Photonics Dictionary

An instrument designed to give a visual indication to the pilot when the plane has strayed from a specific flight path.

3D profiling, also known as three-dimensional profiling, refers to the process of capturing, analyzing, and visualizing the three-dimensional shape, geometry, and surface characteristics of objects...

An Abbe condenser is a type of optical component used in microscopy to enhance the illumination of the specimen. Named after the German physicist Ernst Abbe, who developed it in the 19th century, the...

An Abbe-Porro prism, often referred to simply as a Porro prism, is an optical prism used in binoculars and other optical instruments to invert and reverse an image. It is named after the Italian...

An abridged spectrophotometer refers to a simplified or compact version of a traditional spectrophotometer, which is a scientific instrument used to measure the intensity of light at different...

An absorbing wedge is an optical device used to control the intensity of light passing through it by absorbing a portion of the light. It is typically used in experiments and optical systems where...

An absorption lens is a type of optical lens that not only focuses or diverges light but also significantly absorbs certain wavelengths of the incident light. This dual function makes it different...

Absorption spectroscopy is a fundamental analytical technique used to study the interaction between electromagnetic radiation and matter. It involves measuring the absorption of light by a sample...

Acousto-optic deflection refers to a phenomenon where the trajectory of light is altered by acoustic waves propagating through a material. This effect is utilized in acousto-optic devices, which are...

Acousto-optics is a branch of physics that deals with the interaction of sound waves (acoustic waves) and light waves (optical waves) within a medium. It primarily focuses on phenomena where acoustic...

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...

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...

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...

Back-side illumination (BSI) is a technology used in imaging sensors, particularly in digital cameras, where the light is allowed to enter the sensor from the back side, opposite to where the...

A device, either visual or electronic, that emits signals to identify set positions for use in the navigation of aircraft and ships along flight paths and channels, or as a warning against entering a...

A device that measures the spatial distribution of energy perpendicular to the propagation path of a radiant beam. An energy or power meter is typically used to monitor the amount of light passing...

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....

1. That action occurring when light passes through an optical interface at other than normal incidence, i.e., refraction. 2. The curving of a path of light that passes close by a massive object, due...

Catoptrics is the field of optics concerned with the reflection of light from reflective surfaces such as mirrors. It encompasses the study and analysis of how light rays interact with these...

Centration is the precise alignment of the optical center of a lens or optical element with its mechanical center or the axis of the mounting assembly. It is crucial for ensuring that the optical...

Circular dichroism (CD) is a spectroscopic technique used to study the structural characteristics of chiral (asymmetric) molecules, particularly biomolecules like proteins, nucleic acids, and certain...

Circular-ranging optical coherence tomography (CR-OCT) is a specialized imaging technique used in medical diagnostics and research to obtain high-resolution cross-sectional images of biological...

A coherent fiber bundle (CFB), also known as a coherent fiber optic bundle, is an assembly of multiple optical fibers arranged in a specific geometric pattern to maintain the spatial coherence of...

A colloid is a mixture in which one substance of microscopically dispersed insoluble particles is suspended throughout another substance. The particles in a colloid are larger than those in a...

A corner cube, also known as a corner reflector or retroreflector prism, is a type of optical device used to reflect light or electromagnetic waves back towards their source with minimal deviation in...

A prism formed by dividing a Nicol prism in a plane parallel to the path of vibration of the transmitted light and taking out the wedge-shaped piece. After the pieces are rejoined, the planes of...

A dichroic mirror, also known as a dichroic beamsplitter or interference filter beamsplitter, is an optical device that selectively reflects or transmits light based on its wavelength. Dichroic...

Differential interference contrast (DIC) microscopy, also known as Nomarski interference contrast microscopy, is an optical imaging technique used in microscopy to enhance the contrast of transparent...

Differential mode delay (DMD) is a parameter used to characterize the propagation characteristics of optical fibers, particularly in multimode fiber optic systems. It refers to the difference in...

The interference pattern formed by light waves diffracted at the edges of an object as seen on a screen placed in their path.

An optical diffuser is an optical component or material designed to scatter or diffuse light that passes through it. It is used to create a more even or uniform illumination, reduce glare, or soften...

When a block of glass (prism, window, filter, etc.) is placed into a converging light bundle, it increases the physical distance to the point of focus. The equivalent air path for that block of glass...

The Faraday effect, named after the English scientist Michael Faraday, is a phenomenon in physics where the polarization plane of light is rotated when the light passes through a transparent medium...

The principle that a light ray extending from one point to another will, after any number of reflections and refractions, follow the path requiring the least transit time. This is also known as the...

Fiber joints, also known as fiber optic splices, refer to the connection points where two optical fibers are permanently joined together to form a continuous optical transmission path. These joints...

A fiber optic gyroscope (FOG) is a type of gyroscope that uses the interference of light waves to detect changes in orientation or rotation. It operates based on the principle of the Sagnac effect,...

A fiber optic sensor is a device that uses optical fibers to detect and measure physical, chemical, biological, or environmental parameters. Unlike traditional electrical sensors, fiber optic sensors...

Fizeau fringes are interference fringes observed in an interferometer, specifically in a Fizeau interferometer. The Fizeau interferometer is named after the French physicist Armand Fizeau, who...

A rotating mirror coupled with a distant mirror and used in a system by Foucault to compute the velocity of light. Light moving from the rotating mirror to the distant mirror and back was following...

FTIR (Fourier transform infrared) spectrometer is a powerful analytical instrument used to obtain an infrared spectrum of absorption or emission of a solid, liquid, or gas sample. It operates based...

A field of physics that deals with light as if it truly were composed of rays diverging in various directions from the source and abruptly bent by refraction or turned by reflection into paths...

The term gradient-index profile refers to a specific type of refractive index distribution within an optical material. In optics, the refractive index of a material describes how much the speed of...

Postulated by Einstein in his theory of relativity. They are waves traveling at the speed of light and exerting force on matter in their path. They are produced by changes in the distribution of...