Television
Essay by review • February 24, 2011 • Essay • 422 Words (2 Pages) • 885 Views
TELEVISION We have at least a television in our home. television allows us to hear and see events as soon as they happen. If our grandma's mother or father see TV, they'll surprised
and say 'This is diablo's machine!'. We watch TV at least two hour in a day. HOW WORKS TV? When a TV program is broadcast the sound and picture are sent out simultaneously by two different radio systems. The TV camera takes the picture. Camera is the most important part of the camera. The light from the object is allowed to fall on a light sensivite plate located inside the camera tube by the lens. This plate consists of thousands of light sensivite particles which act as photoelectric cells. Each photoelectric cell gives off electrons in the same proportion as the light falling on it. This forms an image on the plate. The bright and dark spots form an electric current which leaves the transmitter as carrier waves. These waves are picked up by the receiver. The TV receiver picks up both the sound and the picture. The antenna of the TV set picks up the weak current and passes it to a cathode ray tube which is called the picture tube. The electron beam scans the screen of the picture tube in exactly the same way that it scanned the target of the camera tube and a picture is formed on TV screen. The image on the screen changes 25 times a second and, since we can't detect individual pictures moving at this speed, we see a continuously moving image. WHO INVENTED THE TV? Television wasn't invented by a man. Many people helped for inventing TV. (For example German Nipkow (1884) , Russian Rosing (1911) , American Zworikin...) DEVELOPERS 1884Ð" Nipkow**German** 1911Ð" Rosing**Russian**-Zworikin**American** 1923-1928Ð" Baird**English** 1923-1928Ð" Barthelemy-Halweck**French** TV's STEPS in WORLD Ð" NÐ"ÑœPKOW He made a TV and he invented scanning disk with holes. Ð" ROSÐ"ÑœNG & ZWORYKÐ"ÑœN They invented first vision on screen. Ð" BAIRD & HALWECK-BARTHELEMY Baird in England , Halweck and Barthelemy in France transmit blur visions with radioelectiric waves. Ð" 1947 The visions became clear visions Ð" 1951 Colored TV was invented. Ð" 1953 & 1962 Eurovision in 1953 , Mondovision in 1962 were broadcasted and TV became a important thing in world. TV's STEPS in TURKEY Ð" 1963 A education center for TV was builded. Ð" 1966 A small
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