Optical element smoothness improving method based on classical polishing

The invention provides an optical element smoothness improving method based on classical polishing. The optical element smoothness improving method comprises the following steps that S1, rough grinding forming is conducted; s2, accurate grinding: removing a crack layer left by rough grinding; s3, polishing: sequentially polishing the two mirror surfaces by adopting a classical polishing method, so that the degree of finish reaches VII, and other indexes except the degree of finish all meet the design requirements; polishing red cloth adheres to the polishing die, polishing liquid is added to the polishing red cloth, manual polishing is carried out, the degree of finish is superior to the IV level, and the polishing liquid is single crystal diamond liquid; the optical element is made of phosphorus crown glass or calcium fluoride crystals. According to the method, the surface smoothness of the phosphorus crown glass and the calcium fluoride crystals can be improved, the smoothness improving effect is very good,