Patent · US Expired

Direct heating cathode for high frequency thermionic tube

US4429250A · kind A · utility

11Cited by
4References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 18, 1981
Grant dateJan 31, 1984
Priority date
Expiry dateSep 18, 2001

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01J1/15
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

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.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.