Patent US2680148A successfully refreshed from Google Patents.
Patent US2471249A successfully refreshed from Google Patents.
US2471249A
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Photometric apparatus and spectrophotometer using polarized light and a multiple retardation plate
Assignee: Wyeth Holdings LLC
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Filing: 1944-12-27
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Granted: 1949-05-24
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Expires: 1964-12-27
Abstract
No abstract record available.
Inventors
- 👤 Jr Edwin I Stearns
- 👤 George L Buc
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 05:25
CPC Classifications
G; G01; G01J; G01J3/00; G01J3/02; G01J1/00; G01J1/02; G01J1/04; G01J1/0407; G01J1/0414; G01J1/0418; G01J1/0474; G01J1/10; G01J1/20; G01J1/34; G01J1/36; G01J3/0205; G01J3/021; G01J3/0224; G01J3/0229; G01J3/0237; G01J3/12; G01J3/14; G01J2001/0481
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
DE587850C
Cited
US2189270A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1952-05-23 | 1952-11-22 | 1953-05-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-05-23 | 1956-11-22 | 1957-05-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-05-23 | 1960-11-22 | 1961-05-24 | $7700.00 | Window Closed / Lapsed |