Interferometry's the technique of diagnosing the properties of two or more lasers or waves by studying the pattern of interference created by their superposition. The instrument used to interfere the waves together's called an interferometer. Interferometry's an important investigative technique in the fields of astronomy, fiber optics, engineering metrology, optical metrology, oceanography, seismology, quantum mechanics, nuclear and particle physics, plasma physics, and remote sensing. Rudime… (More on Interferometer)