Photonics Dictionary: I

Also called calcite. A natural hexagonal crystal of calcium carbonate. It cleaves readily into rhomboids useful in the study of polarized light.

An instrument in which an object's image, produced by a lens of known focal length, is used to determine the object's distance from the instrument when its size is known, or the object's size if the...

A camera tube that employs a high-velocity electron beam to scan a photoemissive mosaic and to store electrical charge patterns.

A crystal that is devoid of any mosaic structure and that can reflect x-rays, relative to the Darwin-Ewald-Prins law.

Any filter in which the range of frequencies within a chosen radius suffers no attenuation and the range of frequencies outside the radius is entirely attenuated.

A theoretical instrument conceived of as a box that receives a beam of radiation of any arbitrary polarization angle and produces a new beam, coaxial with the incident beam, having a specified new...

A system that transmits and receives identification codes to facilitate the discrimination between enemy and friend in a tactical situation.

Pertaining to the possession of photoelectric characteristics as a result of the properties of the true crystal and not of foreign materials.

In semiconductor physics and materials science, the term "III-V materials" refers to compounds composed of elements from group III and group V of the periodic table. More specifically, these...

Luminous flux incident per unit area of a surface; luminous incidence. (The use of the term "illumination" for this quantity conflicts with its more general meaning.)

Source of radiation defined or specified by its spectral power distribution.

Metamerism that occurs when the light source is changed.

Characteristic of a surface or object that has luminous flux incident upon it.