Tech History Made on March 12, 1923

On this day in 1923 movies received synchronized sound. Many had tried and failed to sync the human voice with moving lips on screen. Thomas Edison tried using a phonograph in conjunction with a moving picture, it didn't work. Lee de Forest bypassed the phonograph and combined the sound and pictures. He placed the sound recording on the film using an optical soundtrack. Sound frequency and volume were analog blips of light on the film. Forests patents dated back to 1919 but his first successful try was during a press demo in 1923. His technique was used for years until digital sound in the 1990's. The Oscars honored him 1959 with a special award for the "pioneer invention which brought sound to the motion picture".