Patent · US Expired

Method for making a cathader with integral shadow grid

US4994709A · kind A · utility

8Cited by
2References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 22, 1989
Grant dateFeb 19, 1991
Priority date
Expiry dateMar 22, 2009

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01J9/04
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A very fine-mesh, non-emissive shadow grid is formed on the smooth emissive surface 16 of a thermionic cathode 12 by deposition from a vapor a continuous layer 22 of non-emissive conductive material. Between the elements 24 of the grid the non-emissive material is removed by bombardment through an apertured mask to restore emissivity between the elevated grid elements 24.

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