prism

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prism,

in optics, a piece of translucent glass or crystal used to form a spectrumspectrum,
arrangement or display of light or other form of radiation separated according to wavelength, frequency, energy, or some other property. Beams of charged particles can be separated into a spectrum according to mass in a mass spectrometer (see mass spectrograph).
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 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 refractionrefraction,
in physics, deflection of a wave on passing obliquely from one transparent medium into a second medium in which its speed is different, as the passage of a light ray from air into glass.
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). 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 prismNicol prism
, optical device invented (1828) by William Nicol of Edinburgh. It consists essentially of a crystal of calcite, or Iceland spar, that is cut at an angle into two equal pieces and joined together again with Canada balsam.
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 is a special type of prism made of calcite; it is used for polarization of lightpolarization of light,
orientation of the vibration pattern of light waves in a singular plane. Characteristics of Polarization

Polarization is a phenomenon peculiar to transverse waves, i.e.
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.
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Prism

A geometric solid with regular polygons at its ends and parallelograms on its sides connecting the ends.
Illustrated Dictionary of Architecture Copyright © 2012, 2002, 1998 by The McGraw-Hill Companies, Inc. All rights reserved
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Prism

 

a polyhedron in which two of the faces are n-gons (the bases of the prism) and the remaining n faces (the lateral faces) are parallelograms. The bases of a prism are congruent and lie in parallel planes.

Figure 1

A prism is called a right prism if the lateral edges are perpendicular to the bases. A right prism is regular if each base is a regular polygon. Prisms can be triangular, quadrangular, and so on, depending on whether the bases are triangles, quadrilaterals, and so on. Figure 1 illustrates a hexagonal prism (the one on the left is also a right prism). The volume of a prism is equal to the product of the base and the altitude (the distance between the bases). See also.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.

prism

[′priz·əm]
(crystallography)
A crystal which has three, four, six, eight, or twelve faces, with the face intersection edges parallel, and which is open only at the two ends of the axis parallel to the intersection edges.
(geology)
A long, narrow, wedge-shaped sedimentary body with a width-thickness ratio greater than 5 to 1 but less than 50 to 1.
(mathematics)
A polyhedron with two parallel, congruent faces and all other faces parallelograms.
(optics)
An optical system consisting of two or more usually plane surfaces of a transparent solid or embedded liquid at an angle with each other. Also known as optical prism.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

prism

1. a transparent polygonal solid, often having triangular ends and rectangular sides, for dispersing light into a spectrum or for reflecting and deviating light. They are used in spectroscopes, binoculars, periscopes, etc.
2. a form of crystal with faces parallel to the vertical axis
3. Maths a polyhedron having parallel, polygonal, and congruent bases and sides that are parallelograms
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005

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].
This article is provided by FOLDOC - Free Online Dictionary of Computing (foldoc.org)

PRISM

(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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References in periodicals archive ?
Previous reports observed few or no alterations on enamel integrity after bleaching, (18) whereas a number of studies have described the effects of bleaching as morphological defects and the demineralization of enamel prisms. (9-12) Enamel mineral loss due to a significant decrease in calcium and phosphate content may occur after bleaching (13) which may even increase enamel susceptibility towards demineralization.
The research team compared proline repeats in amphibian and animal models and discovered that when the repeats are short, such as in frogs, teeth will not have the enamel prisms that are responsible for the strength of human enamel.
-- Enamel prisms are anchored at the enamel-dentine junction and extend to the occlusal surface with differing orientations characteristic of different taxa (Koenigswald, 1982; Boyde et al., 1988).
The tooth surface after exposure to orange juice appeared to affect the enamel prisms being exposed and this was visible at all the three magnifications (Figure-2).
This technique has claimed to improve fragment retention since enamel beveling alters the enamel prisms orientation, allowing for achievement of a more effective acid etching pattern.