The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 08, 1981
Filed:
Nov. 06, 1979
Denki Kagaku Kogyo Kabushiki Kaisha, Machidashi, JP;
Abstract
A thermionic cathode includes an electron emitting tip, lanthanum hexaboride tip supporting heaters in close contact with both sides of the tip and supporting the tip, and elastic electroconductive members in pressure contact with outer surfaces of the tip supporting heaters for supplying electric current. The tip supporting heaters are obtained by cutting lanthanum hexaboride having high anisotropy due to its layered structure so as to form a pair of parallel planes perpendicular to a pressing direction when hot-pressed, and abrade-polishing the parallel planes. The tip supporting heaters are brought into close contact with the tip and the elastic electroconductive members at the resulting smooth surfaces thereof. The apparatus of the invention has a prolonged lifetime and high efficiency.