GB684587A - Method of making and copying records - Google Patents

Abstract

684,587. Photographically duplicating sound records. LOEWE OPTA AKT.-GES. June 11, 1951 [June 12, 1950], No. 13756/51. Drawings to Specification. Class 98 (ii). [Also in Group XXXVIII] A method. and apparatus for making and copying records of electrical sound currents, comprises the employment of a rotating cylinder which is displaced axially by a lead-screw with reference to a recording device whereby a spiral record is impressed on said cylinder, and one or more copying tapes are unrolled by, and in contact with, the cylinder, whereby the record track being made is immediately transferred to the copying tape or tapes. In an alternative embodiment the lead screw is replaced by a keyed shaft along which the cylinder is drawn by cords passing over pulleys. The sound track on the cylinder may be in the form of a groove cut by a stylus, and the copying effected by inking the cylinder and printing the sound track on to the tapes for optical reproduction. In another method of recording, an electric charge picture is formed on medium consisting of a semi-conductor, such as selenium, or, eventually, of a non-conductor or of a conductor with mosaic sub-division which is arranged as a coating on the cylinder, the recording member consisting of an electronic valve with controlled electronic beam which influences the recording layer, through a Lenard aperture. The electric charge picture may be made visible by colouring matter contact copies obtained on a photographic tape by employing a light source inside the cylinder, which must in this case have a transparent wall.