Interferometer based on four diffraction gratings

Abstract

An interferometer based on diffraction gratings, used over their whole area, and designed to overcome some of the disadvantages of the four-mirror Mach-Zehnder arrangement is described. Its theoretical and practical assessment leads to the conclusion that, in comparison with the latter, it is remarkably inexpensive and insensitive to misalinement, though wasteful of light and subject to certain residual optical imperfections.