Improvements in or relating to apparatus for projecting optical images

Abstract

Abstract 557,771. Projection systems ; cathode-ray tubes. CINEMA-TELEVISION, Ltd. (Szegho, C. S.). Sept. 1, 1942, No. 12341. [Class 97 (i)] [Also in Group XL] In a combination for projecting images, comprising a cathode-ray tube, a concave mirror, and an aspherical plate or system correcting spherical aberration of the mirror, the mirror is formed on a part of the envelope of the tube or is disposed within the envelope ; the correcting plate &c. may be external to the tube, or may form part of the tube, or may form part of the tube envelope. Fig. 2 shows a tube wherein the mirror 9 and correcting plate 12 form part of the envelope, the mirror being disposed around the aperture of the electron gun 10 having its axis coincident with the central radius of a spherically convex fluorescent screen 8. As shown in Fig. 3, the fluorescent screen 13 is flat, and an annular convex mirror 14 reflects the image to the concave mirror 15 reflecting through a correcting plate 16. The concave mirror may be obtained by coating the envelope or by the provision of a metallic mirror within it, and the axis of the electron gun may make an angle with a normal to the fluorescent screen surface.

Inventors

No inventors recorded.

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