A radial shearing interferometer with two equispaced circular gratings is described for obtaining a constant radial displacement of the test wavefront. The procedure for the fringe analysis is shown by applying the Fourier transform method to the circular fringe pattern for precisely obtaining the differentiation of the test wavefront. A novel method is also shown for holographically making the equispaced circular gratings by using a cylindrical mirror and a collimating lens. It is shown that the deflection and misalignment of the gratings will not appear in the interferogram by using the holographic production method.
© 1989 Optical Society of America
Original Manuscript: May 2, 1988
Published: August 15, 1989
Qing-Shin Ru, Nagaaki Ohyama, Toshio Honda, and Jumpei Tsujiuchi, "Constant radial shearing interferometry with circular gratings," Appl. Opt. 28, 3350-3353 (1989)