This paper describes a method for testing a right angle prism, or any other optical component having a right angle, to subarcsecond accuracy. The method makes use of Haidinger fringes and is simple to use. Unlike autocollimation ...

A rotational shearing interferometer is a modification of the Michelson’s interferometer to obtain the spatial coherence of the light waves. It is mainly used for obtaining diffraction limited images of astronomical ...