Photonics Dictionary

An optical pyrometer that is equipped with a narrow bandpass filter to transmit a limited number of wavelengths to the sensing device.

Glass tinted with mixed oxides of neodymium and praseodymium that, unlike most solid materials, have absorption bands that are very narrow and that have very sharp areas.

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 nonabsorbing, multireflecting device, similar in design to the Fabry-Perot interferometer, that serves as a multilayer, narrow-bandpass filter.

A spectrophotometer that makes use of filters to isolate narrow bands of the spectrum.

The full width at half maximum (FWHM) is a measure used in various fields, particularly in spectroscopy, signal processing, and imaging, to characterize the width or extent of a distribution, peak,...

GaN (gallium nitride) distributed feedback (DFB) lasers refer to a specific type of semiconductor laser based on Gallium Nitride materials and designed with a distributed feedback structure. These...

An optical instrument used to isolate a narrow bandwidth of optical radiation using a diffraction grating as the dispersive element. See also monochromator.

X-rays of one frequency or a narrow band of frequencies.

Hyperspectral imaging is an advanced imaging technique that captures and processes information from across the electromagnetic spectrum. Unlike traditional imaging systems that record only a few...

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...

Hyperspectral resolution refers to the level of detail or granularity in the spectral information captured by a hyperspectral imaging system. In hyperspectral imaging, the electromagnetic spectrum is...

Infrared radiation absorbed by crystals as a result of the excitation of lattice vibrations in which ions having opposite charges move relative to one another. These vibrations take place in a narrow...

A filter that controls the spectral composition of transmitted energy partially by the effects of interference. Frequently, these filters are made up of thin layers of metals and dielectrics,...

The spectroscopic analysis of optical line shapes and frequency shifts, using the technique of light beating; i.e., the mixing of two narrowband optical components to produce an AC component in the...

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...

A micro-ring resonator is a compact optical device that utilizes the resonant behavior of light within a small ring-shaped waveguide structure to selectively enhance or filter certain wavelengths of...

Light consisting of a single wavelength or a very narrow band of wavelengths.

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...

The use of narrow bandpass filters and special photographic emulsions to discern features of a surface that would not be easily recognizable with regular black-and-white or color photographic methods.

Also referred to as a band-stop or band rejection filter; a notch filter is a filter that is designed to screen out a very narrow band of radiation by transmitting most wavelengths with little...

An optical filter is a device that selectively transmits or blocks specific wavelengths, or colors, of light. Optical filters are used to control the spectral content of light in various...

Also known as light beating. The mixing of two narrowband optical components to produce an AC component in the photocurrent at the optical difference frequency.

A means of achieving higher peak powers and more efficient harmonic generation by narrowing the pulse width and thus increasing the frequency bandwidth of the output of CW mode-locked lasers....

A nonlinear label-free imaging technique commonly used during surgical procedures for the visualization of collagen fibers and muscle tissue (myosin) with submillimeter resolution. During the...

Referred to as SWCNTs, these cylindrical nanostructures composed of a folded sheet of graphene can be used as near-infrared markers for small animal multiplex imaging. Emitting at different...

A combination spectrometer and bolometer that is designed to measure a narrow band of radiation from a star.

A multilayer filter that passes only a narrow band of wavelengths.

Supercontinuum refers to a broad spectrum of light that spans a wide range of wavelengths, typically from the visible to the near-infrared or even mid-infrared regions of the electromagnetic...

A thin layer of a substance deposited on an insulating base in a vacuum by a microelectronic process. Thin films are most commonly used for antireflection, achromatic beamsplitters, color filters,...

A multilayer antireflective thin-film coating, so called because its reflectance rises steeply at wavelengths above and below a narrow band at zero. The v-coat is particularly useful in high-power...

Volume Bragg gratings (VBGs) are specialized optical elements that consist of periodic variations in refractive index throughout the volume of a transparent material, typically a photosensitive glass...