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:
Mar. 11, 1980
Filed:
Apr. 18, 1978
Masaaki Futamoto, Tsukui, JP;
Ushio Kawabe, Hamuramachi, JP;
Shigeyuki Hosoki, Hachioji, JP;
Tsutomu Komoda, Hinodemachi, JP;
Shigehiko Yamamoto, Tokorozawa, JP;
Hitachi, Ltd., , JP;
Abstract
A cathode for an electron source according to this invention comprises an emitter tip made of an electron emissive material, a filament for holding the emitter tip, and a binder for binding the emitter tip and the filament, the filament and the binder being made of glassy carbon. The binder can have a carbide or boride powder incorporated therein. The cathode according to this invention can be produced by using a thermosetting resin of predetermined shape as the starting material of the filament, fixing the emitter tip to a predetermined position of the thermosetting resin with the adhesive agent made of the raw thermosetting resin, and heating the resultant assembly in a non-oxidizing atmosphere to carbonize the resinous portions. This cathode is structurally very simple. Moreover, the adhesion between the filament and the emitter tip is excellent, and the emitter tip can be heated to high temperatures above 2,000.degree. C. by causing current to flow through the cathode.