A new lateral shear interferometer based on the Ronchi grating is proposed. The normal Ronchi test is impaired by multiple beam interference (Talbot effect). Furthermore, the fringe pattern is somewhat restricted by fringe number and orientation. The new shear interferometer suppresses the Talbot effect by spatial filtering and by using a second grating enables arbitrary fringe orientation and number.
© 1980 Optical Society of America
J. Schwider, "Single sideband Ronchi test," Appl. Opt. 20, 2635-2642 (1981)