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:
Jan. 31, 1984
Filed:
Sep. 18, 1981
Applicant:
Inventors:
Guy Clerc, Paris, FR;
Arvind Shroff, Paris, FR;
Assignee:
Thomson-CSF, Paris, FR;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01J / ;
U.S. Cl.
CPC ...
313336 ; 3133 / ;
Abstract
A direct heating thermionic emission cathode for high frequency tubes of the diode, tetrode or pentode type. It comprises a pyrolytic graphite support and a lanthanum hexaboride-based thermoemissive material, these elements being separated by a layer which constitutes a diffusion barrier and comprises a tantalum or hafnium carbide, a metal of the platinum group or a boron compound.