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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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)

An instrument that uses the principle of interference of electromagnetic waves for purposes of measurement. Note: Interferometers may be used to measure a variety of physical variables, such as displacement (distance), temperature, pressure, and strain.