GB309208A - Improvements in or connected with sound reproducing - Google Patents

Abstract

309,208. Wilson, S. K., and De Forest Phonofilms, Ltd. Dec. 2, 1927. Optical records and apparatus.-Sound photographically recorded on a strip is selectively reproduced or emitted in any desired locality and its volume or other characteristics varied by means controlled from the record which means may comprise notches or projections co-operating with electrical or mechanical devices. The reproduction may be effected in conjunction with a kinematograph and appear to issue from the audience or any desired position, for example the roof in the case of a scene depicting aeroplanes &c. In Fig. 1 the record film 1 is notched or cut away along the sides to control spring contacts 4 so as to actuate a relay 9 whereby the sound reproduced by a photo electric cell 11 and amplifier 10 is reproduced by speakers 7 and 8 or the speaker 6 as desired. The speakers may be disposed in any desired position in relation to the picture screen, and the film may have perforations instead of edge notches and move between clip contacts. In a modification the selection or control may be effected by markings 26, Fig. 9, on the strip record, for example at the opposite side of the pictures 24 from the sound record, and light is projected through such markings by a lamp 28, Fig. 8, on to a cell 30 controlling a relay 32 acting as in Fig. 1. The two lamps 28, 27 may be replaced by a single lamp and two refracting prisms which direct the light through slits on to the sound record and selecting markings respectively. Alternatively, the selecting means may operate to bring another sound record into operation, and may also control resistances to vary the volume or control different emission orifices from one reproducer.