Investigations on the measurement of freeform optical wavefront using a holo-shear lens

A Shearing interferometer provides wavefront slope information in the direction of shear. If it is used to test non-rotationally symmetric wavefronts, a lateral shearing interferometer must produce shear in two orthogonal directions. In this paper, we have presented the application of the holo-shear lens to test the freeform (non-rotationally symmetric) wavefront. Experimental results were compared with the computer-generated hologram (CGH) null in the Mach-Zehnder interferometric configuration, and deviation is less than a quarter wave. The method is simple, robust, less intricate, and cost effective.