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==Origin==
Post-classical [[Latin]] prisma solid geometrical figure (5th cent.) < ancient [[Greek]] πρῖσμα sawdust, in Hellenistic Greek also (in [[geometry]]) prism (Euclid) < πρίζειν to saw or something sawed rare [[parallel]] form to πρίειν
*[http://en.wikipedia.org/wiki/16th_century 1570]
==Definitions==
*1. ''[[Geometry]]'': A solid figure with two end [[faces]] that are similar, [[equal]], and [[parallel]] rectilinear figures, and whose sides are parallelograms or rectangles.
*2. ''[[Optics]]'': A [[transparent]] object in the [[form]] of a geometrical prism; esp. a right prism whose ends are [[identical]] acute-angled triangles, used for [[refracting]] [[light]] that passes through the sides.
*3. A [[spectrum]] as produced by [[refraction]] through a prism. In pl.: prismatic [[colors]].
==Description==
In [[optics]], a '''prism''' is a [[transparent]] optical element with flat, polished [[surfaces]] that [[refract]] [[light]]. The exact [[angles]] between the surfaces depend on the [[application]]. The [[traditional]] geometrical shape is that of a triangular prism with a triangular base and rectangular sides, and in colloquial use "prism" usually refers to this type. Some types of optical prism are not in [[fact]] in the shape of geometric prisms. Prisms are typically made out of glass, but can be made from any [[material]] that is [[transparent]] to the [[wavelengths]] for which they are [[designed]].
A prism can be used to break [[light]] up into its constituent [[spectral]] [[colors]] (the colors of the rainbow). Prisms can also be used to [[reflect]] [[light]], or to split light into components with [[different]] polarizations.
In [http://en.wikipedia.org/wiki/Isaac_Newton Isaac Newton]'s time, it was believed that white [[light]] was colorless, and that the prism itself produced the [[color]]. Newton's [[experiments]] convinced him that all the colors already existed in the [[light]] in a [[heterogeneous]] fashion, and that "corpuscles" ([[particles]]) of light were fanned out because particles with different colors traveled with [[different]] [[speeds]] through the prism. It was only later that [http://en.wikipedia.org/wiki/Thomas_Young_(scientist) Young] and [http://en.wikipedia.org/wiki/Augustin-Jean_Fresnel Fresnel] combined Newton's particle [[theory]] with Huygen's wave theory to show that color is the visible [[manifestation]] of [[light]]'s [[wavelength]].
Newton arrived at his conclusion by passing the red color from one prism through a second prism and found the color unchanged. From this, he concluded that the colors must already be present in the incoming [[light]] — thus, the prism did not create [[colors]], but merely separated colors that are already there. He also used a lens and a second prism to recompose the [[spectrum]] back into white [[light]]. This [[experiment]] has become a [[classic]] example of the [[methodology]] introduced during the [http://en.wikipedia.org/wiki/Scientific_revolution scientific revolution]. The results of this [[experiment]] dramatically [[transformed]] the field of [[metaphysics]], leading to [http://en.wikipedia.org/wiki/John_Locke John Locke]'s primary vs secondary [[quality]] distinction.
[http://en.wikipedia.org/wiki/Isaac_Newton Isaac Newton] discussed prism [[dispersion]] in great detail in his [[book]] ''[http://en.wikipedia.org/wiki/Opticks Opticks]''. He also introduced the use of more than one prism to [[control]] [[dispersion]]. Newton's description of his [[experiments]] on prism dispersion was [[qualitative]], and is quite readable. A [[quantitative]] description of [http://en.wikipedia.org/wiki/Multiple-prism_dispersion_theory multiple-prism dispersion] was not needed until multiple prism laser beam expanders were introduced in the 1980s.[http://en.wikipedia.org/wiki/Prism_%28optics%29]
[[Category: Physics]]
==Origin==
Post-classical [[Latin]] prisma solid geometrical figure (5th cent.) < ancient [[Greek]] πρῖσμα sawdust, in Hellenistic Greek also (in [[geometry]]) prism (Euclid) < πρίζειν to saw or something sawed rare [[parallel]] form to πρίειν
*[http://en.wikipedia.org/wiki/16th_century 1570]
==Definitions==
*1. ''[[Geometry]]'': A solid figure with two end [[faces]] that are similar, [[equal]], and [[parallel]] rectilinear figures, and whose sides are parallelograms or rectangles.
*2. ''[[Optics]]'': A [[transparent]] object in the [[form]] of a geometrical prism; esp. a right prism whose ends are [[identical]] acute-angled triangles, used for [[refracting]] [[light]] that passes through the sides.
*3. A [[spectrum]] as produced by [[refraction]] through a prism. In pl.: prismatic [[colors]].
==Description==
In [[optics]], a '''prism''' is a [[transparent]] optical element with flat, polished [[surfaces]] that [[refract]] [[light]]. The exact [[angles]] between the surfaces depend on the [[application]]. The [[traditional]] geometrical shape is that of a triangular prism with a triangular base and rectangular sides, and in colloquial use "prism" usually refers to this type. Some types of optical prism are not in [[fact]] in the shape of geometric prisms. Prisms are typically made out of glass, but can be made from any [[material]] that is [[transparent]] to the [[wavelengths]] for which they are [[designed]].
A prism can be used to break [[light]] up into its constituent [[spectral]] [[colors]] (the colors of the rainbow). Prisms can also be used to [[reflect]] [[light]], or to split light into components with [[different]] polarizations.
In [http://en.wikipedia.org/wiki/Isaac_Newton Isaac Newton]'s time, it was believed that white [[light]] was colorless, and that the prism itself produced the [[color]]. Newton's [[experiments]] convinced him that all the colors already existed in the [[light]] in a [[heterogeneous]] fashion, and that "corpuscles" ([[particles]]) of light were fanned out because particles with different colors traveled with [[different]] [[speeds]] through the prism. It was only later that [http://en.wikipedia.org/wiki/Thomas_Young_(scientist) Young] and [http://en.wikipedia.org/wiki/Augustin-Jean_Fresnel Fresnel] combined Newton's particle [[theory]] with Huygen's wave theory to show that color is the visible [[manifestation]] of [[light]]'s [[wavelength]].
Newton arrived at his conclusion by passing the red color from one prism through a second prism and found the color unchanged. From this, he concluded that the colors must already be present in the incoming [[light]] — thus, the prism did not create [[colors]], but merely separated colors that are already there. He also used a lens and a second prism to recompose the [[spectrum]] back into white [[light]]. This [[experiment]] has become a [[classic]] example of the [[methodology]] introduced during the [http://en.wikipedia.org/wiki/Scientific_revolution scientific revolution]. The results of this [[experiment]] dramatically [[transformed]] the field of [[metaphysics]], leading to [http://en.wikipedia.org/wiki/John_Locke John Locke]'s primary vs secondary [[quality]] distinction.
[http://en.wikipedia.org/wiki/Isaac_Newton Isaac Newton] discussed prism [[dispersion]] in great detail in his [[book]] ''[http://en.wikipedia.org/wiki/Opticks Opticks]''. He also introduced the use of more than one prism to [[control]] [[dispersion]]. Newton's description of his [[experiments]] on prism dispersion was [[qualitative]], and is quite readable. A [[quantitative]] description of [http://en.wikipedia.org/wiki/Multiple-prism_dispersion_theory multiple-prism dispersion] was not needed until multiple prism laser beam expanders were introduced in the 1980s.[http://en.wikipedia.org/wiki/Prism_%28optics%29]
[[Category: Physics]]
