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US2679183A
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Differential interferometer
Assignee: Individual
•
Filing: 1950-10-10
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Granted: 1954-05-25
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Expires: 1970-10-10
Abstract
No abstract record available.
Inventors
- 👤 Donald R Buchele
- 👤 Pierce B Day
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 11:00
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/17; G01N21/41; G01N21/45
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
DE509310C
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DE499545C
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DE577377C
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GB386315A
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US2256804A
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US2256855A
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FR883076A
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US2434029A
Cited
US2483244A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-05-24 | 1957-11-23 | 1958-05-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-05-24 | 1961-11-23 | 1962-05-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-05-24 | 1965-11-23 | 1966-05-25 | $7700.00 | Window Closed / Lapsed |