Patent US2464419A successfully refreshed from Google Patents.
US2464419A
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US
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Method of and apparatus for selectively achieving electronic darkfield and bright field illumation
Assignee: RCA Corp
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Filing: 1947-12-26
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Granted: 1949-03-15
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Expires: 1967-12-26
Abstract
No abstract record available.
Inventors
- 👤 Perry C Smith
- 👤 John H Reisner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 14:57
CPC Classifications
H; H01; H01J; H01J37/00; H01J37/26; H01J37/261; H01J37/265
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1952-03-14 | 1952-09-13 | 1953-03-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-03-14 | 1956-09-13 | 1957-03-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-03-14 | 1960-09-13 | 1961-03-15 | $7700.00 | Window Closed / Lapsed |