GB388404A - Improvements in or relating to television and the like systems - Google Patents

Abstract

388,404. Television. GRAMOPHONE CO., Ltd., Hayes, Middlesex, and CONDLIFFE, G. E., Thorncombe, Fulmer Road, Gerrards Cross, Buckinghamshire. Aug. 18, 1931, No. 23275. [Class 40 (iii).] A scanning member, e.g. a drum 13, bearing a plurality of scanning elements, e.g. mirrors or lenses, translates a series of images 15, 16 of an object 1 over a plurality of scanning apertures 10, 11, 12 co-operating with a single transmission line fed from a cell 20, successive images 15, 16 being relatively displaced at rightangles to their direction of translation and each scanning element taking part in scanning more than one line of an image. The apertures 10, 11, 12 are spaced apart by a distance equal to or greater than the width of an image, and each in turn scans a line of an image, cooperating with a reflector 17, 18, 19 and the cell 20. The film 1 is moved intermittently, the mirror drum 13 having certain mirrors blackened to avoid scanning during the movement of the film. If the film is moved uniformly, the drum 13 has all its mirrors mounted tangentially. Each aperture 10, 11, 12 may be subdivided, the corresponding subdivisions being associated with a separate cell and transmission line. At the receiver three sources of light replace the apertures 10, 11, 12 and a screen is used to render only one effective at a time. A plurality of such scanning arrangements may co-operate to scan a picture in zones, one or more zones being scanned more finely than the others if desired. According to the Provisional Specification, each aperture may be associated with a separate transmission channel, the apertures being separated by a distanceless than the width of the picture.