Patent · US Expired

Dispenser cathode

US5126622A · kind A · utility

6Cited by
2References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 7, 1990
Grant dateJun 30, 1992
Priority date
Expiry dateNov 7, 2010

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01J1/142
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A dispenser cathode comprises an electron emissive material including at least one selected from the group consisting of Ba and Ba oxide, a porous metal base body having a plurality of diffusing cavities and positioned on the electron emissive material and an alloy thin film layer consisting of scandium tungstate and tungsten which is disposed between the electron emissive material and the porous metal base body. Instead of the alloy thin film, a pellet containing scandium tungstate may be interposed between said electron emissive material and the porous metal base body. The activation aging time of the dispenser cathode of the present invention is greatly shortened as compared with the conventional dispenser cathode, and the damage of Sc by ion bombardment is prevented, and thus the stable thermoelectron emission can be obtained.

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