Abstract: Disclosed is a high luminance color screen for cathode tubes, comprising two fluorescence luminophors of different colors, the visible trace of which, under the effect of electron bombardment, has a color which can be adjusted by the acceleration voltage of the beam of said electrons. Said voltage is variable, during operation, between two extreme values V.sub.o and V.sub.1, in which the two luminophors are arranged on the transparent support of said screen is superimposed layers formed by powders of crystals of each of the said luminophors, separated from one another by plane faces. Said screen is characterized mainly by the fact that the barrier with plane faces comprises a first layer of silicon dioxide, a layer of zinc sulfide and a second layer of silicon dioxide, the layer of zinc sulphide being included between the two layers of silicon dioxide.

Abstract: For improving the contrast of information displayed on the screen, there is placed in front of this latter a filter comprising a matrix of channels pierced in a photosensitive glass plate. The pierced plate is covered over the whole of its surface with a blackened deposit so as to reduce to the maximum its coefficient of reflection. Thus filters can be formed readily on request, according to the direction of observation in particular, with a good coefficient of transmission and improved contrast.