De Forrester was a prolific inventor, who obtained more than 3 patents in his life. In addition to the electron tube, his inventions also include the technology of recording sound on the edge of film, high-frequency electrothermal physiotherapy machine used in medicine and so on. He failed repeatedly in business, and his technological inventions did not bring him any economic benefits. Many important patents were sold to AT&T at low prices. T), even the patent of the electron tube amplifier only sold for $39,. However, his invention also won him the titles of "father of radio", "father of television" and "father of electron tube".
Electron tubes are mainly used in radio devices, and their birth paved the way for the development of communication, broadcasting, television and other technologies. However, it was soon discovered that the vacuum triode can be used as a switching device in addition to the amplification state, and its speed is thousands of times faster than that of the relay. Electron tubes were quickly favored by computer developers, and computer history entered the era of electronics because of deforest.