The article focuses on the career of Lee de Forest, inventor of the Audion thermionic valve and the Phonofilm sound on film system. De Forest, born in Iowa, developed an improved wireless telegraph receiver in 1899 and founded De Forest Wireless Telegraph Co. In 1905, he worked with Edison's lamps and founded "The Audion" which was granted a patent in January 1907. He received several awards including the recognition of the Audion's contribution to French military communications.