OPTOELECTRONIC DEVICE

any device in which the photon, the basic particle of light, is affected. Such devices can be divided into four groups: (1) photodetectors and solar cells that convert photons into electrical current, (2) light-emitting diodes and semiconductor lasers that convert an applied voltage into emitted photons, (3) optical fibres that guide light within a small plastic or glass fibre between a light source and a detector, and (4) optical-fibre amplifiers that convert the energy of an optical pump source to photons identical to an optical signal. A useful expression when dealing with optoelectronics is the conversion between the wavelength of the light, l, in micrometres, and the energy of the photon, E, in electron volts: l = 1.24/E. Additional reading Several optoelectronic devices are discussed in S.M. Sze, Physics of Semiconductor Devices, 2nd ed. (1981), especially chapters 1214; and Pallab Bhattacharya, Semiconductor Optoelectronic Devices (1994). Works on specific devices include, on photodetectors, G.E. Stillman, V.M. Robbins, and N. Tabatabaie, III-V Compound Semiconductor Devices: Optical Detectors, in IEEE Transactions on Electron Devices, ED-31(11):16431655 (November 1984); and R.K. Willardson and Albert C. Beer (eds.), Infrared Detectors II (1977); on solar cells, Harold J. Hovel (ed.), Solar Cells, vol. 11 of Semiconductors and Semimetals (1975); and Institute of Electrical and Electronic Engineers, The Conference Record of the Nineteenth IEEE Photovoltaic Specialists Conference1987 (1987); on light-emitting diodes, M.G. Craford, LEDs Challenge the Incandescents, IEEE Circuits and Devices Magazine, 8(5):2429 (September 1992); and Stan Gage et al., Optoelectronics/Fiber-Optics Applications Manual, 2nd ed. (1981); on lasers, G.P. Agrawal and N.K. Dutta, Long-Wavelength Semiconductor Lasers (1986); H.C. Casey, Jr., and M.B. Panish, Heterostructure Lasers, 2 vol. (1978); W.T. Tsang (ed.), Lightwave Communications Technology, part C, Semiconductor Injection Lasers II, Light Emitting Diodes (1985); and D.F. Welch, Coherent Lasers Turn Up the Power, IEEE Circuits and Devices Magazine, 8(5):1723 (September 1992); on optical fibres, Tatsuya Kimura, Factors Affecting Fiber-Optic Transmission Quality, Journal of Lightwave Technology, 6(5):611619 (May 1988); Stewart E. Miller and Alan G. Chynoweth, Optical Fiber Telecommunications (1979); and John M. Senior, Optical Fiber Communications: Principles and Practice, 2nd ed. (1992); on erbium-doped optical-fibre amplifiers, Emmanuel Desurvire, Lightwave Communications: The Fifth Generation, Scientific American, 266(1):114121 (January 1992); and, on liquid-crystal displays, E. Kaneko, Liquid Crystal TV Displays: Principles and Applications of Liquid Crystal Displays (1987); Terry Scheffer and Jrgen Nehring, Supertwisted-Nematic (STN) LCDs, Seminar Lecture Notes, 1:M-7/163 (May 1993), published by the Society for Information Display; J.W. Goodby et al., Ferroelectric Liquid Crystals: Principles, Properties, and Applications (1991); and Birendra Bahadur (ed.), Liquid Crystals: Applications and Uses (1990 ). H. Craig Casey, Jr. Terry J. Scheffer