Kenjiro Takayanagi among World’s Premier Innovators
In Japan, Hamamatsu Industrial High School, Waseda University, and other institutions began studies on television at the end of the Taisho era. It is said that Kenjiro Takayanagi became determined to work on television when he saw a picture in a French magazine illustrating a future television.
Kenjiro Takayanagi (1899-1990) had already begun studies on a television set using an electric device for both imaging and image reception by 1925. Later, due to the technical and experimental conditions, Takayanagi constructed a system that utilized a mechanical Nipkow disk and a photoelectric tube in the transmitting device, and an electric Braun tube in the receiving device. He succeeded in displaying a clear image of the character “” on a Braun tube on December 25, 1926 (on a mechanical and electrical system with 40 scanning lines). His research progressed to the successful experimental TV transmission of an image of a person in 1928 (40 scanning lines, 14 frames/second)
In 1930, at the 5th anniversary exhibition of radio broadcasting, two TV systems, one from Hamamatsu Industrial High School and one from Waseda University, were demonstrated and experiments conducted. The experiment by Professors Tadaoki Yamamoto and Masataro Kawarada of Waseda University gained favorable comments with its 60 scanning line, 125 frames per second resolution image projected on a five-foot square display.
All-electric TV System Completed
The NHK Science & Technical Research Laboratories, which was established in 1930, also initiated research on television around this time. Takayanagi successfully conducted a TV experiment with a 100 scanning line, 20 frames per second system, and Tokyo Denki K.K. conducted an experiment using a 120 scanning line system employing a Farnsworth tube.
This was followed by the invention of an image pickup tube iconoscope by Zworykin of the United States in 1931, a development which shocked the world. Immediately afterwards, Takayanagi’s team test manufactured an iconoscope by themselves (220 scanning lines, 20 frames/second), and completed an all-electric TV system with 245 scanning lines, interlaced scanning, and 30 frames per second transmission. Further improvements were made by Takayanagi’s team, and in 1937, they fabricated TV set with 441 scanning lines at 30 frames per second, which at the time was the world’s best and is almost equivalent to the present TV system. In 1939, NEC and Toshiba developed the first domestic TV set.
Resolution Focus of Global Competition in the 1930s
The 1930s saw preparations for implementing TV broadcasting in Europe. This was especially true in Germany, where preparations for broadcast of the 1936 Berlin Olympics had been mandated with a government initiative and the claim that the country’s prestige was at stake. Experimental TV broadcasting first started in March 1935 in Germany, with a 180 scanning line system (increased to 441 scanning lines in 1937). France also launched a test broadcast using the same 180 scanning line system in April of the same year. The first regular TV broadcasting in the world originated in Britain and employed the epoch-making 405 scanning line system. In Japan, the Television Research Committee adopted a provisional standard of a 441 scanning line, 25 frames per second, interlaced scanning system in 1938. 1. Milestones of great Japanese |
Reproduction of character “”
(NHK Broadcasting Museum)
Takayanagi lectures on TV at the National Science Museum
(The National Science Museum)
Takayanagi (second from left) with an image-transmitting device at an exhibition in 1930 (Hamamatsu Electronics Promotion Association)
Waseda University TV system experiment (1933)
Image from an early Waseda University TV system (Wyler mirror is used in the receiving set)
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