Photonics Dictionary

In optics, degreasers or ultrasonic arrangements used for removing pitch, cement or polishing material from lenses during manufacture. It also may refer to manual cleaning devices used immediately...

An area in which airborne particulates can be monitored and controlled so that given size particles do not exceed a specified concentration, thereby eliminating potential dysfunctions in gyroscopes,...

Optical elements that have been coated with one or more layers of dielectric, or metallic material. These coatings serve to reduce or increase reflection from the surface, and to protect the surfaces...

A numerical representation of the rate at which a material will exhibit dimensional changes as a direct result of changes in temperature.

Deformation of a material caused by mechanical factors, especially constant pressure, and not attributable to thermal effects.

A test used to measure the degree of fading of different colored materials, especially those involving organic dyes, which tend to fade when exposed to bright sunlight, to a damp atmosphere or to...

A color center, in the context of materials science and condensed matter physics, refers to a specific type of crystallographic defect in a crystalline structure that introduces color to the...

The detection and analysis of the relative response of a material to light over the range of wavelengths.

A colorimeter is a device used to measure and quantify the color characteristics of an object or a light source. It provides objective and standardized color information, typically expressed in terms...

Computer numerically controlled (CNC) grinding is a manufacturing process that utilizes computerized controls and precision machining tools to remove material from a workpiece. In CNC grinding, a...

A technique used to store wavefront information on thin polarization information-recordable materials by controlling the polarization angle of a small illuminating spotlight in each sampling cell on...

A phase reflection scanner that eliminates the need for a complex translation device while maintaining a high-energy-density level during laser materials processing. These devices direct and focus...

A material property that is the inverse of its resistance to the flow of electricity.

A partially filled or empty energy band through which electrons can move easily. The material can therefore carry an electric current. The term is usually applied to semiconductors.

A type of laser welding of thin materials using a defocused or low-power carbon dioxide laser beam. The energy is absorbed by the material through conduction and melts the material to produce an edge...

Reciprocal of the dispersive power of an optical material. See Abbe constant.

Continuous wave (CW) refers to a type of signal or transmission where the signal is constant and does not vary with time. In various contexts, the term is used to describe continuous, uninterrupted...

A camera mounted on an optical bench with an easel to hold the material to be copied. Magnification can be varied over a wide range by sliding the camera and easel.

A threadlike inclusion within a blank of optical glass. Rarely found in quality optical materials.

A mass-relieving method whereby material is removed through the sides of a reflector in a direction parallel to the surface. A method of cutting a cylindrical piece of material from a large piece.

A corner cube, also known as a corner reflector or retroreflector prism, is a type of optical device used to reflect light or electromagnetic waves back towards their source with minimal deviation in...

A compound lens, the dimensions and materials of which have been so chosen that the lens is appreciably free of aberrations.

A coverslip, also known as a cover glass or cover slip, is a thin and flat piece of transparent material typically made of glass or plastic. It is used in microscopy to cover a specimen mounted on a...

The deformation of a material at high levels of stress, often associated with elevated temperatures.

A solid with a structure that exhibits a basically symmetrical and geometrical arrangement. A crystal may already possess this structure, or it may acquire it through mechanical means. More than 50...

A diode with a semiconducting material, such as germanium or silicon, for one electrode, and a fine wire "whisker'' which lies on the semiconductor, as the other electrode. The low capacitance...

Glass of special composition that is melted, formed into desired shapes, and subjected to a high-temperature treatment in which the glass undergoes a stage of nucleic formation, and a second stage,...

The temperature above which a ferromagnetic material becomes only paramagnetic.

Custom lapping and polishing services involve specialized processes used to improve the surface finish and dimensional accuracy of components to meet specific requirements or standards. These...

Adhering material used to glue optical components that transmit in the infrared. It is easily dissolved by acetone.

A cylindrical lens is an optical component that has different curvatures along its two orthogonal axes, resulting in a shape resembling a cylinder. Unlike spherical lenses, which have the same...

Popular process for silicon and polycrystalline production that consists of an alteration of the original state of a substance; thus, single-crystal materials can be used to form a polycrystal.

A lightproof box used for storing photosensitive materials.

A room that is light-tight, permitting total darkness or illumination with a safelight when working with photosensitive materials.

A concave surface that has too much negative power; i.e., its radius of curvature is too short. This condition can be corrected if material is removed from the center section of the polisher.

Deep ultraviolet (DUV or deep-UV) refers to a specific range of ultraviolet light with shorter wavelengths than those in the UV-A and UV-B regions. The exact wavelength range considered as DUV can...

Description of a material, such as a water-soluble salt, that will continue absorbing moisture from the surrounding atmosphere until it dissolves into a liquid.

1. An instrument used to measure the opacity or density of dyes, pigments or dispersed particles that form an image in or on a medium, such as a photographic film. 2. A device used to measure the...

The region at the PN junction in a semiconductor radiation detector where the potential energies of the two materials create an energy barrier, which results in an electrical field that depletes the...

The ray refracted by a sphere of transparent material that travels back as closely as possible to the original path formed by the incident ray.