The cathode ray tube or CRT, invented by German physicist Karl Ferdinand Braun, is the display device that was long used in most computer displays, video monitors, televisions, radar displays and oscilloscopes. The CRT developed from Philo Farnsworth's work was used in all television sets until the late 20th century and the advent of plasma screens, LCD TVs, DLP, OLED displays, and other technologies. As a result of CRT technology, television continues to be referred to as "the tube" well into the 21st century, even when referring to non-CRT sets.
