AVS 51st International Symposium
    Vacuum Technology Tuesday Sessions
       Session VT-TuA

Invited Paper VT-TuA1
John Ambrose Fleming and the Beginning of Electronics

Tuesday, November 16, 2004, 1:20 pm, Room 303D

Session: Special Session at the 51st International AVS Symposium: "Fleming Centenary Session: The Birth and Evolution of Electronics"
Presenter: H.F. Dylla, Jefferson Laboratory
Correspondent: Click to Email
This year is the centenary of John Ambrose Fleming’s momentous patent on the thermionic diode that was the birth of electronics. The "Edison effect" was discovered in 1882, this was later shown to be the result of thermionic emission of electrons from a heated filament into a vacuum. Edison did not make any significant devices based on this discovery and the effect was ignored for more that 8 years. In 1890 Fleming explained the effect and showed that the thermionic diode could be used as a rectifier. Fourteen years later Fleming filed this momentous 1904 patent on the thermionic diode that was the first public announcement of the electron tube; this revolutionized the development of radio and led to the invention of the thermionic triode by Lee de Forest in 1906. The background to these events will be described.