Photonics Marketplace

Suppliers Products

Handbook Institutions Dictionary

Show Filters

Hide Filters

Type

DefinitionsAbbreviations/Acronyms

Browse by Letter

Excelitas PCO GmbH - PCO.Edge 11-24 BIO MR

PI Physik Instrumente - Microscope Stages HP ROS 11/24

8,726 terms

Photonics Dictionary

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...

biprism interference

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

BIRDIE

battery integration and radar display equipment

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...

birefringent crystal -> doubly refracting crystal

A transparent crystalline substance that is anisotropic relative to the velocity of light.

birefringent filter

A filter that transmits light in a series of sharp, widely spaced wavelength bands by its sandwich construction of alternating layers of polarizing films and plates cut from birefringent crystal.

BISDN

broadband integrated services digital network

bismuth silicon oxide

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

bispheric condenser -> dark-field condenser

A condenser that forms a hollow cone-shaped beam of light with its focal point in the plane of the specimen. If it is used with an objective having a numerical aperture lower than the minimum...

bistability -> optical bistability

The phenomenon that can render an optical resonator the equivalent of a semiconductor flip-flop. A bistable device will remain stable in two optical states, one of high transmission and another of...

bistable display

A matrix-controlled display that has information storage at the display surface, and requires that an element be addressed only once to assure that it is on or off.

bistatic reflectivity

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

bit

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.

bit

binary digit

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.

bit error rate

The ratio of the number of bits received incorrectly to the total number of bits transmitted digitally in a system.

bit mapping

In computer graphics, the assignment of each pixel on a display screen to its own switch in the computer memory.

BITE

built-in test equipment

bitoric lens

A lens, both surfaces of which are ground and polished into a toric or cylindrical form.

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,...

borosilicate crown glass

black hole

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...

black level

The level of the television picture signal that corresponds to the maximum limit of black peaks.

black light

Radiation from the invisible (usually ultraviolet) region of the spectrum.

black surface enclosure

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

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.

blackbody simulator

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...

blackbody source

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...

blacking -> optical blacking

A light absorbing material applied to ground optical surfaces during the process of making that surface non reflective. Such material should have a refractive index as high as that of the underlying...

BLADE

basic-level automation of data through electronics

blank

A piece of glass, quartz or other transparent material formed roughly by molding or cutting into the approximate shape and size of the finished part.

blanking

The process by which the raster beam in a video tube is cut off during the retracing and sync periods.

blaze

1. A plane that forms one side of the groove ruled on a diffraction grating. 2. To form the individual grooves of a grating with flat smooth faces, inclined to the surface by an angle known as the...

blaze height

Blaze height typically refers to a parameter in the context of diffraction gratings, which are optical devices consisting of a series of closely spaced parallel grooves or slits. The blaze height is...

blaze wavelength

The light wavelength for which the direction of reflectance from the groove face is identical to the angle of diffraction for a specified angle of incidence.

BLC

backlight compensation

bleach (or bleacher)

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

bleaching -> saturable absorber

A saturable absorber is a type of optical device that exhibits variable absorption properties depending on the intensity of incident light. In essence, it becomes less absorbent as the light...

blind approach beacon system

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...

blind spot

The spot on the retina where the optic nerve is attached; it is incapable of sensing light because of the absence of light receptors.

blindness

The inability to perceive visual images (visible radiant energy). In human beings, blindness is defined as a visual acuity of less than one-tenth normal vision.

blink comparator

An optical system that rapidly alternates two similar pictures or scenes to permit the detection of small dissimilarities between them.

blinking

Intentionally alternating the intensity of a display element in a graphic display device.

BLIP

background-limited infrared photoconductor

blister

An extended bubble or seed on glass, elliptically shaped and more than one-quarter inch (6.3 mm) in length.

blob

A group of adjacent pixels in an image representing the same value, as all black in a binary image.

block

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.

block reek

A type of scratch.

Photonics Dictionary

Need Help?