Vladimir Zworykin,

Born July 30, 1889 - Died July 29, 1982

Zworykin (one of Rosing's assistants, who had emigrated to the United States) invented the "lconoscope". 
This was a globe-shaped cathode-ray- tube and it contained the first photoelectric mosaic made from metal particles applied to both sides of a sheet of mica.

The first camera tube was more compact than the disc; easier to use and more sensitive. 
The electron beam, which "visits" the elements of the mosaic at a considerable speed, collects from each point all the photoelectric charge which has accumulated there since the last visit, whereas in the mechanical systems the photoelectric cell receives the light from each point only during the very short period while it is actually being scanned.

Zworykin presented the first prototype iconoscope at a meeting of engineers 
in New York in 1929. The apparatus was built by RCA in 1933.

It scanned the image in 120 lines, at 24 frames/second.

The iconoscope, invented in 1929 by the American Viadimir Zworykin, is the ancestor of all television camera tubes. The tube has a vacuum-tight glass envelope. At its centre is a dielectric plate (mica) one surface of which is coated with a thin uniform layer of metal, the other with a mosaic of thousands of tiny metal elements which release electrons under the effect of illumination. 
The scene is focused onto this mosaic, which makes up a series of mini-condensors. 
An electron beam bombards these, one after the other. The amount of charge collected is proportional to the charge on each condensor, and therefore to the strength of illumination of each element.

Most people think of television as a development of the mid-20th century. 

But as early as 1929 Russian inventor Vladimir Kosma Zworykin was demonstrating a system with all the features of modern picture tubes. 

Born in Murom, 200 miles east of Moscow, Zworykin at age nine started spending summers as an apprentice aboard the boats his father operated on, on the Oka River. 
He eagerly helped repair electrical equipment, and it soon became apparent that he was more interested in electricity than anything nautical. 
At the Imperial Institute of Technology, Boris Rosing, a professor in charge of laboratory projects, became friendly with the young student engineer and let him work on some of his private projects. 
Rosing was trying to transmit pictures by wire in his own physics laboratory. He and his young assistant experimented with a primitive cathode-ray tube, developed in Germany by Karl Ferdinand Braun. 

In 1910 Rosing exhibited a television system, using a mechanical scanner in the transmitter and the electronic Braun tube in the receiver. 
The lure of theoretical physics drew Zworykin to Paris after he graduated with honors and a scholarship in electrical engineering in 1912. 
There he studied X-rays under Paul Langevin. 

Arriving in the United States in 1919, he soon joined the staff at the Westinghouse laboratory in Pittsburgh. On November 18,1929, at a convention of radio engineers, Zworykin demonstrated a television receiver containing his 'kinescope':
A cathode-ray tube. 
That same year Zworykin joined the Radio Corporation of America (RCA) in Camden, New Jersey. 
As the director of their Electronic Research Laboratory, he was able to concentrate on making critical improvements to his system. Zworykin's 'storage principle' is the basis of modern TV.