Glossary: K

A type of eyepiece design consisting of a plano-convex field lens and a cemented doublet lens as the eye lens.

Electro-optical device constructed from a crystal with attached electrodes used to modulate a laser beam. A phase delay of a laser transmitting through the crystal is modulated by applying a variable electric voltage, causing birefringence. The change is proportional to the square of the field, which is known as the Kerr effect.

See also Pockels Cell, Q-Switching

A type of optical mount capable of six degrees of freedom that are singularly constrained during alignment. It is designed to minimize stress to the optics or optical assemblies it holds. 

A measure of material hardness. A higher Knoop hardness corresponds to a stronger material.