Generation of arbitrary vector vortex beams based on the dual-modulation method.

A dual-modulation method that combines a liquid crystal on silicon spatial light modulator with an S-waveplate and a biplate consisting of double quarter-wave plates (DQWPs) or double half-wave plates (DHWPs) is proposed. The method is used to realize the phase and polarization dual modulation of an incident laser beam. This study focuses on the generation of an arbitrary vector vortex beam (VVB) based on the proposed dual-modulation method. The phase and polarization transformation effects of the proposed method are theoretically derived using the Stokes-Mueller matrix algorithm. Correspondingly, an experimental configuration is constructed to generate arbitrary VVBs, and correlation analyses are carried out to quantitatively evaluate the quality of the generated VVBs. The results indicate that the correlation coefficients of the generated VVBs can reach more than 0.94 whether the biplate in the experimental configuration is DQWP or DHWP.