GB638443A - Improvements in or relating to apparatus for recording television or like pictures on cinematographic film - Google Patents

Abstract

638,443. Television. CINEMA-TELEVISION, Ltd., and JESTY, L. C. Oct. 31, 1947, No. 29108. [Class 40 (iii)] In an arrangement for recording television pictures, reproduced by interlaced scanning, on intermittently moving kinematographic film some only or parts of some, or parts of all field traverses are recorded and the resulting gaps filled in by electrical or optical means. In one embodiment employing a standard intermittent motion camera with a 50 per cent pull-through time and in which the picture to be recorded is reproduced by a double interlaced scan on the screen of a picture reproducing tube the camera shutter and pullthrough mechanism are arranged so that alternate field scans only are recorded and the scanning spot dimension is increased in a direction perpendicular to the direction of line scanning so that the lines of the recorded single field are of double thickness. In a further embodiment employing a camera with a pull-through time of 12¢ per cent the whole of one field and part of the next (interlaced) field is recorded, the lines of double thickness being arranged to appear at the top and bottom of the recorded picture with a normal double interlaced picture at the centre. The increase in size of the scanning spot which is necessary to trace the double-width lines may be effected by employing electron-optical components in the gun of the picture-reproducing tube or by applying an additional, high-frequency, scanning component to the scanning beam in a directional perpendicular to the line scanning direction. Alternatively, a single line scan on the picture reproducing tube may be used and cylindrical lens means employed to widen the spot, the deflection in the frame direction being obtained by mechanical scanning means.