 | 1967-11-21 | 1968-05-22 | $7700.00 | Window Closed / Lapsed |