US3596131A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cathode secondary emitter for crossed-field tubes
Assignee: Varian Medical Systems Inc
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Filing: 1969-05-29
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Granted: 1971-07-27
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Expires: 1989-05-29
Abstract
Abstract In a crossed-field tube of the type employing a cathode secondary emitter, the secondary emission surface is corrugated with the corrugations being elongated generally in the direction of the secondary electron stream to increase the effective secondary electron emissive surface area of the cathode and to increase the secondary electron emission yield from the surface, whereby the current loading on the cathode is decreased in use.
Inventors
- 👤 Andrew S Wilczek
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 06:02
CPC Classifications
H; H01; H01J; H01J1/00; H01J1/02; H01J1/32; H01J25/00; H01J25/34; H01J25/42; H01J25/44
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
104 words
In a crossed-field microwave tube, means forming a cathode electrode structure having a secondary emission surface for generating a stream of secondary emitted electrons by electron back-bombardment of said secondary emission surface means forming an anode electrode structure spaced from said cathode electrode to define a crossed-field interaction region therebetween, the improvement wherein, said cathode secondary emission surface includes a multitude of corrugations being elongated generally in the direction of the secondary electron stream, said corrugations being shallow enough that the shape of the electric field in the interaction region is substantially uninfluenced thereby, whereby the secondary electron emission from said cathode is increased.
Claim 2
Dependent Claim
104 words
In a crossed-field microwave tube, means forming a cathode electrode structure having a secondary emission surface for generating a stream of secondary emitted electrons by electron back-bombardment of said secondary emission surface means forming an anode electrode structure spaced from said cathode electrode to define a crossed-field interaction region therebetween, the improvement wherein, said cathode secondary emission surface includes a multitude of corrugations being elongated generally in the direction of the secondary electron stream, said corrugations being shallow enough that the shape of the electric field in the interaction region is substantially uninfluenced thereby, whereby the secondary electron emission from said cathode is increased.
Claim 3
Dependent Claim
18 words
The apparatus of claim 1 wherein the indented portions of the corrugations are of generally triangular cross section.
Claim 4
Dependent Claim
20 words
The apparatus of claim 1 wherein the indented portions of the corrugations have a depth less than their maximum width.
Claim 5
Dependent Claim
26 words
The apparatus of claim 2 wherein the land portions of the corrugations defined between adjacent indented portions of the corrugations are generally of triangular cross section.
Claim 6
Dependent Claim
54 words
The apparatus of claim 1 wherein said anode electrode includes a microwave slow wave circuit portion facing said cathode electrode structure, said slow wave circuit having an input terminal and an output terminal for applying microwave energy to be amplified to said circuit and for extracting the amplified microwave energy from said circuit, respectively.
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) | 1974-07-26 | 1975-01-25 | 1975-07-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-26 | 1979-01-25 | 1979-07-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-26 | 1983-01-25 | 1983-07-27 | $7700.00 | Window Closed / Lapsed |