De Forest, Lee
Lee de Forest (1873 – 1961), an American inventor who devised the first vacuum tube, a device that amplifies weak electrical signals. (Another main contributor to this field was John Fleming, see Fleming, John Ambrose.) De Forest’s Audion was a three-element tube, generally known as a triode, a type of vacuum tube (or gas-filled tube) with three elements: the filament or cathode, the grid, and the plate. A small amount of power applied to the grid could control a much larger current flowing from the filament to the plate, allowing the Audion to amplify radio signals by placing the weak signal from the radio antenna on the grid, with a larger current from a battery between the filament and plate. The Audion made practical radio broadcasts a reality. By the 1920s, "tube radios" were a fixture of most western households and remained so until the introduction of the transistor radio in the 1950s. For this contribution, de Forest is viewed as one of the fathers of the "electronic age," as the Audion helped to usher in the widespread use of electronics.
Further Reading
Lee de Forest - Biography (Hebrew University of Jerusalem, Institute of Chemistry)
Lee de Forest - Biography (PBS Online)
