ordinary ray

American  

noun

1. Optics, Crystallography. the part of a doubly refracted ray whose velocity within a crystal is the same in any direction.

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ordinary ray British  

noun

1. the plane-polarized ray of light that obeys the laws of refraction in a doubly-refracting crystal Compare double refraction extraordinary ray

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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

Thus, in tourmaline the ordinary ray, which vibrates perpendicular to the principal axis, is almost completely absorbed, whilst the extraordinary ray is allowed to pass through the crystal.

From Encyclopaedia Britannica, 11th Edition, Volume 7, Slice 7 "Crocoite" to "Cuba" by Various

Optically, calcite is uniaxial with negative bi-refringence, the index of refraction for the ordinary ray being greater than for the extraordinary ray; for sodium-light the former is 1.6585 and the latter 1.4862.

From Encyclopaedia Britannica, 11th Edition, Volume 4, Part 4 "Bulgaria" to "Calgary" by Various

If the magnetic field associated with an S-Region extends into the high solar corona through which the rays pass, then the sense of rotation corresponds to the ordinary ray of the magneto-ionic theory.

From Disturbing Sun by Richardson, Robert S. (Robert Shirley)