Photonics Dictionary

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...

The absolute luminance threshold is the lowest luminance level of a light source or illuminated object that can be detected by the human eye under specific conditions. This threshold represents the...

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...

Adiabatic laser colorimetry is a technique used to measure the color of materials based on the principle of adiabatic demagnetization. Principle: Adiabatic laser colorimetry relies on the...

Beam profiling is a technique used to characterize and analyze the spatial intensity distribution of a laser beam. It involves measuring and visualizing how the optical power or intensity is...

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....

A technique in which a beam of x-rays is directed against a crystal, the atoms of which, because of their lattice arrangement, reflect the ray in the same way as a series of plane surfaces. If the...

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 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 lidar (light detection and ranging) technique used in pollution monitoring. Two light beams are emitted simultaneously, one at a wavelength that will be absorbed by the target particles, and the...

Diffuse reflectance spectroscopy (DRS) is a nondestructive analytical technique used to investigate the optical properties of materials, particularly in the field of spectroscopy. Unlike traditional...

A distributed feedback laser (DFB laser) is a type of semiconductor laser diode designed to emit coherent, narrow-bandwidth light with precise control over the wavelength. It achieves this through a...

A spectroscope having a divided circle and a means for the rapid reversal of prisms for the measurement of refractive index of the prism for a specific wavelength.

Emission spectroscopy is a technique used to study the emission of electromagnetic radiation (light) by atoms, molecules, or ions when they undergo transitions from excited states to lower energy...

In surface height measurement of optics with steep slopes, the use of two short visible wavelengths to synthesize a longer, equivalent wavelength.

An etalon is an optical device that consists of two parallel reflecting surfaces separated by a precise and known distance. It operates based on the principle of optical interference and is used to...

Etaloning is an optical phenomenon that occurs in imaging systems, particularly in devices such as spectrometers, interferometers, and cameras. It is characterized by the appearance of interference...

A fiber Bragg grating (FBG) is a type of optical filter that is inscribed or "written" into the core of an optical fiber. It consists of a periodic modulation of the refractive index along the length...

A fiber optic attenuator is a passive optical component designed to attenuate or decrease the intensity of an optical signal traveling through a fiber optic link. It achieves this by introducing a...

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...

A fiber optic spectrometer is a device used for measuring the spectral content of light. It utilizes optical fibers to transmit light from a source to a spectrometer unit, where the light is...

A fiber-coupled LED (light-emitting diode) refers to an LED device that is optically coupled to an optical fiber for the purpose of efficient light transmission. In this configuration, the LED serves...

Flow cytometry is a powerful technique used in biology and medicine for the quantitative analysis of the physical and chemical characteristics of cells and particles suspended in a fluid. The method...

Fluorescence lifetime refers to the average time it takes for a fluorophore, a molecule that absorbs light at one wavelength and emits it at another, to return to its ground state after being excited...

Fluorescence lifetime imaging (FLIM) is an advanced imaging technique that provides information about the lifetime of fluorescence emissions from fluorophores within a sample. Unlike traditional...

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...

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...

Hyperchromic shift refers to an increase in the absorption of light, leading to a higher absorbance, often observed in certain chemical or biological substances upon undergoing a structural change....

Indirect time-of-flight (iTOF) is a method used in 3D imaging and depth sensing to measure the distance to an object based on the time delay between the emission of a light pulse and the detection of...

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 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...

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....

An experimental research technique by which absorbed or unabsorbed radiation is analyzed in order to characterize and determine material properties, concentration as well as behavior under the...

The laser damage threshold refers to the maximum level of laser intensity that a material can withstand without experiencing damage. It is a critical parameter in laser applications and is...

An instrument usually consisting of a very long interferometer, 3 to 800 m, and a laser light source for the study and measurement of strain, such as those formed by earth tides and gravitational...

A lumen is a unit of measurement used to quantify the amount of luminous flux, which is the perceived power of light. In other words, the lumen measures the total amount of visible light emitted by a...

A machine vision lens is a specialized optical lens designed for use in machine vision systems, which are used for automated inspection, measurement, and quality control in industrial applications....

A MEMS fiber optic switch is a microelectromechanical system (MEMS) device designed to selectively route optical signals between multiple fiber optic channels. These switches utilize miniature...

Modal bandwidth is a crucial parameter in optical fiber communication systems, particularly in multimode fiber (MMF) systems. It quantifies the ability of a fiber optic link to transmit data at high...

In optics, "mode beating" refers to an interference phenomenon that can occur in laser systems with multiple longitudinal modes. Longitudinal modes are specific electromagnetic field patterns that...

A specific form of phase shifting interferometry - commonly referred to as multiple wavelength phase shifting interferometry - this form of interferometry utilizes two short wavelengths to synthesize...

On-board optics refers to optical systems integrated into devices or platforms for various purposes, such as imaging, navigation, communication, and sensing. These systems are crucial in a wide range...

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....

An optical frequency comb is a tool used for measuring frequencies with extremely high precision. It is essentially a spectrum consisting of a series of discrete, equally spaced frequency lines, much...

An instrument that measures several optical parameters, such as optical power and wavelength, with a single measurement input.

Optical strain sensors are devices that utilize optical principles to measure the deformation or strain experienced by a material under mechanical stress. These sensors convert changes in strain into...

An optical testing instrument is a device or system used to evaluate and measure the performance, quality, and characteristics of optical components, systems, and devices. These instruments play a...