US3307974A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of forming thermionic cathodes
Assignee: Rank Radio and Television Ltd
•
Filing: 1963-02-08
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Granted: 1967-03-07
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Expires: 1983-02-08
Abstract
No abstract record available.
Inventors
- 👤 Davis Edwin John
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 15:40
CPC Classifications
H; H01; H01J; H01J9/00; H01J9/02; H01J9/04
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
66 words
A METHOD OF FORMING A THERMINOIC CATHODE ON AN INSULATING BODY COMPRISING IN THE ORDER NAMED THE STEPS OF: DEPOSITING A FIRST LAYER OF CONDUCTIVE MATERIAL ONTO SAID BODY TO FORM A HEATER FOR THE CATHODE; COATING SAID HEATER AT LEAST IN PART WITH A LAYER OF INSULATING MATEIAL; AND DEPOSITING A LAYER OF ELECTRON EMISSIVE MATERIAL ON AT LEAST A PORTION OF SAID INSULATING LAYER.
Claim 2
Independent Claim
66 words
A METHOD OF FORMING A THERMINOIC CATHODE ON AN INSULATING BODY COMPRISING IN THE ORDER NAMED THE STEPS OF: DEPOSITING A FIRST LAYER OF CONDUCTIVE MATERIAL ONTO SAID BODY TO FORM A HEATER FOR THE CATHODE; COATING SAID HEATER AT LEAST IN PART WITH A LAYER OF INSULATING MATEIAL; AND DEPOSITING A LAYER OF ELECTRON EMISSIVE MATERIAL ON AT LEAST A PORTION OF SAID INSULATING LAYER.
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) | 1970-03-06 | 1970-09-05 | 1971-03-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-03-06 | 1974-09-05 | 1975-03-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-03-06 | 1978-09-05 | 1979-03-07 | $7700.00 | Window Closed / Lapsed |