An Ion Beam Figuring machine allows a contactless polishing process. A small beam of positive ions (Argon) is projected against a substrate surface. Ions produce a chain collision with the atoms that allows material to be extracted in a controlled way. Before g to carry out the process, the surface must be measured with an interferometer, which will allow the generation of a map of action on the surface.

With this process we can obtain very high quality polishing results but it is slow process. Ion Beam Figuring is very useful for high-precision edge finishing, spatial optics, and optical elements working with high-power lasers.