US2637243A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Variable phase contrast microscope
Assignee: Ernst Leitz Wetzlar GmbH
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Filing: 1949-04-26
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Granted: 1953-05-05
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Expires: 1969-04-26
Abstract
No abstract record available.
Inventors
- 👤 Marx Helmut
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:26
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)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-05-04 | 1956-11-03 | 1957-05-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-05-04 | 1960-11-03 | 1961-05-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-05-04 | 1964-11-03 | 1965-05-05 | $7700.00 | Window Closed / Lapsed |