关键词: 涡旋光, 拓扑荷数, 迈克耳孙干涉光路, 相位恢复

Abstract: Vortex beams exhibit extremely important applications in optical communication, optical trapping, and other fields due to the orthogonal properties between the light fields with different topological charge numbers. In particular, the topological charge number is an important parameter for describing the phase distribution of vortex beams. Controlling and detecting this number is thus the basis for information loading and extraction in vortex beam communication. In this study, the petalshaped interference patterns are obtained and used to recover the phase distribution of vortex beams and detect the topological charge number of vortex beams based on the Michelson interference optical path. The measurement results are basically consistent with the theoretical results. Furthermore, considering the system error caused by the pixel scale of the spatial light modulator, the local phase and topological charge number are corrected. This method is also used to detect fractional topological charge and double topological charge for complex vortex beams. This work provides a feasible method for phase recovery and information extraction in complex optical light field.

Key words: vortex beams, topological charges, Michelson interference optical path, phase recovery