A Optical Mirror Lens (Reflector) is an optical element that operates based on the law of reflection and is mainly used for beam turning, interferometry, imaging or illumination. The characteristics of a mirror depend on the optical coating, substrate and surface quality. The standard process for production is to coat a highly polished substrate material. The properties of the optical mirrors produced will vary depending on the materials and processes used for the substrate material and coating. Common substrate materials include N-BK7 optical glass, fused silica, float glass, etc. Optical coating determines the reflectivity and stability of the mirror, it is the most critical component of the mirror, the mirror film is usually made of metal materials or dielectric materials.