optic axis

noun

, Crystallography.

1. (in a crystal exhibiting double refraction) the direction or directions, uniaxial or biaxial, respectively, along which this phenomenon does not occur.

optic axis

noun

1. the direction in a uniaxial crystal or one of the two directions in a biaxial crystal along which a ray of unpolarized light may pass without undergoing double refraction

Word History and Origins

Origin of optic axis¹

First recorded in 1655–65

Example Sentences

The meteor was obviously going from the observer, its path making an angle with the optic axis of about 60.

From Project Gutenberg

A surface expressing the optical relations of such crystals is thus an ellipsoid of revolution about the optic axis.

From Project Gutenberg

This direction of no double refraction is called the optic axis of the crystal.

From Project Gutenberg