Corner Cube Retroreflectors

BK7 or UVFS Corner cube retroreflectors designed to deviate incident light by 180 degrees independently of an angle of incidence.

These prisms have 3 mirror surfaces making angles of 90 deg to each other, juxtaposed to form the corner of a cube with the entrance face perpendicular to cube diagonal.
All beams, despite of incident direction, are reflected back to the original direction. Corner cubes are used in high precision applications or with lasers over very long distances.