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US2541437A
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US
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Apparatus for investigating optical refraction phenomena in gaseous media
Assignee: Individual
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Filing: 1948-07-30
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Granted: 1951-02-13
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Expires: 1968-07-30
Abstract
No abstract record available.
Inventors
- 👤 Prescott Rochelle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 10:40
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/50; G02B27/54; G01; G01N; G01N21/00; G01N21/17; G01N21/41; G01N21/45
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-02-12 | 1954-08-14 | 1955-02-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-02-12 | 1958-08-14 | 1959-02-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-02-12 | 1962-08-14 | 1963-02-13 | $7700.00 | Window Closed / Lapsed |