Faceplate means for improving dielectric strength of cathode-ray tubes

Claim 1

In combination a cathode-ray tube display system having a faceplate assembly comprising, a first faceplate of the fiber optic type, said faceplate-type exhibiting random areas of low dielectric strength between the surfaces thereof, a phosphor screen located on the interior surface of said first faceplate, an electrically conductive coating on the phosphor screen remote from the interior surface of said first faceplate, a second faceplate means for maintaining contact between a surface of said second faceplate and the exterior surface of said first faceplate to form said faceplate assembly, said faceplate assembly exhibiting greater dielectric strength than that of said first faceplate, and a second electrically conductive means associated with the surface of said second faceplate remote from said first faceplate, and means for maintaining said electrically conductive coating at a high electrical potential with respect to said second electrically conductive means to establish a potential gradient therebetween, said faceplate assembly exhibiting sufficiently high dielectric strength to substantially eliminate high voltage electrical breakdown between the remote surfaces of said faceplate assembly.