Optical vortex tracking using standard deviation of phase maps with application in deformation analysis

Abstract

Optical vortices (OVs) are localized using a statistical phase map algorithm and used as markers to characterize the deformation of a loaded transparent sample. Numerical and experimental phase maps with OVs with aberration functions are propagated to axial planes and then processed to determine the change in positions of the OVs corresponding to the deformation. Calibration curves are generated to determine the aberration degree given the OV displacement. OV displacement increases as the frequency of aberration is increased; the limit of which would be until artifacts begin to appear. The advantage of the technique is that no phase unwrapping is needed as in conventional holographic deformation analysis.