GB351972A - Improvements in or relating to television and like systems - Google Patents

Abstract

351,972. Television. MARCONI'S WIRELESS TELEGRAPH CO., Ltd., Marconi House, Strand, London.-(Assignees of Cioffari, B. ; 88, Washington Avenue, New Rochelle, Westchester, New York, U.S.A.) April 1, 1930, No. 10391. Convention date, April 1, 1929. [Class 40 (iii).] In television a scanning method comprises deflecting a light beam along a plurality of spaced paths and successively controlling the beams to trace a plurality of additional paths interspersed between the first spaced paths. A mirror disc 11, Fig. 2. deflects a beam of light from a source 18 along a plurality of paths in accordance with the number and tilting of the mirrors 1, 2, 3, &c. Each mirror deflects a beam across a member 10 consisting of a plurality of mirrors 12, 13, 14, &c., each inclined to its neighbours vertically as well as horizontally. As the first beam from mirror 1 passes across mirror 16 the screen 17 is scanned from d<1> to c<1>. When the beam passes across mirror 15, the screen 17 is again scanned along its breadth, but the second scanning line is spaced vertically from the first scanning line by virtue of the vertical tilt of mirror 15. Similarly the mirrors 14, 13, 12 produce scanning lines vertically spaced apart and lying between the scanning line produced by mirror 1 in conjunction with mirror 16, and that produced by mirror 2 in conjunction with mirror 16. Thus each mirror on the disc 11 results in five scanning lines on the screen, there being five mirrors on the member 10. Instead of a mirror disc 11 a lens disc 21, Fig. 5, may be employed.