A simple real-time method for checking parallelism between the two gratings in Talbot interferometry

摘要

A simple and practical detection method for the tilt-angles between the two non-parallel grating planes in the Talbot interferometry is proposed. It uses a pair of the cross-gratings and can simultaneously measure the two small angles with respect to the axes parallel to the line directions of the grating. The method is suitable not only for real-time measurement but also for automatic checking by digital Talbot interferometry based on the computer processing. The theoretical analyses coincide with experimental results.