History of hearing aids
The development of transistors in 1948 by Bell Laboratories led to major improvements to the hearing aid. The transistor was invented by John Bardeen, Walter Brattain, and William Shockley. Transistors were created to replace vacuum tubes; they were small, required less battery power and had less distortion and heat than their predecessor. These vacuum tubes were typically hot and fragile, so the transistor was the ideal replacement.The 1952 Sonotone 1010 used a transistor stage along with vacuum tubes, to extend battery life. The size of these transistors led to developments in miniature, carbon microphones. These microphones could be mounted on various items, even eyeglasses. In 1951, Raytheon manufactured the transistor and was one of the first companies to mass-produce transistors to throughout America. Raytheon realized that their hearing aid only lasted short-term and began to sell the vacuum-tube hearing aids again along with transistor hearing aids.
Walter Houser Brattain
On December 23, 1947, Walter Brattain, John Bardeen, and William B. Shockley demonstrated the first working transistor to their colleagues at Bell Laboratories. Amplifying small electrical signals and supporting the processing of digital information, the transistor is "the key enabler of modern electronics". The three men received the Nobel Prize in Physics in 1956 "for research on semiconductors and the discovery of the transistor effect."