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Videology Industrial-Grade Cameras - Mini Color Camera 2024 HP

202 terms

Photonics Dictionary: B

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Bragg spectrometer -> ionization spectrometer

Also known as the Bragg spectrometer. A system used for the x-ray analysis of crystal structure. In the instrument, a homogeneous beam of x-rays is directed on the known face of a crystal and the...

Babinet absorption rule

The rule stating that positive uniaxial crystals have greater absorption with respect to the extraordinary component of light, whereas negative crystals have greater absorption for the ordinary...

backlight compensation

The ability of a camera to compensate in cases where a subject with a large amount of background light would otherwise be obscured by blooming or silhouetting.

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...

band-elimination filter

A filter that suppresses a given range of frequencies, transmitting only those above and below that band. Also called bandstop filter.

bandwidth-limited operation

In fiber optics, the limitation on performance imposed by the system bandwidth rather than the amplitude of the signal.

barrel distortion

The negative distortion that causes a square grid pattern to be imaged as barrel-shaped.

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...

beam deflection tube

An electron-beam tube in which the current to an output electrode is regulated by the transverse motion of the tube's electron beam.

beam position

In computer graphics, the point on the display screen where the electron beam is located before the display instruction is executed. On directed beam display points, vectors and other graphic...

beam positioner

A device (e.g., prisms, lenses, tubes) used to align a beam in a system.

Bessel functions

Two formulas used in diffractometer analysis, the first giving the individual diffraction patterns of each aperture, the second representing the constant of the degree of an incoherent circular...

beta radiation

The high-speed electrons and positrons emitted by radioactive materials.

bidirectional reflectance distribution function

Unified notation for specification of reflectance in terms of both incident- and reflected-beam geometry; i.e., the ratio of reflected radiance in direction toward the viewer to the irradiance in...

bilinear interpolation

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....

binocular collimation

The adjustment of a binocular instrument so that the lines of sight of both telescopes are parallel.

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.

bionics

The application of observed operational processes of sophisticated living organisms to mechanical and electrical systems in order to analogize capabilities or efficiency.

biostimulation

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...

Bohr's frequency relation

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...

boundary extraction

In optical character recognition, an intermediate step between character location and feature extraction.

bright-field illumination

The illumination generally used in microscopy, whereby the specimen appears dark against a light background.

brightness resolution

The degree to which a pixel in a digital image represents the analog brightness of the corresponding point in the original image. It is dependent largely on the number of bits devoted to representing...

broadband incident radiation -> white light

Light perceived as achromatic, that is, without hue.

broadside radiation

Radiation that occurs perpendicular to the plane of the radiation device.

Brownian motion

The behavior of microscopic solid particles suspended in a fluid, first observed by botanist Robert Brown in 1827 as a continuous random motion.

bandstop filter -> band-elimination filter

A filter that suppresses a given range of frequencies, transmitting only those above and below that band. Also called bandstop filter.

bend -> deformation constant

Any of the constants that relate the tendency of the director to remain parallel to restoring torques throughout the media. The three constants of importance in liquid crystal displays are: splay --...

Bouguer's law -> Lambert's absorption law

Transmittance of a solution, or internal transmittance of a transparent solid, is an exponential function of the thickness of the layer.

B-scope

A cathode-ray display where information is represented visually as spots. Each spot's location is represented by a horizontal coordinate showing its bearing angle, and a vertical coordinate showing...

Babinet compensator

A device containing two opposed quartz wedges of equal angle, one wedge being movable along its length by a micrometer screw. The wedges are cut so that their fast directions are along, and...

Babinet principle

The principle stating that two diffraction screens, one being exactly the negative of the other, will form the same diffraction patterns.

Babinet-Jamin compensator

A Babinet compensator that contains the controlled motion of one prism with respect to the other. This idea was introduced by Jamin.

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.

back focal length

The distance from the final optic within a system to the rear image point of the system. See focal length.

backlash

In a mechanical system, any lost motion between driving and driven elements due to clearance between parts.

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.

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...

backscattering coefficient, b

Fraction of light counter propagating collinear with the incident source. Processes considering backscattering are Raman, Brillouin, Rayleigh and Mie.

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.

backward-wave oscillator

An amplifying device with a wide tuning range in which an electron gun sends a beam of electrons into a slow-wave structure. The electron beam and the electromagnetic wave move in opposite directions...

bacteriorhodopsin

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...

bakeout

The elimination of gases from the surfaces of a vacuum system by heating the surfaces when the pumping phase is occurring.

ballistic camera

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

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...

bandpass filter

A filter with a transmission that is high for a particular band of frequencies, but that falls to low values above and below this band.

bandwidth

The range of frequencies over which a particular instrument is designed to function within specified limits. See also fiber bandwidth.

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.

Photonics DictionaryB