Method of Controlling the Micro-and Nanoscale Displacements Based on Optical Correlation

The formation of a complex field in an optical correlator consisting of a set of phase gratings separated by layers of space is investigated. We found conditions when the redistribution of intensities in the output diffraction orders in such a correlator is very sensitive to a small transverse shift of the input interference pattern of light. Registration of changes in the angular spectrum can be used as an effective sensor to monitor small displacements, including the nanoscale range.