Prisms

Simplest and most cost effective prism for 90° beam deviation. Also for 180° deviation with lateral displacement. At 180° reflection, the image is reversed. The accuracy of the 90° deviation angle depends on the orientation of the prism – the beam can be directed in both planes. At 180° reflection, the beam can only be directed in the plane perpendicular to the lateral deviation. The 180° angle is determined by the precision of the prism.

A Dove prism does not change the direction of propagation of an incident light beam, but the image is rotated by 180°.

Designed for a beam deviation of 90°. The image has the opposite orientation to the right angled prism. The 90° deviation angle is determined by the precision of the prism – the beam can not be directed by the orientation of the prism into the 90° direction.

Deflects a beam by 180°, regardless of the orientation of the optic. A beam that is more narrow than the entrance pupil and not centered on the optic is shifted laterally. The image is inverted and mirrored. Retroreflectors can be solid or hollow.

Same 90° beam deviation function as the right angle prism, except that the image is mirrored.

A variation of the pentaprism with two output beams. The second beam is neither deflected nor moved laterally. The power of the input beam is split between the two output beams.

Essentially a window with non-parallel optical surfaces. The angle between the surfaces determines the angular deviation. Used for beam direction. A beam that enters with normal incidence can be directed by turning the prism over the lateral surface of a cone.