Photonics Dictionary: A

An astronomical mirror, also known as a telescope mirror or primary mirror, is a key component of a reflecting telescope. It serves as the primary optical element responsible for gathering and...

An astronomical telescope is a type of optical instrument designed to gather and magnify light from distant celestial objects for observation and analysis. It typically consists of two main optical...

A method of data multiplexing that can provide large, instantaneous bandwidths for busy traffic while permitting slow traffic to use that bandwidth between bursts. Very short, fixed-length packets or...

An atomic absorption spectrometer (AAS) is an analytical instrument used to determine the concentration of specific chemical elements in a sample by measuring the absorption of light at...

Spectrometric analysis of the distinct and characteristic spectra of atoms of elements. The atoms are energized to emit radiant energy, which, when dispersed by a prism or diffraction grating,...

An atomic force microscope (AFM) is a high-resolution imaging and measurement instrument used in nanotechnology, materials science, and biology. It is a type of scanning probe microscope that...

Attenuated total reflectance (ATR) spectroscopy is a technique used in analytical chemistry to obtain IR spectra of samples. It is particularly useful for analyzing solid and liquid samples without...

Attenuation refers to the gradual loss or reduction of intensity, force, or magnitude of a particular property as it propagates through a medium or travels over a distance. This concept is prevalent...

An attenuator is an electronic or optical device used to reduce the power or intensity of a signal without significantly affecting its waveform or other characteristics. Attenuators are commonly used...

Attosecond-pump attosecond-probe spectroscopy (APAP) is an advanced technique in ultrafast spectroscopy that allows scientists to study the dynamics of electronic processes occurring on extremely...

Augmented reality (AR) is a technology that integrates digital information, typically in the form of computer-generated graphics, images, or data, with the real-world environment in real-time. AR...

The indistinct, less luminous portion lying immediately outside an electric arc whose spectrum often differs from that of the core.

A device for automatic exposure control in which a motor-driven diaphragm adjusts the aperture in response to a signal from a photocell detecting ambient light.

Technique of projecting an illuminated target at infinity and receiving the target image after reflection from a flat mirror surface.

An autocollimator is an optical instrument used for measuring small angular deviations with high precision. It operates on the principle of autocollimation, where a light source is directed onto a...

Autofluorescence refers to the natural emission of fluorescence exhibited by certain biological structures or molecules when exposed to light. Unlike fluorescence that results from the application of...

A means of adjusting the sharpness of an image automatically, with a sensor for estimating distance or contrast and a drive mechanism to adjust the lens. Active systems generate a light source to...

Automated optical inspection (AOI) is a technology used in manufacturing processes, particularly in electronics, to automatically inspect and detect defects or anomalies in products. AOI systems use...

A system for automatic industrial process control or measurement, consisting of an optical module for image acquisition, a segmentation processor to isolate the image from its background, and an...

A microscope to which a beamsplitter and illuminated reticle have been added to measure the radius of curvature of a spherical surface by locating both surface and center and calculating the distance...

A receiver for optical communications systems consisting of a symmetric binary, pulse-code-modulated transmitter, a log-normal channel and an array of independent photocounting detectors that yield...

In gradient index optics, a gradient profile in which the refractive index varies along the direction of light propagation, or optical axis. Axial gradient lenses can be used to correct spherical...

A method of designing lasers whereby the laser rod is cut into elliptical discs and cooled by running water over the disc surfaces. The cooling circuit decreases the radial temperature gradients in...

A vapor-phase oxidation process for fabricating graded-index optical fibers. It differs from outside vapor phase deposition in that the preform is developed radially rather than longitudinally. An...

An axicon is a type of optical component characterized by its conical shape and its ability to transform a collimated Gaussian beam of light into a ring-shaped beam with a gradually increasing...

A straight line, real or imaginary, passing through a body and indicating its center; a line so positioned that various portions of an object are located symmetrically in relation to the line. See...

Azadioxatriangulenium is a type of organic compound with a unique triangular molecular structure. It is often abbreviated as ADOTA. This compound belongs to the class of polycyclic aromatic...

Azimuthal polarization refers to a specific polarization state of light where the electric field vector of the electromagnetic wave points along the azimuthal direction (around the propagation axis)....