Photonics Dictionary

The scientific observation of celestial radiation that has reached the vicinity of Earth, and the interpretation of these observations to determine the characteristics of the extraterrestrial bodies...

The study and the interpretation of the infrared emittances of celestial bodies and phenomena.

The detection and analysis of naturally formed extraterrestrial electromagnetic radiation within the radio frequency range of the spectrum.

The study of the celestial bodies, relative to x-ray emission. Satellites launched to study x-ray sources have revealed many new classes of galactic and extragalactic sources, as well as the...

An absorption band is a range of wavelengths, frequencies, or energies in the electromagnetic spectrum within which a substance absorbs radiation. It appears as a dark band in a spectrum where the...

An absorption line is a dark line in a spectrum that occurs when a specific wavelength of light is absorbed by atoms or molecules in a medium (such as a gas or a solid) as light passes through it....

An absorption spectrum is a graphical representation of the absorption of light by a material as a function of wavelength, frequency, or energy. It displays the specific wavelengths of light that are...

Active optics refers to a technology used in telescopes and other optical instruments to improve the quality of images by dynamically adjusting the shape of optical components, such as mirrors, in...

Adaptive deconvolution is a computational method that aims to improve the resolution and fidelity of signals or images that have been degraded by known or unknown factors, such as blur, noise, or...

Adaptive optics (AO) is a technology used to improve the performance of optical systems by reducing the effects of atmospheric distortions. The Earth's atmosphere can cause light passing through it...

Optical addressability refers to the capability to control or manipulate individual elements that emit or modulate light (such as pixels in a display or light sources in an optical network) using...

The American Astronomical Society (AAS) is a prominent professional association of astronomers and other scientists dedicated to the study of astronomy and related fields. Founded in 1899, the AAS...

An ammonia maser is a device that amplifies microwave radiation using ammonia gas molecules in a process analogous to how lasers amplify visible light through stimulated emission of radiation. The...

Aplanatic points refer to specific points in an optical system where certain aberrations, such as spherical aberration or coma, are minimized or eliminated. In an optical system, aberrations are...

An apochromat, often referred to as an apochromatic lens or apochromatic objective, is a type of optical system designed to minimize chromatic aberration. Chromatic aberration occurs when different...

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...

In astronomy, the method of deliberately viewing objects with peripheral vision to take advantage of the eye's greater sensitivity to faint light a few degrees from the optical center.

1. In astronomy, the angle measured clockwise (eastward) in a horizontal plane, usually from north (true north, Y-north, grid north or magnetic north). 2. With relation to the plane-polarized light...

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 CCD camera, or charge-coupled device camera, is a type of digital camera that utilizes a CCD image sensor to capture and record images. CCD cameras are widely used in various applications,...

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 cryogenically cooled long-wave infrared (LWIR) camera is a specialized thermal imaging device designed to detect infrared radiation in the long-wave infrared spectrum, typically ranging from 8 to...

A CubeSat is a type of miniaturized satellite characterized by its standardized size and modular design. CubeSats are typically used for scientific research, technology demonstration, educational...

A diffraction grating is an optical component consisting of a surface with a periodic structure of equally spaced, parallel grooves or rulings. These rulings act as an array of closely spaced slits...

In astronomy, the relation that states that the intensity of a star's visible radiation is inversely proportional to the square of the distance from which it is viewed.

A technique used in astronomy that requires a radio telescope to be directed at a point in the sky west of the object under observation. The Earth's rotation causes the object to drift through the...

An EMCCD (electron-multiplying charge-coupled device) camera is a type of scientific camera specifically designed for low-light imaging applications that require high sensitivity and fast readout...

An emission spectrum is a graphical representation or a characteristic pattern of the wavelengths or frequencies of light emitted by a source, such as an atom, molecule, or celestial object. It shows...

A wide-field multiobject spectroscopy system used in astronomy, in which a bundle of low-loss optical fibers positioned on the target images is rearranged at its other end into a linear array along...

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 Fizeau interferometer is an interferometric device that uses the principle of interference to measure the surface flatness and quality of optical components. It consists of a light source,...

A high-sensitivity camera is a type of camera designed to perform well in low light conditions, capturing clear and detailed images with minimal noise. These cameras typically feature advanced sensor...

A holographic grating is a type of diffraction grating that is produced using holographic recording techniques. It consists of a periodic structure of alternating transparent and opaque regions,...

An infrared camera, also known as a thermal imaging camera or IR camera, is a device that captures and visualizes the infrared radiation emitted by objects, revealing temperature variations across...

Infrared (IR) refers to the region of the electromagnetic spectrum with wavelengths longer than those of visible light, but shorter than those of microwaves. The infrared spectrum spans wavelengths...

An intensified charge-coupled device (ICCD) camera is an advanced imaging device that combines the capabilities of both an image intensifier and a charge-coupled device (CCD) sensor to achieve...

An interferometer is a scientific instrument that utilizes the principle of interference to measure differences in the path length, wavelength, phase, or amplitude of coherent electromagnetic waves....

A lateral shearing interferometer is an optical device used in interferometry to measure phase differences between two beams of light. Interferometry is a technique that combines and analyzes...

Luminosity refers to the total amount of energy emitted by an astronomical object, typically measured per unit time. It quantifies the intrinsic brightness of the object and is often expressed in...

Magnetorheological finishing (MRF) is a precision optics polishing technique used for shaping and finishing optical surfaces to achieve extremely high levels of smoothness and accuracy. It is...

In astronomy, the relative brightness of a celestial body. Originally a scale from 1 to 6, where 1 represented the brightest and 6 the faintest visible night sky objects. This scale has been expanded...

A maser (microwave amplification by stimulated emission of radiation) is a device that produces coherent electromagnetic radiation in the microwave frequency range. It is the microwave analog of a...

A microchannel plate (MCP) is a specialized electron multiplier device used in various applications such as particle detection, imaging, spectroscopy, and night vision technology. It consists of a...

A mid-infrared camera is a type of imaging device designed to capture images in the mid-infrared (mid-IR) spectral range, typically spanning wavelengths from approximately 3 to 12 µm. This...