Most optical spectrometers share four key components arranged in sequence: an entrance slit, a collimator, a dispersive element, and a detector. Each plays a specific role in turning a jumble of wavelengths into a clean, measurable 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. Spectrophotometers are used to analyze the optical properties of a sample by shining a beam of light into it. Using this, they can determine what material created the light. The core principle is simple: different wavelengths of light behave differently when they pass through a prism. A spectrometer splits light into colors to show what materials are made of by measuring light's intensity and wavelength.
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