Patent · US Expired

Method of forming a fluorescent screen for a color picture tube

US4324850A · kind A · utility

9Cited by
1References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 28, 1980
Grant dateApr 13, 1982
Priority date
Expiry dateFeb 28, 2000

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S430/153
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

In forming a fluorescent screen for a color picture tube having triads of phosphor materials of the three primary colors arranged in a predetermined pattern on the inner surface of a panel, a photosensitive film which exhibits stickiness when exposed to a threshold amount of light is formed on the inner surface of the panel. Locations of the photosensitive film where the three color phosphor materials respectively occupy are exposed to light from a light source through a shadow mask mounted to the panel. The amount of exposure light for a first color phosphor material is the threshold or above and that for second and third phosphor materials is below the threshold. After completion of the light exposures for the first to third color phosphor materials through the shadow mask, the shadow mask is dismounted from the panel and the first color phosphor material is deposited onto the photosensitive film. A first back exposure is then carried out and the second color phosphor material is deposited onto the photosensitive film. Thereafter, a second back exposure is carried out and the third color phosphor material is deposited onto the photosensitive film.

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