prism, Dove prism, Right Angle prism,Penta prism

Penta prism can deviate an incident beam without inverting or reversing to 90. The deviation angle of 90 is independent of any rotation of the prism about an axis parallel to the line of intersection of the two reflecting faces. It is commonly used in Plumb Level, Surveying, Alignment, Rangefinding and Optical Tooling.
prism, Dove prism, Right Angle prism,Penta prism