Bell invented the telephone in March 1876 10. The American inventor Bell invented the world's first telephone and obtained the telephone patent approved by the US Patent Office.
Alexander Graham Bell, born in Edinburgh, England, graduated from University College London, and is a famous inventor and entrepreneur in Scotland. He applied for the patent of the world's first telephone and founded Bell Telephone Company.
The development history of telephone:
Bell applied for the telephone patent in March 1876. Carbon microphone appeared in 1878, which greatly improved the efficiency of telephone microphone. 1880 * * electric telephone appeared, which was powered by * * * electric switch in a centralized way, saving the hand-broadcast generator and dry battery.
189 1 year, rotary dial-up automatic telephone appeared, which can send out DC dial-up pulse, control the action of automatic exchange, select the called user and automatically complete the transfer function. Thus pushing telephone communication to a new stage.