Patent US2822499A successfully refreshed from Google Patents.
US2822499A
Expired / Lapsed
US
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Cathodes for electron discharge devices
Assignee: AT&T Inc
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Filing: 1955-02-17
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Granted: 1958-02-04
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Expires: 1975-02-17
Abstract
No abstract record available.
Inventors
- 👤 Robert T Lynch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 09:23
CPC Classifications
H; H01; H01J; H01J23/00; H01J23/02; H01J23/04; H01J23/05
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-02-03 | 1961-08-05 | 1962-02-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-02-03 | 1965-08-05 | 1966-02-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-02-03 | 1969-08-05 | 1970-02-04 | $7700.00 | Window Closed / Lapsed |