Rochon prism

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A Rochon Prism Rochon Prism.svg
A Rochon Prism

A Rochon prism is a type of polariser. It is made from two prisms of a birefringent material such as calcite, which are cemented together. [1]

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The Rochon prism was invented by and is named after Abbé Alexis Marie Rochon. It is in many ways similar to the Wollaston prism, but one ray (the ordinary ray) passes through the prism undeviated. The Sénarmont prism is similar but transmits the s-polarized ray undeviated. In both the Rochon and the Sénarmont prisms the undeviated ray is ordinary on both sides of the interface. Rochon prisms are commercially available, but for many applications other polarisers are preferred.

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Sénarmont prism Type of polarizer

The Sénarmont prism is a type of polariser. It is made from two prisms of a birefringent material such as calcite, usually cemented together. The Sénarmont prism is named after Henri Hureau de Sénarmont. It is similar to the Rochon and Wollaston prisms.

Alexis-Marie de Rochon French physicist

Alexis-Marie de Rochon, known as Abbé Rochon, was born in Brest, France on 21 February 1741, and died in Paris on 5 April 1817. He was a French astronomer, physicist and traveller. He worked on lens design and crystal optics, inventing the Rochon prism polariser.

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References

  1. Damask, JN (2005). Polarization Optics in Telecommunications. New York: Springer. ISBN   0-387-22493-9.