who invented tv?

Television is a telecommunication system for broadcasting and receiving moving pictures and sound over a distance. The term has come to refer to all the aspects of television from the television set to the programming and transmission. The word is derived from mixed Latin and Greek roots, meaning "far sight": Greek t??e "tele", far, and Latin visio-n, sight.The television was not invented by a single person, but by a number of scientists' advancements contributing to the ultimate all-electronic version of the invention. The origins of what would become today's television system can be traced back as far as the discovery of the photoconductivity of the element selenium by Willoughby Smith in 1873 followed by the work on the telectroscope and the invention of the scanning disk by Paul Nipkow in 1884. All practical television systems use the fundamental idea of scanning an image to produce a time series signal representation. That representation is then transmitted to a device to reverse the scanning process. The final device, the television (or TV set), relies on the human eye to integrate the result into a coherent image.Electromechanical techniques were developed from the 1900s into the 1920s, progressing from the transmission of still photographs, to live still duotone images, to moving duotone or silhouette images, with each step increasing the sensitivity and speed of the scanning photoelectric cell. John Logie Baird gave the world's first public demonstration of a working television system that transmitted live moving images with tone graduation (grayscale) on 26 January 1926 at his laboratory in London, and built a complete experimental broadcast system around his technology. Baird further demonstrated the world's first color television transmission on 3 July 1928. Other prominent developers of mechanical television included Charles Francis Jenkins, who demonstrated a primitive television system in 1923, Frank Conrad who demonstrated a movie-film-to-television converter at Westinghouse in 1928, and Frank Gray and Herbert E. Ives at Bell Labs who demonstrated wired long-distance television in 1927 and two-way television in 1930.Color television systems were invented and patented even before black-and-white television was working; see History of television for details.

Completely electronic television systems relied on the inventions of Philo Taylor Farnsworth, Vladimir Zworykin and others to produce a system suitable for mass distribution of television programming. Farnsworth gave the world's first public demonstration of an all-electronic television system at the Franklin Institute in Philadelphia on 25 August 1934.

Regular broadcast programming occurred in the United States,[1] the United Kingdom,[2] Germany,[3] France,[4] and the Soviet Union[5] before World War II. The first regular television broadcasts with a modern level of definition (240 or more lines) were made in England in 1936, soon upgraded to the so-called "System A" with 405 lines. Regular network broadcasting began in the United States in 1946, and television became common in American homes by the middle 1950s. While North American over-the-air broadcasting was originally free of direct marginal cost to the consumer (i.e., cost in excess of acquisition and upkeep of the hardware) and broadcasters were compensated primarily by receipt of advertising revenue, increasingly United States television consumers obtain their programming by subscription to cable television systems or direct-to-home satellite transmissions. In the United Kingdom, France, and most of the rest of Europe, on the other hand, operators of television equipment must pay an annual license fee, which is usually used to fund (wholely or partly) the appropriate national public service broadcaster/s (e.g. British Broadcasting Corporation, France Télévisions, etc.).







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