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:
Nov. 08, 1988
Filed:
May. 28, 1987
Applicant:
Inventors:
Shigehiko Yamamoto, Tokorozawa, JP;
Isato Watanabe, Hachioji, JP;
Sadanori Taguchi, Tokyo, JP;
Susumu Sasaki, Kokubunji, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01J / ; H01J / ;
U.S. Cl.
CPC ...
3133 / ; 313630 ; 313632 ; 252515 ; 252521 ;
Abstract
An impregnated cathode comprising a refractory porous body whose pore parts are impregnated with an electron emissive material including barium and a thin film layer comprising tungsten, scandium and/or an oxide of scandium, deposited on the surface of the refractory porous body, characterized in that the thin film layer contains an oxide of tungsten, and/or an oxide of tungsten and scandium, has a distinguished electron emission property and a long life.