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US2673923A
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Means for producing colored light beams
Assignee: Duro Test Corp
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Filing: 1947-12-03
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Granted: 1954-03-30
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Expires: 1967-12-03
Abstract
No abstract record available.
Inventors
- 👤 Williams Rollo Gillespie
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 17:47
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/10; G02B27/12; G02B27/123; G02B27/1006; G02B27/14; G02B27/143; F; F21; F21W; F21W2121/00; F21W2131/00; F21W2131/40; F21W2131/406
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US961852A
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US1223459A
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US1458826A
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US1601358A
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US1738942A
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US2217790A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-03-29 | 1957-09-28 | 1958-03-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-03-29 | 1961-09-28 | 1962-03-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-03-29 | 1965-09-28 | 1966-03-30 | $7700.00 | Window Closed / Lapsed |