Abstract: The projection type display device includes a light source tube having electron beam generation means and a light-emitting portion consisting of a fluorescent layer emitting light by means of electron beam excitation, a light valve for forming an optical image corresponding to a picture signal, and an optical system for projecting upon a screen the optical image of the light valve by means of the light irradiated from the light source tube. The convex lens is disposed between the light valve and the light-emitting portion, such that the diffusing light emitted from the light emitting portion is condensed toward the light valve. As a result, the diffusing light from the light-emitting portion having a smaller area than the area of the light valve is supplied to the light valve in a substantially parallel beam. Further, the reflection layer for reflecting and condensing the diffusing light emitted from the light-emitting portion toward the light valve may be provided.

Abstract: A large-size screen display apparatus, having a plurality of projection display devices arrayed in a matrix arrangement to form one large screen, is for displaying characters and the like. A screen of each projection display device consists of a transparent plate disposed on the light entrance side and a diffusing surface disposed on the viewing side. Further, and the periphery of the transparent plate is mounted to a housing of the display apparatus. Light rays emanated from a projection lens are reflected by the transparent plate, whereby an optical image is formed on the entire diffusing screen. Since the optical image is displayed on the entire surface of the diffusing screen, no non-display areas will appear on the screen even when the plurality of projection display device are arranged in the matrix array.