Optical Mirrors are used in optical instruments for light reflection. They have a smooth, highly polished surface to reflect light. The reflecting surfaces is usually treated with reflective optical coating materials.

The reflective coatings will vary depending on the application and the required wavelength range. Coatings include aluminium, silver, gold and dielectric.  Optical mirrors can be made from a variety of  materials depending on the application.

 Some materials include borosilicate glass (BK7); copper, used in high-power applications because of its high thermal conductivity; fused silica is suitable for use with moderately-powered lasers or changing environmental conditions; nickel for applications where resistance to both thermal and physical damage is required.