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Videology Industrial-Grade Cameras - Mini Color Camera 2024 HP

70 terms

Photonics Dictionary: B

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Bardeen-Cooper-Schrieffer theory -> BCS theory

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...

beauty defect

A defect on or in an optical element that does not appreciably impair the function of the surface.

Becquerel effect

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

biprism interference

Light interference fringes that can be viewed on a screen near a biprism.

bit boundary block transfer

A data transfer function that moves a rectangular group of pixels between bit maps. Often used in displaying cursors and pop-up windows.

bowl-feed machine

A polishing machine in which the rouge slurry is contained in a bowl and is constantly diverted mechanically so that it flows over the work.

buffer

1. In fiber optics, a protective material applied as an optical fiber cover that has no optical function. 2. In image processing, a peripheral that stores data between two active processing stages.

baseband response function -> transfer function

The complex function, H(f), equal to the ratio of the output to input of the device as a function of frequency. The amplitude and phase responses are, respectively, the magnitude of H(f) and the...

BCS theory

back channel

A channel for communication with the source in an otherwise unidirectional network, such as a channel that provides interactive features in a cable television network.

backlighting

The forming of a clear silhouette of an object by placing a light source behind it. Used in machine vision when surface features of an object are not important.

backlit

Refers to a display or screen that is illuminated from behind; the light is transmitted as opposed to reflected.

backreflection -> narcissus

A defect in infrared systems that appears as a dark circular area on a displayed image, caused by radiation reflecting into a detector. It can be reduced by low-reflective coatings or by altering the...

backscatter

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...

backstreaming

The term used in reference to vacuum systems using oil and diffusion pumps, describes the migration of pump fluids and their decomposition products into the vacuum chamber.

baffle

An opaque shielding device designed to reduce the effect of stray light on an optical system.

balloon-borne astronomical system

Any instrument or system carried by a balloon to the upper atmosphere to measure and record atmospheric information, such as radiation observations, while reducing atmospheric interference.

band-to-band photoluminescence

The emission of a photon by the return of an excited carrier from the conduction band to the valence band of a semiconductor along a radiative recombination path. The resulting photoluminescence...

bandgap

In semiconductor physics, the term bandgap refers to the energy range in a material where no electronic states are allowed. It represents the energy difference between the valence band, which is the...

barcode scanner

An optical scanning device designed to read information printed in the form of bars of different size by detection and processing of the varying reflectivity of light in the barcode.

Barlow lens

A negative lens used to increase the effective focal length of a telescope objective.

bay

In optical character recognition, a feature at the boundary of a character.

beam divider -> beamsplitter

A beamsplitter is an optical device used to divide a beam of light into two or more separate beams, typically by reflecting a portion of the incident light while transmitting the remainder....

beam noise -> noise current

Any noise or current fluctuation that prevents precise measurement of the signal current. Both dark current and signal current have random fluctuations that affect the arrival of pulses. Thermal...

beam optics -> Gaussian beam optics

The area of optics that deals with the propagation of Gaussian laser beams in free space, or any general medium - i.e. lenses- under the paraxial (small divergence angle) approximations. Gaussian...

beam shaper

A beam shaper is an optical device or system designed to modify the spatial profile or intensity distribution of a laser or light beam. The goal is to transform the incoming beam into a desired shape...

beam table

Laser light show effects equipment including optics and mechanical devices that reflect, position or distort the laser beam, but not including the laser itself.

beamsplitter

A beamsplitter is an optical device used to divide a beam of light into two or more separate beams, typically by reflecting a portion of the incident light while transmitting the remainder....

beat

The signal formed when two signals, such as light waves, of different frequencies are present simultaneously in a nonlinear device. The frequency of the beat is equal to the difference in frequency...

Bertrand lens

A small convergent lens, located between the objective and eyepiece of a microscope, that focuses an image of the upper focal plane of the objective in the focal plane of the eyepiece. It is commonly...

beta site

A facility selected by mutual agreement of the user and the prospective vendor to test a prototype before it is offered for sale.

bevel

A chamfer ground on the edge of a lens or prism. Bevels are used to prevent chipping or to achieve a mechanical fit.

Biberman factor

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

biconic connector

A type of fiber optic connector consisting of two cone-shaped ferrules aligned by a mating sleeve.

bifocal lens

A two-part lens that has a different focal length for each part. Generally, it is used in eyeglasses to correct for both near and far vision.

Billet's split lens

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...

binary on-off

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

binocular

Designating any instrument in which both eyes can be used to view the image to achieve a stereoscopic effect, or merely to facilitate observation. See also prism binoculars.

binocular parallax

The difference in angular bearing of an object as seen by the two eyes, due to the separation of the visual optical axes.

binocular vision

The ability of the two eyes to see an object from two slightly different points of view. This difference allows an individual to perceive the depth and dimension of the object in view.

bioluminescence

Heatless light emissions from living organisms caused by the combination of oxygen and pigments such as luciferin.

biomarker

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

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...

bipolar

Refers to transistors in which the working current flows through two types of semiconductor material: N- and P-type. In bipolar transistors, the working current consists of both positive and negative...

biprism

A piece of glass polished flat on one side, with a pair of polished faces that form an angle close to 180° on the other side, the dividing edge running down the middle of the plate. It is used...

birefringence

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...

bistatic reflectivity

Characteristic of a reflector that reflects light along a different line or lines than that of the incident ray.

Bjerrum screen

In ophthalmic practice, an instrument that determines the boundaries of the field of view. It is composed of a 2-m square of black velvet with a white spot center at which the patient, 1 m away,...

blackbody

An ideal body that completely absorbs all radiant energy striking it and, therefore, appears perfectly black at all wavelengths. The radiation emitted by such a body when heated is referred to as...

blackbody locus

With respect to a chromaticity diagram, this is the locus of points that represent the chromaticities of blackbodies possessing different color temperatures.

Photonics DictionaryB