HISTORY OF ELECTRONICS
The early history of electronics is closely tied to experimentation with the Crookes tube, a type of vacuum tube developed by Sir William Crookes, an English physicist and chemist. While performing experiments with a Crookes tube, Wilhelm Konrad Roentgen, a German physicist, discovered X rays in 1895. In 1897, Ferdinand Braun, another Germany physicist modified the Crookes tube to make the first oscilloscope, an instrument that produces a visual image of an electric signal.
Interest in improving the reception of radio waves led to the invention of the vacuum-tube diode in 1904 by Sir John Fleming, an English electrical engineer, and to the invention of the vacuum-tube triode in 1907 by Lee De Forest, a United States inventor. The invention of the triode was a key event in the history of electronics, since it was the first electronic amplifier.
During World War I there was an increased interest in developing radio and electronics, and by 1920 the development of vacuum tubes and circuits employing them had advanced to the point where their superiority over all other devices used in radio transmitters and receivers was apparent. Regular commercial radio broadcasting in the United States began in 1920, and the demand for household receivers soon made electronics an important industry.
Certain technical limitations in the operation of electron tubes were overcome with the development of the pentode in 1929. The advances being made at this time helped lead to the development of television; the first regular television broadcasting began in 1936, in London.
During World War II, emphasis was placed on the development of electronics for military use. Radar was greatly improved and in 1944 the first large electronic digital computer, ENIAC, was built. The main purpose of the computer was to speed up the calculation of tables of data for aiming artillery. The electronics industry emerged from the war as a major industry. Its growth following the war continued as television manufacturing entered a boom period and military programs demanded more advanced electronic technology.
In 1948 William Shockley, John Bardeen, and Walter H. Brattain of Bell Telephone Laboratories developed the first transistor, a forerunner of the bipolar junction transistor. During the early 1950's the technology was developed to mass-produce transistors. The advantage of semiconductor devices over electron tubes created a demand for techniques to further reduce the amount of space required for electronic components. An important step toward miniaturizing electronic components was the introduction of the integrated circuit in the early 1960's. The techniques necessary to fabricate such circuits were pioneered by Jack Kirby of Texas Instruments in 1959.
During the 1970's and 1980's the size of the components of integrated circuits continued to be reduced and the number of components that could be produced on each chip grew rapidly. With increasing miniaturization, the capabilities of the electronic circuits and the speed at which they could perform their functions greatly increased. Each advance helped reduce the cost of producing electronic products.
Through the 1980's and into the 1990's, the variety of products being built with electronic components increased, and the use of electronic control devices led to greater automation. Microelectronics led to the development of new technologies, such as digital audio recording; to the introduction of new products, such as personal computers; and to the reduction in the size of portable telephones and many other electronic products.