n.
Electronic system for transmitting still or moving images and sound to receivers that project a view of the images on a picture tube or screen and recreate the sound.
Early versions (190020) of the cathode-ray (picture) tube , methods of amplifying an electronic signal, and theoretical formulation of the electronic-scanning principle later became the basis of modern TV. RCA demonstrated the first all-electronic TV in 1932. Colour TV (in the 1950s), cable TV systems (introduced in the 1960s), and recording or playback machines (in the 1980s; see VCR ) followed. Digital high-definition (HDTV) systems (1990s) provide sharper, clearer pictures and sound with little interference or other imperfections and have the potential to merge TV functions with those of computers.