etalon

science

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June 26, 2026

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An etalon is a type of optical interferometer used for precise scientific measurements. It consists of two parallel, highly reflective plates separated by a fixed distance. When light passes through an etalon, it undergoes multiple reflections between these plates. This process creates interference patterns, specifically very narrow and sharp fringes, which are valuable for analyzing the fine structure of spectrum lines and determining wavelengths with high resolution. The etalon's design allows for detailed examination of light, aiding in fields like spectroscopy and metrology.12

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optical interferometer
…strictly parallel plates called an etalon. Because of the high reflectivity of the plates of the etalon, the successive multiple reflections of light waves diminish very slowly in intensity and form very narrow, sharp fringes. These may be used to reveal hyperfine structures in line spectra, to evaluate the widths…
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…strictly parallel plates called an etalon. Because of the high reflectivity of the plates of the etalon, the successive multiple reflections of light waves diminish very slowly in intensity and form very narrow, sharp fringes. These may be used to reveal hyperfine structures in line spectra, to evaluate the widths…
Read More