Invention
The first three-element device (mercury-vapor filled with a control grid) was patented on March 4 1906 by the Austrian Robert von Lieben independent from that, on October 25 1906 Lee De Forest patented his two-element Audion. The original Audion did not provide amplification. However it was not until around 1912 that other researchers, while attempting to improve the service life of the Audion, stumbled on the principle of the true vacuum tube. The name triode appeared later, when it became necessary to distinguish it from other generic kinds of vacuum tubes with more or fewer elements (e.g. diodes, tetrodes, pentodes, etc.). The Audion tubes deliberately contained some gas at low pressure. The name triode is only applied to vacuum tubes which have been evacuated of as much gas as possible.
There was a lengthy lawsuit between von Lieben and De Forest.
Read more about this topic: Triode
Famous quotes containing the word invention:
“In all her products, Nature only develops her simplest germs. One would say that it was no great stretch of invention to create birds. The hawk which now takes his flight over the top of the wood was at first, perchance, only a leaf which fluttered in its aisles. From rustling leaves she came in the course of ages to the loftier flight and clear carol of the bird.”
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