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US2644938A
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Schlieren cathode-ray light modulator with modulating liquid on concave mirror
Assignee: Gesellschaft zur Foerderung der Forschung an der Eidgenoessischen Technischen Hochschule
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Filing: 1949-03-05
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Granted: 1953-07-07
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Expires: 1969-03-05
Abstract
No abstract record available.
Inventors
- 👤 Hetzel Max
- 👤 Mast Fred August
- 👤 Thiemann Hugo Ernst Wilhelm
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:27
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/74; H04N5/7416; H04N5/7425
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2276360A
Cited
US2391451A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-07-06 | 1957-01-05 | 1957-07-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-07-06 | 1961-01-05 | 1961-07-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-07-06 | 1965-01-05 | 1965-07-07 | $7700.00 | Window Closed / Lapsed |