Karl Ferdinand Braun

Karl Ferdinand Braun, a German applied physicist born in 1850 and died in 1918, is remembered in media history chiefly for inventing the cathode ray tube in 1897, the vacuum tube display device that became the basis of television picture tubes for most of the twentieth century. Braun also developed an early semiconductor point contact diode in 1874 and, working on wireless telegraphy, created a phased array antenna and a two circuit tuned transmission system that improved the range and selectivity of early radio. For these contributions to wireless telegraphy he shared the 1909 Nobel Prize in Physics with Guglielmo Marconi. He later co-founded the wireless equipment firm Telefunken, and his cathode ray tube work has led some historians to call him a father of television.