Patent · US Expired

Electromagnetic focusing cathode-ray tube

US4439710A · kind A · utility

4Cited by
3References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 1, 1981
Grant dateMar 27, 1984
Priority date
Expiry dateJul 1, 2001

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01J29/68
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

An electromagnetic focusing cathode-ray tube in which plural pairs of magnetic material members are arranged within the tube along the tube axis, the magnetic material members in each pair are disposed to oppose each other in the direction of the tube axis with a gap defined therebetween, and the plural magnetic material member pairs and one or more permanent magnet disposed internally or externally of the tube are combined such that magnetic focusing fields having their senses or directions opposite to each other in the direction of the tube axis are formed at the respective gaps associated with the adjacent magnetic material pairs.

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