Spectroscopy is the study of the interaction between matter and radiative energy of different types (electromagnetic, acoustic, ion flux, etc.). When we do not specify the nature of the radiative energy, we are talking about optical spectroscopy – the interaction between matter and light. Historically, spectroscopy originated through the study of visible light dispersed according to its wavelength, by a prism. Later the concept was expanded greatly to include any interaction with radiative energy as a function of its wavelength or frequency.
Spectroscopic data is often represented by an emission spectrum, a plot of the response of interest as a function of wavelength or frequency. Spectroscopy and spectrography are terms used to refer to the measurement of radiation intensity as a function of wavelength and are often used to describe experimental spectroscopic methods. Spectral measurement devices are referred to as spectrometers, spectrophotometers, radiometers, spectrographs or spectral analyzers. Optical spectroscopy is usually separated into two main measurement methods: radiometry and photometry. Photometry uses quantum methods of registration: photon counting, photon correlation, etc. Radiometry uses integral methods of registration of the parameters of the radiant flux: power and flux density, etc.
There are two particularly important specific cases of interaction between light and matter. These are photoluminescence and Raman spectroscopy. Photoluminescence is light emission from any form of matter after the absorption of photons. It includes fluorescence and phosphorescence. The main difference between them is in the value of the typical time constant of the photoluminescence process. The time constant of fluorescence is in the range from picoseconds (sometimes femtoseconds) to milliseconds, while for phosphorescence, the typical time is from milliseconds to seconds or even minutes. Photoluminescence gives us information about the characterization of crystalline materials such as semiconductors and polymers.
Raman spectroscopy is a spectroscopic technique used to observe vibrational, rotational, and other low-frequency modes in a system. Raman spectroscopy is commonly used in chemistry to provide a fingerprint by which molecules can be identified. Sciencetech has broad experience in designing and manufacturing of scientific systems for spectroscopy.
The Sciencetech modular principles in designing of optical devices allows us to create optical system of any complexity that fit any custom specifications. Most of the components are manufacturing by Sciencetech itself: Light sources, monochromators, sample chambers, data acquisition systems, and software. Some of the spectroscopic systems manufactured by Sciencetech are really unique and the best in their class. For example, Sciencetech’s Far Infrared THz System was chosen by the European Space Agency for reference THz measurements.