In visible light a spectrometer can separate white light and measure individual narrow bands of color, called a spectrum. Spectrometer is a broad term often used to describe instruments that measure a continuous variable of a phenomenon where the spectral components are somehow. A spectrometer is a device used to measure the properties of light over a specific portion of the electromagnetic spectrum, often through processes such as absorption, emission, or scattering. It is primarily used to determine the concentration of a particular substance in a sample by measuring how. Strictly speaking, a spectrometer is any instrument used to view and analyze a range (or a spectrum) of a given characteristic for a substance (for example, a range of mass-to-charge values as in mass spectrometry), or a range of wavelengths as in absorption spectrometry like nuclear magnetic. Optical spectroscopy is a technique that is used to measure light intensity in the ultraviolet (UV), visible (VIS), near-infrared (NIR), and infrared (IR) range of the electromagnetic spectrum. The word “spectrum” refers to the range of wavelengths or frequencies of electromagnetic radiation, which includes visible light, ultraviolet (UV) light, infrared (IR). A spectrophotometer is a scientific instrument that measures the intensity of light as it passes through a sample solution.