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US2660915A
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Interference-schlieren apparatus
Assignee: Individual
•
Filing: 1950-07-25
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Granted: 1953-12-01
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Expires: 1970-07-25
Abstract
No abstract record available.
Inventors
- 👤 Theodor W Zobel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 08:32
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/50; G02B27/54
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) | 1956-11-30 | 1957-06-01 | 1957-12-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-11-30 | 1961-06-01 | 1961-12-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-11-30 | 1965-06-01 | 1965-12-01 | $7700.00 | Window Closed / Lapsed |