GB717448A - Improvements in or relating to optical projection screens - Google Patents

Abstract

717,448. Projection screens. DECCA RECORD, CO., Ltd. July 22, 1953 [Aug. 8, 1952], No. 20047/52. Class 97(1) A rigid screen is provided with a housing which stands upright on a horizontal surface. the screen being withdrawable upwardly from the housing to an operative position in which it is tilted forward at a small angle. The screen may be housed in an inclined position and withdrawn along a straight guide, especially if the housing also contains a loud speaker. A weight or spring counter-balance may be provided. Alternatively. as shown in Fig. 5. the screen 21 is mounted in a frame 22 of which the side members 23 slide in vertical channels in the side walls of a cabinet 25. At the upper end of the screen movement downward extensions 27 of the side members 23 enter recesses 20 in the rear walls of the channels, thus providing the forward tilt of the screen and holding it raised. Springs may assist the movement into the recesses. Adjustable screw abutments may limit the tilt. Alternatively the screen may be pivoted to blocks which slide in channels in the side walls of the cabinet and which carry adjustable means to limit the pivotal movement. Locking means for the blocks may hold the screen raised, or the screen itself, after pivoting, may engage a shoulder on the casing. Feet 28 fold flat for stowage. The screen surface is of metallic paint.