Corner Cubes Prisms

Corner cubes have three mutually perpendicular reflecting surfaces forming the corner of a cube, with the entrance face perpendicular to the cube diagonal, so incident light is deviated by 180° back to its original direction independently of the angle of incidence. They are used in high precision applications, with lasers over very long distances and wherever orientation is difficult to control. Variants are made of BK7, UV fused silica and other materials in different diameters, uncoated, AR-coated or with metal-coated back surfaces, unmounted or mounted in rings.