Spectrometer

A spectrometer is a broad class of scientific instrument used to measure and analyze the spectrum of a physical quantity, most commonly the intensity of light or other electromagnetic radiation as a function of its wavelength or frequency, though the term is also applied to instruments that measure spectra of mass, as in mass spectrometry, or of other physical properties. The general principle traces back to the development of the spectroscope in the early nineteenth century by scientists including Joseph von Fraunhofer, who first systematically catalogued the dark absorption lines in the solar spectrum, and to the subsequent work of Gustav Kirchhoff and Robert Bunsen in the 1850s and 1860s establishing the connection between spectral lines and the chemical elements that produce them, which made spectroscopy a fundamental analytical technique. Since that foundational period, spectrometers of many specialized designs, including the mass spectrometers, infrared spectrometers and other specific spectrometer types used across chemistry, physics, astronomy and biology, have become some of the most widely used instruments across the whole of science, wherever a researcher needs to identify a substance or determine a physical property from the way it interacts with radiation or particles across a range of energies.