Photonics Dictionary

A kind of spectrograph in which some form of detector, other than a photographic film, is used to measure the distribution of radiation in a particular wavelength region.

A high-contrast transparency of the gas sought, or an array of exit slits that correlates with some features of the spectrum. No standardized formula for positioning, number or thickness has been...

An atomic absorption spectrometer (AAS) is an analytical instrument used to determine the concentration of specific chemical elements in a sample by measuring the absorption of light at...

An instrument for the detection of the energy distribution of b-particles and secondary electrons.

A device designed to measure crystal properties by analysis of crystal diffraction.

A small mass spectrometer, with a limited mass range, equipped with an analyzer to generate a cycloidal-path beam of the sample.

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.

A mass spectrometer utilizing both radial electrostatic and magnetic field analyzers to improve the focusing and increase resolution.

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...

An instrument using a Michelson interferometer, a beamsplitter, two plane mirrors and a detector to give Fourier analysis of the detector signal to provide the desired spectrum.

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...

An instrument used to detect and measure the energy distribution of gamma rays. It has been used to chart the radioactivity at the lunar surface.

A spectrometer that uses a grating to diffract light into specific wavelengths.

Also known as the Bragg spectrometer. A system used for the x-ray analysis of crystal structure. In the instrument, a homogeneous beam of x-rays is directed on the known face of a crystal and the...

Instrument that uses absorption spectroscopy to detect gases in planetary atmospheres. Dispersed incoming radiation is transmitted to one or more sampling elements, or masks, before reaching the...

A device used to measure the masses and relative concentrations of atoms and molecules. It utilizes the Lorentz force generated by external magnetic field on a moving charged particle, in which the...

An instrument that contains a spectrograph with a grating in which an array of slits, in place of a photographic plate, is arranged according to the lines of the sample to create an illustration of...

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....

A device employed to identify toxic agents lingering on the ground or in the air from up to three miles away, by using laser beams to detect infrared light-absorption patterns that can be analyzed to...

A terahertz spectrometer is a scientific instrument used to measure and analyze the properties of materials in the terahertz frequency range, typically spanning from about 0.1 to 10 terahertz (THz),...

A magnetic-deflection mass spectrometer that has an electrostatic field placed perpendicularly to its magnetic field, permitting both spatial mass dispersion and perfect double focusing in the plane...

A spectrophotometer designed for use in the 200- to 380-nm range of the electromagnetic spectrum and equipped with a calibrated scale to determine wavelength.

Also known as UV-VIS spectrometer, a device that measures the absorbance, reflectance or transmittance of light in the ultraviolet or visible wavelengths absorbed, reflected or transmitted. Commonly...

An instrument that measures the wavelengths of an x-ray spectrum by the diffraction of x-rays from a crystal with a given lattice spacing.

An instrument designed to produce an x-ray spectrum of a material as an aid in identifying it. This technique is particularly useful when the material cannot be broken down physically.

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...

A detector-Dewar assembly typically refers to a combination of a detector and a Dewar flask used in scientific instruments, particularly in the field of infrared spectroscopy or other applications...

A spectrometer equipped with polarizing prisms and retardation plates that is used in the analysis of elliptically polarized light, mostly in the study of thin, evaporated films.

The entrance slit, also known simply as the slit, is an essential component in optical instruments such as spectrometers and monochromators. It is a narrow opening or aperture through which light...

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 multiple-beam interferometer, usually consisting of two flat plates, with high reflective ability. The plates are set parallel to one another by spacers so that lightwaves may bounce back and forth...

The spectroscopic analysis of interference patterns using a monochannel spectrometer, spectrograph or multichannel spectrometer with a Fabry-Perot interferometer to record the fringes.

The signal-to-noise ratio (SNR) obtained with a Fourier transform spectrometer when detector noise prevails, which exceeds the SNR of a scanning spectrometer in the same time by a factor proportional...

An interferometer spectrometer designed to measure thicknesses of thin films or layers by recording the interferogram and by having a computer within the instrument to establish the distance between...

The study of flames by means of a laser emitting blue light and a spectrometer to measure the green fluorescence created by the flame chemistry.

A spectrometer or autocollimator used to measure prism angles.

A grating beamsplitter is an optical device that utilizes the principles of diffraction to split a beam of light into multiple beams, often redirecting them at specific angles. It is based on the...

A small mass spectrometer used to find leaks in a vacuum system by detecting the presence of helium. Using a magnetic deflection device that is permanently tuned to helium, it is capable of detecting...

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,...

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...

An image intensifier, also known as an image intensification tube or image intensification device, is a specialized electronic device used to amplify low-light-level images to make them visible to...

A spectroscopic technique in which an excitation band absorbs laser energy resulting in an electronic transition. The isotopic species may then be measured using a time of flight mass spectrometer....

The higher throughput obtained with an FTIR device compared with traditional spectrometers that need slits to achieve resolution. The advantage differs according to wave number and resolution.

A method of analysis in which a pulsed laser beam is used to heat a particle, producing a plasma, or laser spark. As the plasma cools, optical energy characteristic of the elements in the plasma is...