Patent · US Expired

Color cathode ray tube

US6411025B1 · kind B1 · utility

3Cited by
1References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 7, 2000
Grant dateJun 25, 2002
Priority date
Expiry dateFeb 7, 2020

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01J2229/8616
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A color cathode ray tube is provided having a shadow mask or screen designed to an optimum state or whose panel's light absorption coefficient is set to an optimum value even if the panel has a high wedge ratio, thereby obtaining excellent bright uniformity characteristics. The color cathode ray tube includes a panel with a wedge ratio of more than 170%; a screen onto which electronic beams are scanned and on which fluorescent dots coated with RGB fluorescent materials and a black matrix layer filled with a black coating material throughout all the regions except for the fluorescent dots are formed; and a shadow mask on which a plurality of slots are arranged corresponding to the fluorescent dots, wherein the dot diameter at the corner portion of a screen is larger than that at the center portion by about 100-127%, the slot width at the corner portion of a shadow mask is larger than that at the center portion by about 105-133%. Accordingly, even though the wedge ratio is more than 170%, more than 50% bright uniformity (BU) characteristics are assured, and a tint glass can be used in fabricating a panel, thereby reducing the fabrication cost and weight of the color cathode ray tube.

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