ABSTRACT
The technology used to transmit, treat and record large volumes of information with the aid of light is referred to as optoelectronics. Using new materials light has become controllable and can be transmitted faster and further with great reliability. Further improvements can be expected to result from the development of new materials and by improvements in manufacturing processes. Optical memory materials record and store information by reacting under light irradiation and then can release it when required. Photographic films are the best-known example of such materials. Some materials generate light having a wavelength of one-half or one-third that of the incident light wavelength. Other materials increase the incident wavelength by a factor of two or three. Single crystals of nonlinear optical materials have been grown either from the vapour, solution or melt phases. Inorganic materials are generally grown from the melt, although solution growth is also used for materials having good solvents.
