Other Free Encyclopedias » Online Encyclopedia » Encyclopedia - Featured Articles » Contributed Topics from U-Z

Zworykin, Vladimir (Kosma)

screen developed television system

[ tsvo rikin] (1889–1982) Russian–US physicist: invented the electronic-scanning television camera.

Soon after graduating in engineering from St Petersburg Institute of Technology, Zworykin spent the First World War serving as a radio officer in the Russian army. One of his teachers in St Petersburg was B Rosing, who took out the first patent for a television system in 1907; it used a cathode-ray tube as its receiver. After Russia’s collapse into revolution in 1917 Zworykin emigrated to America in 1919 and joined the Westinghouse Electric Corporation. His career developed as he gained a doctorate (1926) and moved to a post with the Radio Corporation of America (1929).

While at Westinghouse in 1923 he reproduced an image from a screen by dividing it into many insulated photoelectric cells, which held a charge proportional to the light falling on them. An electron beam scanning the screen discharged the cells in turn, giving an electrical signal.

Zworykin then took a cathode-ray tube (invented in 1897), which could produce focused spots on its fluorescent screen using electric and magnetic fields. As the beam scanned the screen the intensity of the spot varied according to the electrical signal and so could reproduce the images from his first device, so that he had a television transmitting and receiving system. By 1929 the camera had been developed to the point of practical use, and it displaced the mechanical system developed.

[back] Zuma Beach

User Comments

Your email address will be altered so spam harvesting bots can't read it easily.
Hide my email completely instead?

Cancel or