High brightness projection TV system using one or more CRTs with a concave phosphor surface acting to concentrate light into a lens system

摘要

A multiple tube projection television system. At least two image generating cathode ray tubes are provided, having an image generating surface which is concave. The radius of curvature of the image generating tubes is selected to be between 1.2 and 2 times the image diagonal of each tube. Dichroic mirror means are provided to combine the images produced from each tube. A projection lens system is positioned at an optical distance from each tube which is substantially equal to the radius of curvature of the concave phosphor surface. The combination provides for an optimum amount of light to the entrance aperture of the projection lens system.