(in a crystal exhibiting double refraction) the direction or directions, uniaxial or biaxial, respectively, along which this phenomenon does not occur.
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
optic axis n.
The line connecting the anterior and the posterior poles of the eye.
- Optic canal
optic canal n. The short canal through the lesser wing of the sphenoid bone at the apex of the eye socket through which the optic nerve and the ophthalmic artery pass. Also called optic foramen.
- Optic capsule
optic capsule n. The embryonic structure from which the sclera of the eye develops.
noun 1. Printing. . noun, Printing. 1. a point about ten percent above the exact center of a printed page or layout. optic center n. The point in the lens of the eye where light rays cross as they move from the cornea to the retina.
- Optic cup
optic cup n. A two-walled cuplike depression, formed by invagination of the optic vesicle, that develops into the pigmented and sensory layers of the retina. Also called eyecup.