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.

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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Prism may refer to:

Science and mathematics

• Prism (optics), a transparent object which refracts light
• Dispersive prism, the most familiar type of optical prism
• Prism (geometry), a kind of polyhedron
• Prism (geology), a kind of sedimentary rock

Media and entertainment

Books, comics and magazines

• Prism (comics), a Marvel Comics character
• Prism (fictional planet), a fictional world depicted in the books of Alan Dean Foster
• Prism magazine (New Zealand), a Christian periodical

Music

• Prism (band), a Canadian rock band
• Prism (album), the debut album of the Canadian band
• Prism (Japanese band), a jazz fusion band
• Prism (Jeff Scott Soto album)
• Prism Records, a record label

Other

• PRISM (TV channel), a defunct television service in Philadelphia

Computing and software

• PRISM (chipset), a wireless networking chipset
• Apollo PRISM, a microprocessor made by Apollo Computer
• DEC PRISM, a microprocessor made by Digital Equipment Corporation
• Mozilla Prism, a software product for desktop integration of web applications
• SGI Prism, a computer
• IBM's PR/SM - a mainframe hypervisor

Education

• PRISM (Portal Resources for Indiana Science and Mathematics), a website for teachers
• A program for gifted children in Bellevue, Washington and Thomas Grover Middle School, New Jersey

Other meanings

• Nokia Prism, a fashion mobile phone collection
• Oregon Performance Reporting Information System, a state agency
• Prism Micro Products, a British telecommunications company