US3745402A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Field effect electron emitter
Assignee: Individual
•
Filing: 1971-12-17
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Granted: 1973-07-10
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Expires: 1991-12-17
Abstract
Abstract A unique electron source comprises an oxide-metal composite capable of emitting electrons at ambient temperatures when subjected to an electric field. The quantity of electrons emitted depends on the electric field provided for the emitter and thermionic emission is not employed during any stage of emission. The electron source, a field effect emitter, can have more than a million metal fibers for each square centimeter of emitter surface area. The metal fibers are normally less than one micron in diameter and are uniformly embedded within an oxide insulator for emitting electrons from the ends of the metal fibers.
Inventors
- 👤 J Shelton
- 👤 J Hagood
- 👤 R Norman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 22:22
CPC Classifications
H; H01; H01J; H01J1/00; H01J1/02; H01J1/30; H01J1/304; H01J1/3042; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24479; Y10T428/24612; Y10T428/249921; Y10T428/249924; Y10T428/249928
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
27 words
An ambient temperature cathode as set forth in claim 1 and further comprising an insulating filler encompassing said conductive rods for insulating each rod from adjacent rods.
Claim 2
Dependent Claim
34 words
A cathode as set forth in claim 2 wherein said rods are tungsten said filler is a uranium oxide matrix, and said metal rods terminate in a plane forming the surface of said matrix.
Claim 3
Dependent Claim
103 words
A field effect electron emitter for use in electron tubes comprising: a plurality of parallel metal fibers, an insulating oxide matrix incompassing and supporting said fibers, a conductive backing plate in common with a first end of each of said fibers for supplying an electrical potential thereto, the other ends of said fibers forming a plane for emitting electrons therefrom at prevailing ambient temperatures, and approximately one million parallel fibers for each square centimeter of emitter surface, said fibers having a diameter less than one micron and being evenly spaced apart for providing a uniform electric field across the equal potential surface thereof.
Claim 4
Dependent Claim
28 words
An electron emitter as set forth in clAim 4 wherein said metal fibers extend a uniform distance beyond the surface of said oxide for enchancing electron field emission.
Claim 5
Dependent Claim
29 words
An electron emitter as set forth in claim 4 wherein said fibers are recessed a uniform distance below the surface of said oxide and said oxide is uranium oxide.
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) | 1976-07-09 | 1977-01-08 | 1977-07-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-09 | 1981-01-08 | 1981-07-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-09 | 1985-01-08 | 1985-07-10 | $7700.00 | Window Closed / Lapsed |