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:
Dec. 25, 1990
Filed:
Jun. 10, 1988
Applicant:
Inventors:
Etsuji Kimura, Saitama, JP;
Hisao Nakanishi, Kyoto, JP;
Assignees:
Mitsubishi Kinzoku Kabushiki Kaisha, Tokyo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01J / ;
U.S. Cl.
CPC ...
3133 / ;
Abstract
A cathode for an electron tube comprises a base (1) including nickel as a major element and including at least silicon as a reducing element, and it further comprises an electron-emissive layer (5) coated on the base, including not only alkaline earth metal oxide (8) containing at least barium but also scandium oxide. The scandium oxide (4) is in the form of dodecahedral or prismatic polyhedral crystals and dispersed in the electron-emissive layer in the range from 0.1 to 20 wt. %.