Photonics Dictionary

A frame taken with a CCD camera over an exposure length of zero seconds with the lens cap on or the shutter closed and no light reaching the sensor. This frame shows the electronic noise in the...

Mathematical compensation for the nonhydrogenic behavior of recombination radiation levels of gases, based on the quantum effect method.

It is often necessary to estimate the value of what a pixel would be between neighboring pixels. This is accomplished by interpolating (or inserting) the value of a pixel between neighboring pixels....

An experimental lens used to produce interference fringes. A positive lens is cut into halves along its center, and the halves are separated. This produces a double image of a slit source set...

A type of piezoelectric translator that uses two thin strips of piezoelectric material, one expanding while the other contracts, to produce movement.

Bin picking, also known as bin picking automation or bin picking robotics, refers to the automated process of selecting and retrieving individual objects or components from a bin, container, or bulk...

Signal used in optical transmission systems to generate currents in a detector that are decoded with reference to a specified threshold.

Optical elements, often created by micromachining, lithography or vacuum deposition, that rely on diffraction of the collected energy as opposed to the more common refracting or reflecting optics....

An imaging technique that labels all gray pixels as either black or white before processing begins.

A microscope designed with two eyepieces (oculars), permitting the use of both eyes when viewing through the instrument.

The absolute luminance threshold for detection by the two eyes.

Binoculars are optical instruments used for magnifying distant objects by using two parallel telescopes mounted side by side. They allow users to see distant objects more clearly and in greater...

A term pertaining to devices (generally optical) designed for use with both eyes viewing through a single exit pupil. The term may be distinguished from binocular in that biocular instruments contain...

Bioluminescence is the natural phenomenon where living organisms produce light through a chemical reaction. In the context of photonics, bioluminescence has significant implications for both research...

A biomarker, short for biological marker, refers to a measurable and quantifiable indicator of a biological condition, process, or response. Biomarkers can be substances or characteristics that are...

Biometrics refers to the automated recognition of individuals based on their physiological or behavioral characteristics. These unique attributes are used to verify or identify individuals, often in...

Biomimicry, or biomimetic design, is the practice of emulating natural processes, systems, and structures found in biological organisms to solve human problems or create innovative technologies. It...

The technology that deals with the interaction of organic materials with light and other forms of radiant energy whose quantum unit is the photon. This includes the emission, detection, absorption,...

The action of a biological system responding to a single or multiple coherent particles of light produced from a laser source. Examples of laser biostimulation include: retinal interaction of light...

Also called proximity focus image intensifier. A compact image intensifier that utilizes a microchannel plate intensification stage. This is an in-line device that does not invert the image.

Electron lens consisting of an homogeneous axial electric field.

Birefringence is an optical property of certain materials that causes them to exhibit different refractive indices for light of different polarizations. In other words, when light passes through a...

A photorefractive material used in image processing, holography and optical switching.

A cosmic phenomenon in which the mass and density of a star pass a critical point so that the escape velocity matches the speed of light. For this reason, light and matter are "captured'' by the...

An enclosure whose walls are coated to absorb completely all radiation striking them.

A source that attempts to create the characteristics of an ideal blackbody. It consists of a cavity, generally spherical, made of an opaque material and insulated from thermal effects, with a small...

A blackbody source, often simply referred to as a blackbody, is a theoretical or practical physical object that absorbs all electromagnetic radiation incident upon it and emits radiation in a...

A chemical used in the developing of positive photographs that incites oxidation and thereby dissolves the negative silver to vary tone, color and intensity.

A ground-based navigation beacon that emits pulsed signals which are picked up by aircraft making an instrument (blind) approach in landing. The signal is transmitted to the aircraft's L-scan...

A supporting member used to hold optical parts during grinding and polishing. It also describes the assemblage of optical parts on the supporting member; e.g., a block of lenses or block of prisms.

An adhesive used to hold optical elements to blocking tools. It is usually a thermoplastic substance such as resin, beeswax, pitch or shellac.

Pitch, wax, resin or other cement suitable for holding optical parts to a spindle during grinding and polishing processes.

The loss of focus of a camera sensor because of excessive brightness, characterized by the enlargement of spot size and halation on a cathode-ray tube.

A blue diode laser is a type of semiconductor laser that emits light in the blue wavelength range of the electromagnetic spectrum, typically between 400 and 500 nanometers. Diode lasers are compact,...

A blur circle refers to the out-of-focus region in an image captured by an optical system. When an object in a scene is not in perfect focus, its image is spread out into a circular shape on the...

In the optical field, a piece of glass to which a lens or prism is cemented. The unit is ground and polished as a whole to obtain a sharp edge on the finished piece.

The law given by the formula: that is, the frequency of radiation emitted or absorbed by a system when E2 and E1 are the energies of the states among which transition takes place, and h is...

A bolometer that serves to record. The photographic record formed by the bolometer may be called bolograph or bologram.

A thermometric instrument used for the detection and measurement of radiant energy. Its essential component is a short narrow strip covered with a dead black absorbing coating and mounted at the...

The central hole running the full length of a laser capillary tube, in which electrical discharge and laser action take place. Also a similar hole in a hollow waveguide or a microchannel plate.

A Bose-Einstein condensate (BEC) is a state of matter that forms at temperatures close to absolute zero. It is named after Satyendra Nath Bose and Albert Einstein, who independently predicted the...

A boson is a type of fundamental particle that follows Bose-Einstein statistics, which dictate the statistical distribution of identical particles with integer spin. Bosons are one of the two main...

A spectrophotometer having a pair of identical collimators with two Glan polarizing prisms, one fixed in azimuth and the other rotatable, set in one collimator. A Brace prism serves as the dispersive...

In photography, the technique of taking multiple pictures of the same subject at different exposures to compensate for exposure miscalculations. Automatic bracketing is a feature on some cameras.