extraordinary ray

American  

noun

Optics, Crystallography.

1. the part of a doubly refracted ray that has changed speed and vibrations in the principal plane of the crystal.

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extraordinary ray British  

noun

1. optics the plane-polarized ray of light that does not obey the laws of refraction in a doubly refracting crystal Compare double refraction ordinary ray

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Etymology

Origin of extraordinary ray

First recorded in 1870–75

Example Sentences

One behaves normally and is called the ordinary ray, whereas the other does not obey Snell’s law and is called the extraordinary ray.

From Textbooks • Aug. 12, 2015

The ordinary ray behaves as expected, but the extraordinary ray does not obey Snell’s law.

From Textbooks • Aug. 12, 2015

Now the refractive index of Iceland spar is, for the extraordinary ray less, and for the ordinary greater, than for Canada balsam.

From Six Lectures on Light Delivered In The United States In 1872-1873 by Tyndall, John

Or is he more liable to error in noting the fact of his mental joy or sorrow, than in observing the effect of the extraordinary ray in double refraction?

From Fables of Infidelity and Facts of Faith Being an Examination of the Evidences of Infidelity by Patterson, Robert

Each of the others will be divided into an ordinary and an extraordinary ray, the one moving more slowly through the crystal than the other; the one, therefore, retarded with reference to the other.

From Six Lectures on Light Delivered In The United States In 1872-1873 by Tyndall, John