Patent US3290543A successfully refreshed from Google Patents.
US3290543A
Expired / Lapsed
US
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Grain oriented dispenser thermionic emitter for electron discharge device
Assignee: Varian Medical Systems Inc
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Filing: 1964-05-13
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Granted: 1966-12-06
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Expires: 1984-05-13
Abstract
No abstract record available.
Inventors
- 👤 Weissman Ira
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 11:53
CPC Classifications
H; H01; H01J; H01J1/00; H01J1/02; H01J1/13; H01J1/20; H01J1/28; H01J1/14; H01J3/00; H01J3/02; H01J45/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
107 words
A THERMIONIC EMITTER STRUCTURE ADAPTED FOR OPERATION AT ELEVATED TEMPERATURES FOR EMITTING A STREAM OF ELECTRONS, SAID EMITTER STRUCTURE HAVING AN EMITTING SURFACE FOR EMITTING THE STREAM OF ELECTRONS AND BEING FORMED BY A LAYER OF GRAIN ORIENTED POLYCRYSTALLINE MATERIAL, MEANS FORMING A SOURCE SUPPLYING A LAYER OF COATING MATERIAL TO SAID POLYCRYSTALLINE EMITTING SURFACE, SAID LAYER OF MATERIAL HAVING A LOWER WORK FUNCTION THAN THE BARE EMITTING SURFACE WHEREBY THE WORK FUNCTION OF SAID COATED SURFACE IS LOWERED UNIFORMLY, AND SAID LAYER OF LOW WORK FUNCTION MATERIAL BEING DEPLETED IN USE AND BEING REPLENISHED IN USE BY DIFFUSION FROM SAID SOURCE THROUGH SAID POLYCRYSTALLINE EMITTING SURFACE.
Claim 2
Dependent Claim
107 words
A THERMIONIC EMITTER STRUCTURE ADAPTED FOR OPERATION AT ELEVATED TEMPERATURES FOR EMITTING A STREAM OF ELECTRONS, SAID EMITTER STRUCTURE HAVING AN EMITTING SURFACE FOR EMITTING THE STREAM OF ELECTRONS AND BEING FORMED BY A LAYER OF GRAIN ORIENTED POLYCRYSTALLINE MATERIAL, MEANS FORMING A SOURCE SUPPLYING A LAYER OF COATING MATERIAL TO SAID POLYCRYSTALLINE EMITTING SURFACE, SAID LAYER OF MATERIAL HAVING A LOWER WORK FUNCTION THAN THE BARE EMITTING SURFACE WHEREBY THE WORK FUNCTION OF SAID COATED SURFACE IS LOWERED UNIFORMLY, AND SAID LAYER OF LOW WORK FUNCTION MATERIAL BEING DEPLETED IN USE AND BEING REPLENISHED IN USE BY DIFFUSION FROM SAID SOURCE THROUGH SAID POLYCRYSTALLINE EMITTING SURFACE.
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) | 1969-12-05 | 1970-06-06 | 1970-12-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-12-05 | 1974-06-06 | 1974-12-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-12-05 | 1978-06-06 | 1978-12-06 | $7700.00 | Window Closed / Lapsed |