光電管を應用する音響發生の一裝置

Abstract

An apparatus which generates sound from a sound-picture is often more useful for the study of psychological acoustics than a sound recording apparatus like an oscillograph. The authors give the description of their own sound generating system by means of the photoelectric tube in two different modes.1)Rotating disk method in which sound pictures are arranged on a rotating disc (see Fig. I, B) in front of a photoelectric tube.2)Running film method in which sound pictures are arranged on celluloid film which runs in front of a photoelectric tube (as in the “talkie” system).Refer to the following figures inserted in the Japanese text.Fig. I, A, showing sound picture originally gotten from pronounced “a” by the oscillograph method.B, arrangement of the waves on a disc in rotating disk. method.Fig. II and III, showing a sound generating apparatus of the running film method in its front (Fig. II) and in its rear (Fig. III).A, a metal house containillg a photoelectric tube.B, an Window allowing the light-beam to reach the photoelectric tube.C, a lamp house with al amp inside.D, a lens srvinging to focus at B on the running film a sharp image of a miniature slit inserted at the base of C and at the same time serving as a condencer.E1, E2, film reels.F1, F2,s film Pulleys.G2, a film convaying sprocket.P1, P2, P3, Pulleys (Fig. III).M, synchronous motor (Fig. III).S, switches (Fig. III).Fig. IV, showing the diagram of the circuit used with the photoelectric tube. For fuller description, see the Japanese text.