US2437774A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Direct reading photoelectric exposure meter
Assignee: Individual
•
Filing: 1944-12-16
•
Granted: 1948-03-16
•
Expires: 1964-12-16
Abstract
No abstract record available.
Inventors
- 👤 Frederick P Willcox
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 09:22
CPC Classifications
G; G01; G01J; G01J1/00; G01J1/42; G01J1/4209; G01J1/4214
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1144142A
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US1895271A
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US2070664A
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US2048655A
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US2091464A
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GB458546A
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US2199464A
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US2178197A
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US2287430A
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US2268105A
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US2387466A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1951-03-16 | 1951-09-15 | 1952-03-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1955-03-16 | 1955-09-15 | 1956-03-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1959-03-16 | 1959-09-15 | 1960-03-16 | $7700.00 | Window Closed / Lapsed |