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Patent US3243640A successfully refreshed from Google Patents.
US3243640A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Space-charge neutralized electron gun
Assignee: RCA Corp
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Filing: 1963-02-08
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Granted: 1966-03-29
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Expires: 1983-02-08
Abstract
No abstract record available.
Inventors
- 👤 Arie L Eichenbaum
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 16:40
CPC Classifications
H; H01; H01J; H01J3/00; H01J3/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
126 words
AN ELECTRON GUN COMPRISING: (A) A PLURALITY OF ELECTRODES INCLUDING (1) A THERMIONIC CATHODE HAVING A RELATIVELY LARGE ELECTRON EMISSIVE SURFACE, AND (2) A BEAM FORMING PLATE ELECTRODE ADJACENT TO SAID CATHODE HAVING A SINGLE APERTURE SPACED FROM SAID SURFACE AND HAVING AN APERTURE AREA THAT IS SMALL COMPARED TO THE AREA OF SAID SURFACE; (B) MEANS, INCLUDING ONE OF SAID ELECTRODES, FOR INTRODUCING POSITIVE IONS INTO THE SPACE BETWEEN SAID SURFACE AND SAID APERTURE OTHER THAN BY IONIZATION BY ELECTRON IMPACT EMITTED BY SAID SURFACE AND THEREBY FORMING A PLASMA IN SAID SPACE; AND (C) MEANS, INCLUDING AN APERTURED POSITIVE ACCELERATING ELECTRODE COAXIALLY POSITIONED ADJACENT TO SAID APERTURED BEAM FORMING ELECTRODE, FOR EXTRACTING A DENSE, SUBSTANTIALLY THERMAL ELECTRON CURRENT FROM SAID PLASMA THROUGH SAID APERTURE.
Claim 2
Dependent Claim
126 words
AN ELECTRON GUN COMPRISING: (A) A PLURALITY OF ELECTRODES INCLUDING (1) A THERMIONIC CATHODE HAVING A RELATIVELY LARGE ELECTRON EMISSIVE SURFACE, AND (2) A BEAM FORMING PLATE ELECTRODE ADJACENT TO SAID CATHODE HAVING A SINGLE APERTURE SPACED FROM SAID SURFACE AND HAVING AN APERTURE AREA THAT IS SMALL COMPARED TO THE AREA OF SAID SURFACE; (B) MEANS, INCLUDING ONE OF SAID ELECTRODES, FOR INTRODUCING POSITIVE IONS INTO THE SPACE BETWEEN SAID SURFACE AND SAID APERTURE OTHER THAN BY IONIZATION BY ELECTRON IMPACT EMITTED BY SAID SURFACE AND THEREBY FORMING A PLASMA IN SAID SPACE; AND (C) MEANS, INCLUDING AN APERTURED POSITIVE ACCELERATING ELECTRODE COAXIALLY POSITIONED ADJACENT TO SAID APERTURED BEAM FORMING ELECTRODE, FOR EXTRACTING A DENSE, SUBSTANTIALLY THERMAL ELECTRON CURRENT FROM SAID PLASMA THROUGH SAID APERTURE.
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) | 1969-03-28 | 1969-09-27 | 1970-03-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-03-28 | 1973-09-27 | 1974-03-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-03-28 | 1977-09-27 | 1978-03-29 | $7700.00 | Window Closed / Lapsed |