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Who invented television? Television, as you know, is a rather complicated process. Whenever such a process is developed, you can be sure a great many people had a hand in it and it goes far back for its beginnings. So television was not "invented" by one man alone. The chain of events leading to television began in 1817, when a Swedish chemist named Jons Berzelius discovered the chemical element "selenium." Later it was found that the amount of electrical current selenium would carry depended on the amount of light which struck it. This property is called "photoelectricity." In 1875, this discovery led a United States inventor, G. R. Carey, to make the first crude television system, using photoelectric cells. As a scene or object was focused through a lens onto a bank of photoelectric cells, each cell would control the amount of electricity it would pass on to a light bulb. Crude outlines of the object that was projected on the photoelectric cells would then show in the lights on the bank of bulbs. The next step was the invention of "the scanning disk" in 1884 by Paul Nipkow. It was a disk with holes in it which revolved in front of the photoelectric cells, and another disk which revolved in front of the person watching. But the principle was the same as Carey's. In 1923 came the first practical transmission of pictures are over wires, and this was the accomplished by Baird in England and Jenkins in the United States. Then came great is improvements in the development of television cameras. Vladimir Zworykin and Philo Farnsworth each developed a type of camera,.one known as "the inconoscope" and the other as "the image dissector." By 1945, both of these camera pickup tubes had been replaced by "the image orthicon." And today, modem television sets use a picture tube known as a "cathode-ray tube." In this tube is an electric gun which scans-the screen in exactly the way the beam does in the camera tube to enable us to see the picture. Of course, this doesn't explain in any detail exactly how television works, but it gives you an idea of how many different developments and ideas had to be perfected by different people to make modem television possible. For Details
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