Calcium fluoride has high transmittance between ultraviolet and middle infrared (250nm~7um), so it is widely used in the manufacture of prisms, windows and lenses. In some applications with wide spectrum, it can not be used directly, especially it has small absorption and high laser threshold, so it is very suitable for application to excimer laser optics. In the system. Our company produces calcium fluoride lens or window, the diameter range is: 5~150mm, the surface precision is usually up to 40/20, the surface roughness can reach: lambda /10@633nm (the ratio of the thickness to diameter of the lens should be in accordance with the processing ratio).