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US2587451A
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Slit control for spectroscopic apparatus
Assignee: Farrand Optical Co Inc
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Filing: 1949-03-01
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Granted: 1952-02-26
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Expires: 1969-03-01
Abstract
No abstract record available.
Inventors
- 👤 Clair L Farrand
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:59
CPC Classifications
G; G01; G01J; G01J3/00; G01J3/02; G01J3/04; Y; Y10; Y10T; Y10T74/00; Y10T74/18; Y10T74/18056; Y10T74/1828
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1964365A
Cited
GB503167A
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US2227510A
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US2236379A
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US2411741A
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US2408512A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-02-25 | 1955-08-27 | 1956-02-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-02-25 | 1959-08-27 | 1960-02-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-02-25 | 1963-08-27 | 1964-02-26 | $7700.00 | Window Closed / Lapsed |