 In 1906, Lee De Forest of the US added a control "grid" to the valve to create an amplifying vacuum tube RF detector called the "Audion", leading Fleming to accuse him of infringing his patents.De Forest's tube developed into the triode the first electronic amplifier.The triode was vital in the creation of long-distance telephone and radio communications, radars, and early electronic digital computers (mechanical and electro-mechanical digital computers already existed using different technology).