GB365241A - Improvements in or relating to television or like apparatus - Google Patents

Abstract

365,241. Television. BAIRD, J. L. and BAIRD TELEVISION, Ltd., 133, Long Acre, London. Nov. 12, 1930, Nos. 34064/30 and 23895/31. [Class 40 (iii).] In a two-way television system, in which an image of the distant person or object is reconstituted wholly or in part within the solid angle formed by the local scanning-beams, the scanning and reconstitution at each station are severally continuous, and the beams scanning the local object are of low luminous value. Light from a source 1 passes through a mask 2, a thin sheet of ebonite 3 and large lenses 4 in a spiral in a scanning-disc 5 to form scanning- beams, which are reflected from the observer 6 to sensitive cells 7. Incoming signals modulate a glow lamp 8, from which light is reflected to the eye of the observer by small reflectors 10 behind spirally arranged holes 9 in the scanning- disc. According to modifications : a mirror drum and a scanning-disc are used, Fig. 3 (not shown) ; two mirror drums co-operate with a disc having large clear apertures intercalated with light-diffusing screens, Fig. 4 (not shown) ; light from the source 1 and the modulated glow-discharge lamp are transmitted in slightly different directions to a mirror drum, from which the light is reflected to a disc with apertures alternately covered with diffusive material and filters opaque to visible light, Fig. 5 (not shown). Specification 288,882, [Class 40 (iii), Telegraphs, Electric], is referred to.