Corner Cube prism has three mutually perpendicular surfaces and a hypotenuse face.  It operates on the principle of total internal reflection(TIR).  A beam entering the effective aperture is reflected by the three roof surfaces and emerges from the entrance/exit surface parallel to itself. This property is independent of direction of the retro-reflector, within acceptance angle limitations. 

For applications in which either the acceptance angle for TIR is exceeded, or the reflecting surfaces can not be kept sufficiently clean for TIR, a metal or dielectric coating can be applied to the reflecting surfaces. 

Optical glass prisms are available as off-the-shelf (stock) items or can be custom-designed to meet specific requirements. Standard prisms are pre-manufactured and readily available, catering to common applications and enabling quick deployment. Custom prisms, on the other hand, are tailored to meet the exact specifications of a particular application, including size, shape, material, and coatings.