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The coating technology of optical lens is an important part of the whole optical system. Good coating technology can improve the refractive index, Abbe number, scattering, diffraction and chemical properties of the lens. Physical vapor deposition (PVD) technology is generally used in vacuum coating of optical films, including thermal evaporation, sputtering, ion plating and other methods. The optical lens before coating generally must be cleaned by centrifugal force cleaning machine and ultrasonic cleaning machine, but if you want to get ultra-clean matrix surface, you need to further use plasma cleaning, not only can remove the surface of the organic residue after centrifugal force cleaning and ultrasonic cleaning, but also can play a positive role in the post-coating technology.