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US2540835A
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US
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Cathode-ray device
Assignee: AT&T Inc
•
Filing: 1949-12-31
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Granted: 1951-02-06
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Expires: 1969-12-31
Abstract
No abstract record available.
Inventors
- 👤 Anderson Alva Eugene
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:53
CPC Classifications
H; H01; H01J; H01J31/00; H01J31/02; H01J31/04; H01J31/06
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2053268A
Cited
US2200745A
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US2266671A
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US2412965A
Cited
US2328259A
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US2387018A
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US2365476A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-02-05 | 1954-08-07 | 1955-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-02-05 | 1958-08-07 | 1959-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-02-05 | 1962-08-07 | 1963-02-06 | $7700.00 | Window Closed / Lapsed |