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Patent US2516905A successfully refreshed from Google Patents.
US2516905A
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Microscope with variable polarizing and birefringent means for producing contrast inoptical images
Assignee: American Optical Corp
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Filing: 1946-07-02
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Granted: 1950-08-01
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Expires: 1966-07-02
Abstract
No abstract record available.
Inventors
- 👤 Osterberg Harold
- 👤 Alva H Bennett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:31
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)
DE636168C
Cited
US2105671A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-07-31 | 1954-01-30 | 1954-08-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-07-31 | 1958-01-30 | 1958-08-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-07-31 | 1962-01-30 | 1962-08-01 | $7700.00 | Window Closed / Lapsed |