Editing Opto-isolator (section)

==History==
The value of optically coupling a solid state light emitter to a semiconductor detector for the purpose of electrical isolation was recognized in 1963 by Akmenkalns, et al. (US patent 3,417,249). Photoresistor-based opto-isolators were introduced in 1968. They are the slowest, but also the most [[linear#Electronics|linear]] isolators and still retain a niche market in the audio and music industries. Commercialization of LED technology in 1968–1970 caused a boom in [[optoelectronics]], and by the end of the 1970s the industry developed all principal types of opto-isolators. The majority of opto-isolators on the market use bipolar silicon phototransistor sensors.<ref>Graf, p. 522; PerkinElmer, p. 28.</ref> They attain medium data transfer speed, sufficient for applications like [[electroencephalography]].<ref name=ANA>See Ananthi, pp. 56, 62 for a practical example of an opto-coupled EEG application.</ref> The fastest opto-isolators use [[PIN diode]]s in [[photodiode#Photoconductive mode|photoconductive mode]].