Definitions

Functional near-infrared spectroscopy (fNIRS) is a non-invasive neuroimaging technique that measures changes in hemoglobin concentration in the brain. It utilizes near-infrared light to penetrate the...

A monitoring technique used to measure the oxygen saturation levels in the brains of patients, commonly in operating room and neonatal intensive care unit settings. The technique, which is based on...

The shortest wavelengths of the infrared region, nominally 0.75 to 3 µm.

An alexandrite laser is a solid-state laser that utilizes a synthetic crystal made from the rare earth element alexandrite (BeAl2O4:Cr3+). This crystal is capable of emitting laser light in the...

An arc flash is a sudden release of electrical energy due to an electric arc — a continuous, high-current discharge of electricity between conductors or from a conductor to ground. Arc flashes...

Chalcogenide refers to a class of compounds containing elements from group 16 of the periodic table, which includes sulfur (S), selenium (Se), and tellurium (Te). These elements are known as...

A detector array refers to a collection of individual detector elements arranged in a two-dimensional grid or matrix format. Each element within the array is capable of detecting electromagnetic...

A femtosecond laser is a type of laser that emits ultrashort pulses of light with durations on the order of femtoseconds, where one femtosecond is equal to 10-15 seconds. These lasers are capable of...

A filter, partially opaque to near-ultraviolet, visible and infrared radiation, that may be made by exposing and processing photographic film. Such materials are almost equally opaque to radiation of...

A free-electron laser (FEL) is a type of laser that generates coherent, high-intensity electromagnetic radiation by using a beam of accelerated electrons as the lasing medium. Unlike traditional...

A frequency comb is a precise and regular series of equally spaced spectral lines, or frequencies, that are generated with great accuracy. The term "frequency comb" is often associated with the Nobel...

A GaAlAs laser is a type of semiconductor laser diode that emits light in the near-infrared region of the electromagnetic spectrum. It is composed of layers of gallium, aluminum, and arsenic, hence...

Gallium arsenide phosphide (GaAsP) is a semiconductor alloy composed of gallium (Ga), arsenic (As), and phosphorus (P). It is commonly used in the fabrication of optoelectronic devices, particularly...

One of the first lasers to find practical application. Generally, the pumping mechanism is an electric discharge, although some high-power forms employ chemical reaction or gas compression and...

A type of glass used in near-infrared optical components, in which germanium is used as a cation instead of silicon.

A hyperspectral imaging camera is a sophisticated imaging device capable of capturing and processing data across a wide range of wavelengths within the electromagnetic spectrum, typically from...

An InGaAs (indium gallium arsenide) camera is a type of imaging device that utilizes InGaAs sensors to capture images in the near-infrared (NIR) spectrum. InGaAs is a semiconductor material that is...

Indium phosphide (InP) is a compound semiconductor material composed of indium (In) and phosphorus (P). It belongs to the III-V group of semiconductors, where elements from groups III and V of the...

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...

An infrared lens is an optical component specifically designed and optimized for transmitting, focusing, or manipulating infrared (IR) radiation within the infrared spectrum. These lenses are used in...

An infrared light-emitting diode (IR LED) is a semiconductor device that emits infrared light when an electric current passes through it. Similar to standard LEDs that emit visible light, IR LEDs are...

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 InGaAs photodiode refers to a photodetector device that is constructed using a semiconductor material composed of a combination of indium (In), gallium (Ga), and arsenic (As). The term InGaAs...

A semiconductor diode operating in either a coherent or incoherent mode that is used as a near-infrared or visible source in triggering light-activated devices.

A laser crystal, also known as an active medium or gain medium, is a solid-state material used in the construction of lasers. The primary function of the laser crystal is to amplify light by...

A long-pass filter is an optical filter that allows longer wavelengths of light to pass through while blocking or attenuating shorter wavelengths. These filters are designed to transmit light with a...

Long-wave infrared (LWIR) refers to a specific range of the infrared spectrum. Infrared radiation is divided into three main categories based on wavelength: near-infrared (NIR), mid-wave infrared...

A lamp that has mercury in a tube or bulb that has first been evacuated. The electricity travels through the vapor between the electrodes and produces a blue-green light that is rich in ultraviolet...

Metabolic imaging refers to the visualization and quantification of metabolic processes within living organisms, tissues, or cells using various imaging techniques. It provides insights into the...

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...

MWIR stands for mid-wave infrared, referring to a specific range of wavelengths within the infrared spectrum. Infrared radiation is categorized into three main regions based on wavelength:...

A multiline laser system refers to a type of laser that is capable of emitting multiple discrete wavelengths or spectral lines simultaneously. Unlike single-line lasers, which produce radiation at a...

Multispectral imaging is a technique that involves capturing and analyzing images at multiple discrete spectral bands within the electromagnetic spectrum. Unlike hyperspectral imaging, which acquires...

A near-infrared (NIR) camera is an imaging device designed to capture images in the near-infrared region of the electromagnetic spectrum. The near-infrared spectrum typically extends from about 700...

A near-infrared (NIR) spectrometer is an analytical instrument used to measure the absorption, transmission, or reflection of light in the near-infrared region of the electromagnetic spectrum....

Near-infrared spectroscopy (NIRS) is a non-invasive analytical technique that uses the near-infrared region of the electromagnetic spectrum to study the absorption of light by molecules in a sample....

An optical clock is a highly precise and advanced timekeeping device that relies on the oscillations of electromagnetic radiation in the optical or ultraviolet part of the electromagnetic spectrum....

Optical coherence tomography (OCT) is an imaging technique used in medical diagnostics and biomedical research to obtain high-resolution, cross-sectional images of biological tissues. An OCT imaging...

Optical coherence tomography (OCT) is a non-invasive imaging technique used in medical and scientific fields to capture high-resolution, cross-sectional images of biological tissues. It provides...

A laser-pumped crystal with nonlinear optical properties inside of an optical resonator in which the output generates coherent light whose output can be tuned continuously over a variety of infrared...

Any organic substance, that when dissolved in appropriate liquid based solvents will absorb and emit electromagnetic radiation in the near ultraviolet, visible and near infrared spectral regions....

A laser having a lasing material that is a fluorescing organic dye. Depending on the dye used, it can produce emission in any part of the visible spectrum into the near-infrared and ultraviolet, and...

A light therapy that utilizes nonionizing light sources, including lasers, LEDs, and broadband light, in the visible and infrared spectrum. It is a nonthermal process involving endogenous...

Photoconductive antenna (PCA) is a semiconductor element that generates or detects high-frequency electromagnetic signals. Compact PCAs based on gallium arsenide (GaAs) or indium gallium arsenide...

Phototherapy is a medical treatment that involves the use of light to treat various conditions, particularly those related to the skin or mood disorders. There are different types of phototherapies,...

An optical fiber in which ions of a rare-earth element, such as neodymium, erbium or holmium, have been incorporated into the glass core matrix, yielding high absorption with low loss in the visible...

Reflectance spectroscopy is a technique used to analyze the reflective properties of materials across various wavelengths of the electromagnetic spectrum. By measuring the reflectance of light from a...