spectromètre

A spectrometer is an instrument used to measure the properties of light over a specific portion of the electromagnetic spectrum. Its primary function is to separate light into its constituent wavelengths or frequencies and to measure the intensity of light at each wavelength. This separation is typically achieved using a dispersive element such as a prism or a diffraction grating. By analyzing the spectrum of light emitted or absorbed by a substance, scientists can deduce information about its chemical composition, physical state, and other properties.

Spectrometers are employed across a wide range of scientific disciplines and industrial applications. In chemistry, they are used for identifying unknown compounds, determining concentrations, and studying chemical reactions. Astronomers use spectrometers to analyze the light from stars and galaxies, providing insights into their composition, temperature, and motion. Materials science utilizes spectrometers to characterize the optical properties of new materials and to detect defects. In medical diagnostics, certain types of spectrometers can analyze biological samples to detect diseases. Environmental monitoring also benefits from spectrometers, which can identify pollutants in air and water.

The fundamental components of a basic spectrometer include a light source, a sample holder, a dispersing element (like a prism or grating), and a detector. The light source illuminates the sample, which then absorbs or emits light. The dispersing element separates the light into its different wavelengths, and the detector measures the intensity of light at each wavelength, producing a spectrum. Different types of spectrometers exist, optimized for specific wavelength ranges (e.g., ultraviolet, visible, infrared) or measurement techniques.