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US3497757A
Expired / Lapsed
US
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Tungsten dispenser cathode having emission enhancing coating of osmium-iridium or osmium-ruthenium alloy for use in electron tube
Assignee: US Philips Corp
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Filing: 1968-05-29
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Granted: 1970-02-24
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Expires: 1988-05-29
Abstract
No abstract record available.
Inventors
- 👤 Pieter Zalm
- 👤 Antonius Johannes Albe Stratum
- 👤 Henricus Hubertus Peeters
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 16:27
CPC Classifications
H; H01; H01J; H01J1/00; H01J1/02; H01J1/13; H01J1/20; H01J1/28; H01J1/14
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) | 1973-02-23 | 1973-08-25 | 1974-02-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-02-23 | 1977-08-25 | 1978-02-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-02-23 | 1981-08-25 | 1982-02-24 | $7700.00 | Window Closed / Lapsed |