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US3746905A Expired / Lapsed US ⏱️ 0.0 years remaining

High vacuum, field effect electron tube

Assignee: United States Department of the Army
•
Filing: 1971-12-21
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Granted: 1973-07-17
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Expires: 1991-12-21
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Abstract

Abstract An improved electron tube is provided which eliminates the need for a heated electron source and affords simplified construction. The tube, a high vacuum tube, is capable of operating over an extended range of electrical potentials. The electron tube operates on the principle of electric field effect emission for the electron source, requiring neither gas, vapor nor a heated electrode in its envelope. Two active elements, an emitter and a collector, are enclosed in an evacuated chamber with outside connections to each element. The collector is a metal plate and the emitter is an oxide-metal composite which contains a very large number of metal filaments embedded in an insulating oxide matrix. The number of filaments normally exceed one million per square centimeter of exposed surface, having ends connected on the back side to a conducting plate for external connection.

Inventors

  • 👤 J Shelton
  • 👤 J Hagood
  • 👤 R Norman

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 17:56
CPC Classifications
H; H01; H01J; H01J1/00; H01J1/02; H01J1/30; H01J1/304; H01J21/00; H01J21/36

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 19 words
An electron tube as set forth in claim 1 wherein said rods are less than 1 micron in diameter.
Claim 2
Dependent Claim 35 words
An electron tube as set forth in claim 1 wherein said first electrode is an emitter requiring no heat for operation, current flow through the tube being a function of the field between the electrodes.

References Cited (Backward Citations)

US2287749A Cited
US2645742A Cited
US2916668A Cited
US3453478A Cited
US3466485A Cited
US3635157A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1976-07-16 1977-01-15 1977-07-17 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-07-16 1981-01-15 1981-07-17 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-07-16 1985-01-15 1985-07-17 $7700.00 Window Closed / Lapsed

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