Patent US2589421A successfully refreshed from Google Patents.
US2589421A
Expired / Lapsed
US
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Luminous flux modulator
Assignee: Individual
•
Filing: 1946-07-03
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Granted: 1952-03-18
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Expires: 1966-07-03
Abstract
No abstract record available.
Inventors
- 👤 Morrison Montford
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 23:33
CPC Classifications
H; H04; H04B; H04B10/00; H04B10/50; H03; H03B; H03B17/00; H04J; H04J1/00; H04J1/02; H04J1/06
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1213147A
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US1548260A
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US1593619A
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US2014741A
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US2031764A
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US2169842A
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US2193875A
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US2380666A
Cited
US2370985A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-03-18 | 1955-09-17 | 1956-03-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-03-18 | 1959-09-17 | 1960-03-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-03-18 | 1963-09-17 | 1964-03-18 | $7700.00 | Window Closed / Lapsed |