Matsuda K
Appl Opt. 1980 Aug 1;19(15):2643-6. doi: 10.1364/AO.19.002643.
A lateral shear interferometer using twin three-beam holograms is described. In the interferometer two first-order diffracted light beams from the first hologram play the role of a beam splitter; the second hologram eliminates the effect of tilt. This interferometer has two advantages over the single three-beam hologram lateral shear interferometer: (1) it can be used for small f/No. lens tests; (2) any small aberration of he optical system of the interferometer can be canceled by using the second hologram. In this paper, shearing interferograms of lens aberration, of refractive indices around a flame, and of spouting gas are demonstrated.