prism

prism, in optics, a piece of translucent glass or crystal used to form a spectrum of light separated according to colors. Its cross section is usually triangular. The light becomes separated because different wavelengths or frequencies are refracted (bent) by different amounts as they enter the prism obliquely and again as they leave it (see refraction). The shorter wavelengths, toward the blue or violet end of the spectrum, are refracted by the greatest amount; the longer wavelengths, toward the red end, are refracted the least. The Nicol prism is a special type of prism made of calcite; it is used for polarization of light.

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prism

Piece of glass or other transparent material cut with precise angles and plane faces. Prisms are useful for analyzing and refracting light (see refraction). A triangular prism can separate white light into its constituent colours by refracting each different wavelength of light by a different amount. The longer wavelengths (those at the red end of the spectrum) are bent the least, the shorter ones (those at the violet end) the most. The result is the spectrum of visible light, or the rainbow. Prisms are used in certain kinds of spectroscopy and in various optical systems.

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(1) (PhotoRefractive Information Storage Materials Consortium) A collaboration of IBM, Stanford University, GTE, Hughes Research Labs, Optitek, SRI International and Rockwell Science Center that is funded by the U.S. government's Advanced Research Projects Agency for the purpose of researching holographic storage.

(2) (PRogrammable Integrated Scripts for Mirror) The programming language for the Mirror communications programs.

(3) See PR/SM.

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PRISM - A distributed logic language. ["PRISM: A Parallel Inference System for Problem Solving", S. Kasif et al, Proc 1983 Logic Prog Workshop, pp. 123-152].