Patent · US Expired

Cathode for electron tube

US4924137A · kind A · utility

23Cited by
3References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 8, 1989
Grant dateMay 8, 1990
Priority date
Expiry dateFeb 8, 2009

Classification

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

Abstract

An oxide-coated cathode for an electron tube comprises a layer (2) of an electron-emissive substance. This layer (2) contains: an alkaline earth metal oxide as a principal component containing at least Ba; an oxide of Sc; and at least one heat-resisting oxide selected from the group consisting of oxides of Al, Si, Ta, V, Cr, Fe, Zr, Nb, Hf, Ta, Mo and W.

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