Kálmán Tihanyi
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Kálmán Tihanyi (April 28, 1897 - February 26, 1947), was a Hungarian physicist, electrical engineer and inventor. His most important inventions concerning the design of the cathode ray tube, iconoscope, for television were bought and developed by RCA (Radio Corporation of America) and German companies Loewe and Fernseh AG.
He was born in Uzbeg, Hungary, studied electrical engineering and physics in Pozsony and Budapest.
He filed his first patent application for a his fully electronic television system on March 20, 1926. Though it may at first brush seem similar to some earlier proposals also employing the cathode-ray tube (Braun tube) for both transmitter and receiver, on closer examination we discover that the system Tihanyi described represents a radical departure. Like the final, improved version Tihanyi would patent in 1928, it embodied an entirely new concept in design and operation, building upon a phenomenon that would become known as the "storage principle". This involved the maintenance of photoemmission from the lightsensitive layer of the photoraster (the "eye" of the camera) between scannings. By this means the accumulation of positive charges would take place and the "latent electric picture" would be stored. This would mean an effective increase in the picture current by a factor that under ideal conditions would equal the number of picture elements (pixels). Tihanyi filed two separate patent applications in 1928 then extended patent protection beyond Germany, filing in France, England and the United States, among others.
In 1928, Tihanyi went to Berlin, where the development of television, that is, mechanical type of television involving Nipkow disks, had already begun by the German Post and the larger manufacturers. The invention was received with enthusiasm by Telefunken and Siemens, but in the end they opted to continue with the development of mechanical television.
RCA approached Tihanyi in 1930, after the publication of his patents in England and France. Negotiations continued until 1934, when RCA, ready to unveil its new television system based on Tihanyi's design, purchased his patents. These covered controlling features that the U.S. Patent Office patent examiners, citing Tihanyi's prior publications, had denied several key patent claims to Zworykin's 1930 - 31 pending applications. Tihanyi's U. S. patents, assigned to RCA, were issued to Tihanyi in 1938, respective 1939 with 1928 priority. Now it is becoming increasingly obvious that the originator of this pivotal invention was Kalman Tihanyi.
From 1929, Tihanyi worked on television-guidance for defense, building prototypes of a camera for robot aircraft in London for the British Air Ministry, later adapting it for the Italian Navy. In 1935-1940, he completed plans for an Acoustic Radiator -- with a planned projection range of up to 8 km -- and in 1940, he returned to Hungary where he built a full-scale prototype of the device.
