'Karl Ferdinand Braun' (
6 June 1850 in
Fulda,
Germany –
20 April 1918 in
New York City,
U.S.) was a
German inventor,
physicist and
Nobel Prize laureate.
Biography
Braun was educated at the
University of Marburg and received a Ph.D from the
University of Berlin in
1872. In
1874 he discovered that a point-contact
semiconductor rectifies alternating current. He became director of the Physical Institute and professor of
physics at the
University of Strasbourg in
1895.
In
1897 he built the first
cathode-ray tube oscilloscope. CRT technology is to this day used by most television sets and computer monitors. The
CRT is still called the "Braun tube" (''Braunsche Röhre'') in
German-speaking countries (and in Japan: ''Buraun-kan'').
During the
development of radio, he also worked on
wireless telegraphy. Around 1898, he invented a
crystal diode rectifier or
Cat's whisker diode.
Guglielmo Marconi used Braun's patents (among others). Braun's British patent on tuning was used by Marconi in many of his tuning patents. Marconi would later admit to Braun himself that he had "''borrowed''" portions of Braun's work. In
1909 Braun shared the
Nobel Prize for physics with Marconi for "contributions to the development of wireless telegraphy."
Braun went to the United States at the beginning of
World War I to help defend the German wireless station at
Sayville, N.Y. (on
Long Island) against attacks by the British controlled
Marconi Corporation. (At this time the U.S. had not yet entered the war). Braun died in his house in
Brooklyn (
New York City) before the war ended in 1918.
References
1. K.F. Braun: "On the current conduction in metal sulphides (title tranlated from German into English)", Ann. Phys. Chem., 153 (1874), 556. (In German)
2. Keller, Peter A.: The cathode-ray tube: technology, history, and applications. New York: Palisades Press, 1991. ISBN 0-9631559-0-3.
3. Keller, Peter A.: "The 100th Anniversary of the Cathode-Ray Tube," Information Display, Vol. 13, No. 10, 1997, pp. 28-32.
See also
★ ''
Radio'':
History of radio,
Invention of radio
★ ''People'':
Edouard Branly
External articles and references
;Patent
★
★
;Other
★ "''
Ferdinand Braun – Biography''". Nobel Lectures. Physics 1901-1921, Elsevier Publishing Company, Amsterdam, 1967.
★ Naughton, Russell, "''
Karl Ferdinand Braun, Dr : 1850 - 1918''".
★ "''
Karl Ferdinand Braun ''". Biographies of Famous Electrochemists and Physicists Contributed to Understanding of Electricity.
★ Rybak, James P., "''Forgotten" Pioneers of Wireless;
Part 5 - Karl Ferdinand Braun''".
★ "''
Karl Ferdinand Braun, 1850-1918''". (German) (
English translation)
★
The Ferdinand-Braun-Institut fuer Hoechstfrequenztechnik Berlin, Germany