SCIENCE PHOTO LIBRARY SCIENCE PHOTO LIBRARY
Lee De Forest. Portrait of American physicist, engineer and radio pioneer Lee De Forest (1873- 1961). He is holding a phonofilm motion picture camera. This camera, which he invented in 1920, was used in the first film with sound, The Jazz Singer, in 1926. De Forest gained his doctorate at Yale University, USA, with a thesis on radio waves. In 1907 he patented the Audion tube, a thermionic triode valve. This adapted diode had a third electrode between the cathode and anode. The triode amplified weak signals, allowing the practical development of radio broadcasting and the first computers. Triodes were eventually replaced by solid-state devices.
Model release not available. Property release not required.