Fresnel rhomb: Difference between revisions

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A Fresnel rhomb is a prism-like device designed in 1817 by Augustin-Jean Fresnel for producing circularly polarized light. However, in contrast to a wave plate, the rhomb does not utilise birefringent properties of the material.

The rhomb (usually a right-parallelepiped) is shaped such that light entering one of the small faces is internally reflected twice: once from each of the two sloped faces before exiting through the other small face. The angle of internal reflection is the same in each case, and each reflection produces a 45° (π/4 radians) phase delay between the two linearly polarized components of the light. Hence on the first reflection, a linearly polarized beam will be elliptically polarized, and will emerge as circularly polarized on the second reflection.

For visible light and a glass rhomb (refractive index n ≈ 1.5), an internal reflection angle of incidence of 48° or 54.6° is required.

External link and references

Hecht, E. (1987). Optics: Second Edition. Massachusetts: Addison-Wesley Publishing Company, Inc. ISBN 0-201-11611-1
http://physics.kenyon.edu/EarlyApparatus/Polarized_Light/Fresnels_Rhomb/Fresnels_Rhomb.html

This optics-related article is a stub. You can help Wikipedia by expanding it.

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 {{For|the Australian punk rock band|Frenzal Rhomb}}
-A '''Fresnel rhomb''' is a [[prism (optics)|prism]]-like device designed in [[1817]] by [[Augustin-Jean Fresnel]] for producing circularly [[polarized]] [[light]], in a manner similar to a [[wave plate]].
+A '''Fresnel rhomb''' is a [[prism (optics)|prism]]-like device designed in [[1817]] by [[Augustin-Jean Fresnel]] for producing circularly [[polarized]] [[light]]. However, in contrast to a [[wave plate]], the rhomb does not utilise birefringent properties of the material.
-The [[rhomb]] (actually, usually a right-[[parallelepiped]]) is shaped such that light entering one of the small faces is [[total internal reflection|internally reflected]] once from each of the two sloped faces, then exits through the other small face. The angle of internal reflection is the same in each case, and each reflection produces a 45° (π/4 [[radian]]s) [[phase (waves)|phase]] delay between the two linearly polarized components of the light. The net phase shift of 90° (π/2 radians) means that a linearly polarized beam entering the rhomb becomes [[circular polarization|circularly polarized]] on exit.
+The [[rhomb]] (usually a right-[[parallelepiped]]) is shaped such that light entering one of the small faces is [[total internal reflection|internally reflected]] twice: once from each of the two sloped faces before exiting through the other small face. The angle of internal reflection is the same in each case, and each reflection produces a 45° (π/4 [[radian]]s) [[phase (waves)|phase]] delay between the two linearly polarized components of the light. Hence on the first reflection, a linearly polarized beam will be elliptically polarized, and will emerge as circularly polarized on the second reflection.
-For visible light and a [[glass]] rhomb ([[refractive index]] ''n'' ≈ 1.5), an internal reflection angle of incidence of 48° or 54° is required.
+For visible light and a [[glass]] rhomb ([[refractive index]] ''n'' ≈ 1.5), an internal reflection angle of incidence of 48° or 54.6° is required.
 ==See also==
 *[[Fresnel equations]]
-== External link and reference ==
+== External link and references ==
+*Hecht, E. (1987). ''Optics: Second Edition''. Massachusetts: Addison-Wesley Publishing Company, Inc. ISBN 0-201-11611-1
-http://physics.kenyon.edu/EarlyApparatus/Polarized_Light/Fresnels_Rhomb/Fresnels_Rhomb.html
+*http://physics.kenyon.edu/EarlyApparatus/Polarized_Light/Fresnels_Rhomb/Fresnels_Rhomb.html
 {{optics-stub}}