Patent · US Expired

Cathode ray tube having a focus mask and support frame assembly with an improved border

US6639344B2 · kind B2 · utility

8Cited by
5References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 14, 2001
Grant dateOct 28, 2003
Priority date
Expiry dateFeb 4, 2022

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01J29/07
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

The present invention provides a focus mask and frame assembly for a cathode ray tube. The cathode ray tube includes an evacuated envelope enclosing a luminescent screen, a focus mask, and a support frame having at least two long sides for supporting the focus mask between the electron gun and the screen within the cathode ray tube. The focus mask has an active array area formed of a plurality of strands and cross wires separated by an insulating material and defining a plurality of focusing apertures within the array area. A border is attached to the strands opposite the insulating material along the upper and lower outer edges of the active array area. The borders extend into the active array area such that the cross wires overlie a portion of the borders and the borders form focusing apertures with the strands along the upper and lower edges of the array.

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