Right-angle Prisms

Right angle prisms are 45-45-90 degree prisms used to direct beams at 90 degrees by total internal reflection at the hypotenuse face, or as retro-reflectors. They are often preferable to an inclined mirror under severe acoustic or inertial loads, being easier to mount and deforming much less under mechanical stress. Prisms are made of BK7 or UV fused silica in a range of sizes and angle tolerances, uncoated or with HR or AR coatings.