Interferometer

n. instrument which uses interference between rays of light to measure wavelengths (Optics)

Interferometry is the technique of superposing (interfering) two or more waves, to detect differences between them. Interferometry is applied in a wide variety of fields, including astronomy, fiber optics, optical metrology, oceanography, seismology, quantum mechanics and plasma physics.
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Noun
1. any measuring instrument that uses interference patterns to make accurate measurements of waves
(hypernym) measuring instrument, measuring system, measuring device

n. interferometer, instrument which uses interference between rays of light to measure wavelengths (Optics)

n. interferometer, instrument which uses interference between rays of light to measure wavelengths (Optics)