Photonics Glossary and List of Formula Symbols
Our glossary of photonics terms is based on the definitions in the Encyclopedia articles, which can be considered as authoritative.
The most convenient way to get here is to click on “Definition” in the box with green left margin, which appears below the heading of each encyclopedia article page.
Further below there is a list of common formula symbols.
Glossary of Photonics Terms
This page summarizes the definitions of photonics terms, as they appear below the headings of many of the Encyclopedia pages.
| A | B | C | D | E | F | G | H | I | J | K | L | M |
| N | O | P | Q | R | S | T | U | V | W | X | Y | Z |
A
- Abbe number
- a measure ofthe chromatic dispersion of a transparent material
- ABCD matrix
- a 2-by-2 matrix describing the effect of an optical element on a laser beam
- absorbance
- the logarithm with base 10 of the inverse transmittance
- absorptance
- the fraction of incoming radiant flux which is absorbed by an object
- absorption
- a process where light energy is converted to another form of energy
- absorption coefficient
- a logarithmic measure for the distributed absorption in a medium
- absorption length
- the length over which absorption reduces the optical intensity to 1/e of its initial value
- acceptance angle in fiber optics
- the maximum incidence angle of a light ray which can be used for injecting light into a fiber core or waveguide
- achromatic optics
- optical devices or setups with minimized chromatic aberrations
- acousto-optic deflectors
- acousto-optic devices for deflecting and scanning laser beams
- acousto-optic frequency shifters
- acousto-optic devices for shifting the optical frequency of a laser beam
- acousto-optic modulator drivers
- electronic drivers for operating acousto-optic modulators
- acousto-optic modulators
- optical modulators based on the acousto-optic effect
- acousto-optic Q-switches
- acousto-optic modulators used for Q-switching of lasers
- acousto-optic tunable filters
- acousto-optic devices which can be used for filtering light, controlled with an RF input
- actinometry
- a field of metrology which is based on counting radiation quanta instead of registering powers
- active fibers
- optical fibers containing laser-active dopants in the fiber core
- active mode locking
- a technique of mode locking, based on active modulation of the intracavity losses or the round-trip phase change
- adaptive optics
- a class of techniques where wavefront distortions are actively compensated
- additive-pulse mode locking
- a technique for mode locking a laser, using a nonlinear interaction in an external resonator
- adiabatic soliton compression
- a pulse compression technique based on the adaptation of solitons to slowly varying propagation parameters
- afocal optical systems
- optical systems which output parallel rays for parallel input rays
- alexandrite lasers
- solid-state lasers based on alexandrite (Cr3+:BeAl2O4) crystals
- alignment lasers
- lasers used for alignment purposes
- alignment sensitivity of optical resonators
- the sensitivity of a laser, an optical resonator or some other device with respect to misalignment
- all-solid-state lasers
- laser systems containing solid-state devices only, in particular no discharge lamps or gas or dye lasers
- amplification factor
- the factor by which the power of a signal is amplified
- amplified spontaneous emission
- a process where spontaneously emitted radiation (luminescence) is amplified
- amplifier chains
- amplifiers consisting of several stages
- amplifier noise
- noise introduced to a signal in an amplifier device
- amplitude-squeezed light
- light with an intensity noise below the shot noise level
- anamorphic prism pairs
- prisms pairs for reshaping laser beams
- anti-reflection coatings
- optical thin-film coatings for reducing reflections from surfaces
- aperture stops
- apertures which limit the angular range of received input light of imaging systems
- apochromatic optics
- optical elements or systems designed to minimize chromatic aberrations to a greater extent than standard achromatic optics
- arc lamps
- gas discharge lamps based on an electrical arc, or continuously operating gas discharge lamps
- argon-ion lasers
- gas lasers based on light amplification in ionized argon in a gas discharge
- arrayed waveguide gratings
- optical filter or multiplexer devices based on arrays of waveguides
- aspheric optics
- optical elements with non-spherical surfaces
- astigmatism
- a kind of optical aberrations; alternatively, a defect of optical lenses or a property of laser beams
- astrophotonics
- the application of advanced photonics for astronomical instrumentation
- autocollimators
- optical instruments for precisely measuring angular alignments
- autocorrelators
- devices for measuring the intensity or field autocorrelation function of light, mostly used for determining the duration of ultrashort pulses
- avalanche photodiodes
- photodiodes with internal signal amplification through an avalanche process
- axicons
- lenses with a conical surface
B
- B integral
- a measure of the nonlinear phase shift of light, e.g. in an amplifier
- Babinet–Soleil compensators
- adjustable waveplates (retarder plates) containing three birefringent plates