Patent US2495708A successfully refreshed from Google Patents.
US2495708A
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Electrically controlled flicker fusion testing apparatus
Assignee: Individual
•
Filing: 1944-03-24
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Granted: 1950-01-31
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Expires: 1964-03-24
Abstract
No abstract record available.
Inventors
- 👤 Rupert H Draeger
- 👤 Friedman Herbert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 14:30
CPC Classifications
H; H05; H05B; H05B39/00; H05B39/09; A; A61; A61B; A61B5/00; A61B5/16; A61B5/161; A61B5/18
Claims Analysis
Total Claims: 0
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-01-30 | 1953-08-01 | 1954-01-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-01-30 | 1957-08-01 | 1958-01-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-01-30 | 1961-08-01 | 1962-01-31 | $7700.00 | Window Closed / Lapsed |