GB451959A - A system, or method, of scanning an image: for use in conjunction with any moving spot scanning device, for television or the like - Google Patents

Abstract

451,959. Television transmitters. RICHARDSON, H. A., Darley House, Marlboro' Road, Buxton. Feb. 16, 1935, No. 5017. Addition to 425,660. [Classes 39 (i) and 40 (iii)] An image A<1> B<1> is projected on the emissive surface CA of a photo-electric cell V and is scanned by a spot of radiation of different frequency. If the scanning radiation is of lower frequency, incidence on a bright part produces a small decrease in the current reaching the anode A, and incidence on a dull part produces a large decrease. According to modifications : a plurality of images are used for colour or stereoscopic reproduction, Figs. 2, 7, 8, and 12 (not shown) ; the work factor is decreased by bombarding the rear of the cathode with electrons, Fig. 3 (not shown) ; the scanning radiation is obtained from a cathode-ray tube, Fig. 4 (not shown) ; the tube acts as an electron multiplier, Fig. 9 (not shown), with the image incident on one electrode and the scanning-spot on a second, Fig. 5 (not shown), or the electrode receiving the image is not part of the multiplier, Figs. 10 and 11 (not shown) ; the electrons being focused by a coil, Fig. 13 (not shown), or in the multiplier the electrons oscillate between two electrodes and at the same time move towards an anode Fig. 14 (not shown) ; an electronic image is traversed over a stationary spot of radiation, Figs. 6 and 8 (not shown).