GB571945A - Improvements relating to stereoscopic cinematography - Google Patents

Abstract

571,945. Stereoscopic kinematography. BRITISH THOMSON-HOUSTON CO., Ltd., and CASTELLAIN, A. P. June 1, 1943, No. 8765. Drawings to Specification. - [Classes 97 (i) and 98 (ii)] Means for producing stereoscopic kinematograph films comprise a photo-electric image converter, such as an ionoscope, on to the screen of which right- and left-eye images of the scene are projected, means for scanning corresponding lines alternately of each image, a cathoderay tube having its beam controlled in intensity by the amplified output of the image converter and scanned in synchronism with the scanning of the images on the screen of the converter so as to produce on the cathode-ray' tube screen a line of each image alternately, together with a photographic film which is moved uniformly in front of the cathode-ray tube screen, whereby either separate right- and left-eye images or interlaced right- and left-eye images are imprinted line by line on the film. The two images may be arranged one above'the other on the screen of the image converter and scanned in vertical lines extending over their combined height, the corresponding scans of the cathode-ray beam being across the width of the film, so that the images of a pair appear side by side and with their vertical dimensions transversely of the film. Alternatively, the scan of the cathode-ray beam may be such that a composite interlaced image is formed, the projected image of which is viewed through a grid, and consisting of lines of each of the images arranged alternately, the vertical dimensions of the images again extending transversely of the film. The proportions of the images on the film may be changed by control of the beam and restored during projection from the film by a system such as that described in Specification 571,944. Colour records may be made by a disc comprising colour segments arranged to intercept the light forming the images on the screen of the photo-electric converter. Background or other scenes may be superimposed on the scene depicted by additional modulation of the recording cathoderay tube, obtained from a second image converter.