GB358433A - Improvements in and relating to television systems - Google Patents

Abstract

358,433. Television. MALONEY, P. E., 9. Main Street, Dundrum, Co. Dublin. July 2, 1930, No. 20050. [Class 40 (iii).] Two or more zones Z3, Z<9>, Fig. 10, of a rotating scanning member D with apertures on a spiral or helical curve, are simultaneously employed for transmitting or receiving a single object O, or two or more of the zones Z<1>, Z<2>, Fig. 3, not near opposite ends of a diameter, are used for transmitting and receiving, to obtain duplex working. The rotating member may be in the form of a drum, Fig 2 (not shown). An object O is scanned by the zone Z<1> of the disc D and the corresponding image I is synthesized by the zone Z<1> of the disc D<1>. An object O<1> is simultaneously scanned and its image I<1> synthesized by the zones Z<2>. According to modifications : reversal of the images is prevented by turning the disc D<1> back to front as compared with the disc D, Fig. 4 (not shown); to obtain correct inclination of the image to the vertical the positions of the light-sensitive cell L and the variable light source E are interchanged by pivoting them about an intermediate axis, Fig. 5 (not shown), by using one cell and two light sources and moving them circumferentially, Fig. 6 (not shown), or by optical means, Fig. 7 (not shown) ; the light source is on the same side of the scanning disc as the observer, Fig. 8 (not shown). Stereoscopic reproduction is obtained by using two zones to scan two views of the object, Fig. 9 (not shown). For colour reproduction coloured filters, or cells sensitive to, and sources emitting, single colours are employed in conjunction with a plurality of zones. To transmit two areas of the object 0 simultaneously, the light from the object is divided by mirrors 10, 11 to opposite zones Z<3>, Z<9> and reconverted into one beam at the receiver by similar mirrors. According to modifications : the whole area of revolution of the disc is used, Fig. 11 (not shown) ; one zone is used for monitoring, Fig. 12 (not shown). Specifications 280,630, 295,653, 309,965, [all in Class 40 (iii), Telegraphs, Electric], and 355,795 are referred to.