A Thumbnail History of Electronics
Thomas Alva Edison (1847-1931) was owner or
co-owner of a record 1,093 patents. He also
invented the modern
industrial research laboratory. In 1882, when one of his engineers, William Hammer,
observed the "Edison Effect" during the course of experiments about the
incandescent lamp, Edison, for reasons which he could not later explain,
uncharacteristically did not follow up on the discovery. But, as he later admitted,
at the time he did not even understand Ohm's law. The Edison effect remained an
unexplained curiosity for fifteen years until the discovery of the electron.
John Ambrose Fleming (1849-1945) had a remarkable
career which spanned the first 
seventy-five years of the development of electronics.
Fleming was a student of Maxwell’s who later worked as a consultant for Edison and
then Marconi. In 1904, following Edison’s observation of the passage of current from
the filament to an anode in a light bulb and J.J. Thomson’s discovery that cathode
rays consisted of charged particles, Fleming invented and patented the first electronic
rectifier, the diode, or Fleming Valve. The device was intended for use in
detecting the spark-generated radio waves of the time, replacing the other devices used by
the pioneers of radio communication. Fleming was knighted in 1929.
(1873-1961), son of a Congregational
minister who was president of the Talledega College for Negroes in Alabama, lived a long
life full of controversy. He was defrauded by partners, was involved in numerous patent
suits, went through two divorces, and once was indicted (but later acquitted) for mail
fraud for seeking to sell a worthless device (his audion tube), De Forest held more than
300 patents but is most remembered for initiating the electronic revolution with his 1906
invention of the audion tube, a three-element vacuum tube in which the grid controlled the
current, which made modern radio possible. In 1912 he conceived the idea of
cascading triodes to achieve high amplification and also independently discovered
regenerative feedback.
General Electric Research Lab after a brief career in Academia. In
1911, he succeeded in fabricating a ductile form of tungsten which provided the filaments
for modern incandescent lamps and also patented a thoriated cathode with improved emission
for use in vacuum tubes. In 1913 Coolidge invented a hot-tungsten filament x-ray tube
which provided a more penetrating and reliable source for radiology. The "Coolidge
tube" became the standard generator of medical x-rays.
Schottky was Swiss, but he was educated and
spent his professional career in Germany. In 1919 he invented the first multiple grid
vacuum tube, the tetrode. Schottky obtained multiple doctoral degrees, taught at
universities from 1920 to 1927, and then worked for Siemans for nearly five decades. He
was the first to note the existence of "holes" in the band structure of
semiconductors, discovered the type of lattice vacancy known as the Schottky defect, and
in 1938 created a theory that explained rectification at a metal/semiconductor interface.
Irving Langmuir
(1881-1957), son of a struggling Brooklyn businessman, showed a precocious interest in
Science. He received his degrees in Chemistry, but, tiring of the endless round teaching
elementary courses and paper grading required of professors, left academia and went to the
General Electric Research Laboratory. His work on molecular films won the Nobel Prize in
Chemistry in 1932, and his studies on hot filaments in gases became the basis for
improvements in incandescent lighting and a huge industry. His discoveries about the
emission of electrons from cathodes and their behavior in vacuum tubes formed the
basis for the design of a variety of tube types.
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