Photonics Dictionary

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...

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...

That part of the science involved in the study of the theory and interpretation of spectra that uses the unique characteristics of the laser as an integral part in the development of information for...

A type of fluorescence spectroscopy in which an excimer laser, a dye laser and a frequency-doubling device are used to detect polycyclic hydrocarbon atoms to a part-per-billion level.

A pump-probe technique whereby a single wavelength source may be used in order to excite a given sample to determine electronic transitions.

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 spectrograph using a prism that has an internally reflecting surface and that serves as a constant deviation prism.

The method that, by measuring the absorption along an atmospheric path at wavelengths ranging from two to a continuum, can determine pollution concentrations of gases.

The analysis of structural and molecular dynamics caused by low temperature.

A method of studying the chemical and physical properties of atoms and molecules (typically living tissue and chemical samples) by exploiting the magnetic properties of their atomic nuclei when an...

Technique in which the polarization rotation of light, and its relationship to the magnetic field strength can be analyzed and related to various experimental parameters when passed through a...

An electron system using the effect of a constant magnetic field on electron paths to differentiate electrons that have varying velocities for the accurate measurement of the energies and intensities...

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 that uses electromagnetic fields to separate electrically charged particles according to their masses. As a beam of charged particles is passed through a mass spectrograph, the result is a...

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 instrumental technique that utilizes the mass-to-charge ratio of charged particles as recorded from a mass spectrometer in order to determine the mass of a particle as well as the chemical makeup,...

An instrument that uses electromagnetic fields to sort out the relative masses of atoms and molecules.The same way an optical spectroscope uses a prism to separate light into its various wavelengths,...

A microspectroscope equipped with a sensing and recording device, such as a camera, to measure the spectrum formed by microscopic samples.

A specialized spectrophotometer for use through a microscope on very small areas of an object.

A system composed of a prism spectroscope and compound microscope to provide the visual comparison of two spectra simultaneously -- that of the sample focused by the microscope and that of the...

A method of spectral analysis in which some property of the sample is varied and the corresponding change is measured. The change is induced by a repetitive perturbation such as an electric field,...

Spectrum analysis concerned with the spectra formed by transitions in molecules.

Spectroscopy characterized by the Mossbauer effect - recoilless emission and absorption of nuclear gamma radiation- which investigates miniscule changes in the energy levels of atomic nuclei in...

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...

The recording and mathematical analysis of all spectral intervals of the spectrometer simultaneously.

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 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...

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....

That branch of spectroscopy that applies to the study of interactions between energy and atomic nuclei. The simultaneous application of a strong magnetic field and the radiation from a...

A chemical detection technique used to measure molecules that have a magnetic dipole moment. The analysis is directed to nucleuses which have a quadrupole moment which leads to an asymmetric electric...

In dry etching, a method of characterizing the composition of solid materials such as metal. Atoms in the OES technique are excited by energy that comes from a spark formed between the sample and an...

The spectroscopic study of the radiation emitted by the lifetime of phosphorescence.

A method for obtaining the optical absorption spectra of solids, semisolids, liquids and gases. PAS is inherently insensitive to reflection or scattering from the sample, analyzes opaque samples and...

A spectroscopic process that detects and analyzes the discharge from an extrinsic surface with less than bandgap light. This method may determine the extrinsic surface-state energy levels of a...

A system that consists of a spectrophotometer with a photoelectric detector for measurement of radiant energy.

Spectroscopy used to study the concentration, diffusion and Brownian motion of small particles suspended in a fluid by measuring dynamic fluctuations of light that is scattered or fluoresced by the...

A method of measuring complex sequential photosynthetic reactions by varying the pulse time and wavelength of light generated by a combination of argon-ion and dye lasers.

A spectrograph used to detect radiation in the range of the ultraviolet in the electromagnetic spectrum. It is made up of quartz because that material, unlike regular glass, is not opaque to the...

Raman spectroscopy is a technique used in analytical chemistry and physics to study vibrational, rotational, and other low-frequency modes in a system. Named after the Indian physicist Sir C.V. Raman...

An instrument that spectrally analyzes the flux reflected from a material. The reflected flux may be total, diffuse or specular. Often the instrument measures the reflectance factor instead of the...

A solar spectrograph that uses long focus concave mirrors as its collimator and camera element.

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...

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 type of ultrasensitive laser spectroscopy that can detect quantities as small as a single atom of some substances and that can differentiate between isobars of different elements.

A spectroradiometer having a means to scan different regions of the light spectrum, providing simultaneous representations of amplitude vs. wavelength of the spectrum.

The method of determining the energy distribution of high-speed charged particles by the luminous effect formed when the particles strike a material.

An advanced technique that allows the detection of one molecule within a crystal or a cell through optical excitation. Single-molecule spectroscopy (SMS) can image at subwavelength scales, down to a...

A technique for observing the decay of light emissions from sources following their pulsed excitations, based on recording the arrival time of the first photoelectron after excitation. After many...

Spatially offset Raman spectroscopy (SORS) is a technique that extends traditional Raman spectroscopy by incorporating measurements at different spatial offsets. This method allows for the selective...

Surface-enhanced Raman spectroscopy (SERS) is an analytical technique that combines the principles of Raman spectroscopy with the enhancement provided by nanostructured metallic surfaces. Raman...