Definition
of Television
Television is a telecommunication medium that is used for transmitting
and receiving moving images and sound. Television can transmit images that are monochrome (black-and-white), in
color, or inthree dimensions. The
word television comes from Ancient
Greek (tèle), meaning
"far", and Latin visio,
meaning "sight". Television may also refer specifically to a television set, television
program, ortelevision
transmission.
History of Televison
At
the dawn of television history there were two distinct paths of technology
experimented with by researchers.
Early inventors
attempted to either build a mechanical television system based on the
technology of Paul Nipkow's rotating disks; or they attempted to build an
electronic television system using a cathode ray tube developed independently
in 1907 by English inventor A.A. Campbell-Swinton and Russian
scientist Boris Rosing
German, Paul Nipkow developed a rotating-disc technology to
transmit pictures over wire in 1884 called the Nipkow disk. Paul Nipkow was the
first person to discover television's scanning principle, in which the light
intensities of small portions of an image are successively analyzed and
transmitted.
In
the 1920's, John Logie Baird patented the idea of using arrays of transparent
rods to transmit images for television. Baird's 30 line images were the first
demonstrations of television by reflected light rather than back-lit
silhouettes. John Logie Baird based his technology on Paul Nipkow's scanning
disc idea and later developments in electronics.
Charles Jenkins invented a mechanical television system
called radiovision and claimed to have transmitted the earliest moving
silhouette images on June 14, 1923
Cathode Ray Tube - Electronic Television
History
Electrnic television is based
on the development of the cathode ray tube, which is the picture tube found in
modern TV sets. German scientist, Karl Braun
invented the cathode ray tube oscilloscope (CRT) in 1897
Scientific principles of Television
Most simplistically, it works on radio waves, invisible wave
lengths that can be picked up by receivers and translated into electronic
signals that control displays on a "picture tube".
Most recently, digital signals have replaced analog waves, and of course many people are now receiving the electronic TV digital signals via cable, rather than by air-waves.
TV's, unlike just a radio, need to have a video tube, and an electronic tuner to put "color" pixels onto a screen of some sorts (plasma, or LCD's are more common today, than old picture tubes)
Most recently, digital signals have replaced analog waves, and of course many people are now receiving the electronic TV digital signals via cable, rather than by air-waves.
TV's, unlike just a radio, need to have a video tube, and an electronic tuner to put "color" pixels onto a screen of some sorts (plasma, or LCD's are more common today, than old picture tubes)
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