United Photonics Technology, Inc.-ISO9001 Company Mirror Mirror is a reflecting surface that forms an image of an object when light rays coming from that object fall upon it. Usually mirrors are made of plate glass, one side of which is coated with metal or some special preparation to serve as a reflecting surface. UPT offers dielectric coated mirrors and metal coated mirrors which are made of substrate such as Bk7, K9, Fused Silica, CaF2, Sapphire. Specifications: Material: BK7 Grade A Optical Glass or other material, Typical Diameter (�¦mm) 8.0, 10.0, 12.7, 15.0, 20.0, 25.4, 30.0, 50.8 Typical Thickness (mm) 2.0, 3.5, 5.0, 6.5 Diameter Tolerance (mm) +/-0.2 (General), +0.0/-0.02 (High Precision) Thickness Tolerance (mm) ±0.2 (General), ±0.05 (High Precision) Clear Aperture >80% (Small Size), >95% (Large Size) Parallelism 6 min. (General), 3 sec. (High Precision) Surface Quality 80/50 (General), 10/5 (High Precision) Flatness (per 25mm@633nm) (General), /10 (High Precision) Bevel (face width x 450)