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Friday, August 6, 2010

Philo Farnsworth Debuts Electronic Television

Philo Farnsworth transmitted the first all-electronic television images on September 7th, 1927, making Broadcasting History.

The earliest inventions to transmit live video pictures in the early 1900's were based on mechanical devices that used spinning wheels and rotating mirrors to break an image into small definable voltage levels that could be sent in sequence to another set of wheels and mirrors that were synchronized to the sending equipment and caused the image to be reconstituted. Philo Farnsworth conceived of an electronic method that used vacuum tubes and the principle of photo electron emission (electrical current exciting phosphor and thereby creating light) to instantly transmit a live image. Although others had published these principles in scientific journals, no one had yet built such a device due to the complexity and expense. Philo, at age 16, was in high school when he first conceived of his system and showed it to his Chemistry teacher, Justin Tolman in 1922. At this time, broadcast radio was only 1 year old and almost non-existent in the isolated farm country of Idaho where the young Farnsworth lived. The major manufacturers of radio equipment were just then offering radios to consumers and had not even considered developing a television system.

At age 20, Farnsworth happened to meet George Everson, a charity fundraising expert. After hearing Philo describe his concept of electronic television, Everson convinced financiers from San Francisco to back the research and developmental costs of his television system with $25,000.00, quite a sum at that time. Philo put his invention into a patent application in January of 1927 and went to work in a Lab on 202 Green Street in San Francisco. Most of the parts for television did not even exist in 1927. Philo and brother-in-law Cliff Gardner constructed the video tubes from parts scavengered from old radio tubes. By September of 1927, most of the bugs had been worked out. On September 7th, a picture of a simple vertical line was transmitted using Philo's new video pickup tube, dubbed the Image Dissector.

Although Farnsworth's achievement was remarkable, his Image Dissector tube was only a start on the long journey to build a working television system that could pick up live scenes and transmit them through the air to receivers. Farnsworth's Dissector tube required an impractical amount of light to create any viewable picture of a live scene. Though his tube did pick up live video, performers were required to wear bizarre blue and red makeup to have any contrast in their faces. The Dissector tube, however, was excellent for film pickup, where a relatively intense light could be brought to bear on a film frame. The Image Dissector became the preferred method to transmit motion pictures.

Many problems had yet to be solved to transmit live action, and for Farnsworth many battles remained before he would realize any financial profit from his invention. His greatest battle proved to be the legal fight to be named the inventor of all-electronic television. His nemesis was no less than the monolithic Radio Corporation of America, headed by David Sarnoff, who had leveraged the technologies for basic radio circuit patents into a force that few could challenge. Vladimir Zorykin, a Russian emigrant, had submitted a patent application for a similar device in 1923 when he worked for Westinghouse, but his device was never built or demonstrated. Sarnoff successfully kept the patent challenge in the courts for years hoping to invent a better pickup tube while at the same time wearing down the competition (Farnsworth). Zorykin indeed invented a better pickup tube, dubbed the Iconoscope, in 1933. This tube made possible the pickup of live images in natural light, and this technology became the basis of RCA's television system which was adopted and eventually implemented industrywide over the next three years.

Farnsworth did eventually receive credit for his invention and RCA paid him royalties for many years, but Farnsworth never received either the proper credit or financial renumeration that was due him.


http://www.farnovision.com

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