GB1334380A - Television receivers - Google Patents

Abstract

1334380 Television WATLER DEVELOPMENT CO L E J BAYNES and M J WATLER 17 Feb 1972 [2 Dec 1970] 57166/70 Heading H4F [Also in Division H1] The screen of a cathode ray tube comprises a phosphor which emits light of different hues according to the current density of the beam. Preferably the phosphor is a mixture of a blue phosphor with a non-linear orange phosphor which emits less light than normal at low current densities. The blue phosphor may be linear or may emit less light than normal at high current densities. Alternatively the mixture may comprise a non-linear yellow phosphor with linear red and blue phosphors. The orange or the yellow and red phosphors should comprise the imajor portion of the mixture. The tube may be used to display monochrome signals with pleasing colour hues varying with the intensity of the signals, bright areas appearing golden, intermediate areas in shades of brown, and dark areas in shades of blue or purple.