Photonics Dictionary: B

Calculates the exponential growth of the least stable spatial frequency in a laser beam, and is the numerical equivalent of the nonlinear phase shift along the laser system's optical axis.

Backscatter refers to the phenomenon in which radiation or waves are scattered backward, opposite to the direction of the incident beam. This occurs when the incident radiation encounters a target or...

A light-harvesting protein found in the purple membrane of a micro-organism called Halobacterium halobium. The protein undergoes a photocycle that involves several binary photochemical reactions that...

A camera that uses multiple exposures to record the trajectory of an ordnance from a ground-level position.

The roughness profile shape from which light scattering is expected to occur.

Bardeen-Cooper-Schrieffer theory of superconductivity, based on the notion that electrons with opposite momentum and spin are paired as a result of forces arising from lattice vibrations. The theory...

A system of optical components designed to increase the diameter of a radiation beam. Usually an afocal system.

The intensification of a latent image, because of exposure to light to which the emulsion is otherwise insensitive.

Transmittance of a stable solution is an exponential function of the concentration of the absorbing solute.

In optics, a collapsible structure situated between the lens and film of a camera to allow variation of the distance between them while preventing surrounding light from exposing the film.

Mathematical definition for the changes that occur between potential and kinetic energy. These formulas express wave motion.

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...

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.

A contraction of binary digit; the fundamental unit of digital computing, a bit is either 1 or 0, expressing the binary state of on or off, true or false, etc.

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 constant equal to the universal gas constant divided by the Avogadro number. It is approximately equal to 1.38 x 10-23 J/K and is commonly expressed by the symbol k.

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...

The simplest, most inexpensive type of camera, which is shaped as an oblong or square box, containing the simplest lens, shutter and viewfinder, as well as the most elementary means of registering...

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.

The law expressing the condition under which a crystal will reflect a beam of x-rays with the greatest amount of distinction or resolution and, at the same time, denoting the angle at which the...

An experimental model of an electrical circuit or complex assembly; a prototype.

Brillouin scattering is a phenomenon in physics where an incident electromagnetic wave (usually light) interacts with acoustic phonons (quantized lattice vibrations) in a material, resulting in the...