Future Carrier (Including Costs)

[Modern Elmo]

Fascinating facts about the invention
of the television by Philo T. Farnsworth in 1927.

TELEVISION

In 1921 the 14-year-old Mormon had an idea while working on his father's Idaho farm. Mowing hay in rows, Philo realized an electron beam could scan a picture in horizontal lines, reproducing the image almost instantaneously. This would prove to be a critical breakthrough in Philo Farnsworth's invention of the television in 1927.

Earlier TV devices had been based on an 1884 invention called the scanning disk, patented by Paul Nipkow. Riddled with holes, the large disk spun in front of an object while a photoelectric cell recorded changes in light. Depending on the electricity transmitted by the photoelectric cell, an array of light bulbs would glow or remain dark. Though Nipkow's mechanical system could not scan and deliver a clear, live-action image, most would-be TV inventors still hoped to perfect it.

Not Philo Farnsworth. In 1921 the 14-year-old Mormon had an idea while working on his father's Idaho farm. Mowing hay in rows, Philo realized an electron beam could scan a picture in horizontal lines, reproducing the image almost instantaneously. It would prove to be a critical breakthrough.

But young Philo was not alone. At the same time, Russian immigrant Vladimir Zworykin had also designed a camera that focused an image through a lens onto an array of photoelectric cells coating the end of a tube. The electrical image formed by the cells would be scanned line-by-line by an electron beam and transmitted to a cathode-ray tube.

Rather than an electron beam, Farnsworth's image dissector device used an "anode finger" -- a pencil-sized tube with a small aperture at the top -- to scan the picture. Magnetic coils sprayed the electrons emitted from the electrical image left to right and line by line onto the aperture, where they became electric current. Both Zworykin's and Philo's devices then transmitted the current to a cathode-ray tube, which recreated the image by scanning it onto a fluorescent surface.

Farnsworth applied for a patent for his image dissector in 1927. The development of the television system was plagued by lack of money and by challenges to Farnsworth's patent from the giant Radio Corporation of America (RCA). In 1934, the British communications company British Gaumont bought a license from Farnsworth to make systems based on his designs. In 1939, the American company RCA did the same. Both companies had been developing television systems of their own and recognized Farnsworth as a competitor. World War II interrupted the development of television. When television broadcasts became a regular occurrence after the war, Farnsworth was not involved. Instead, he devoted his time to trying to perfect the devices he had designed.


David Sarnoff, vice president of the powerful Radio Corporation of America, later hired Zworykin to ensure that RCA would control television technology. ...


Television History - Invention of Television