Research on beam control technology based on a phase spatial light modulator

The nonmechanical servo-controlled liquid crystal spatial light modulator (LCSLM) can modulate the wavefront phase in real time to achieve beam deflection by controlling the voltage loaded on each pixel. The beam deflection control ability is verified based on the Fresnel lens model and the blazed grating model. Including the relationship between deflection distance, diffraction efficiency and different model parameters, when the incident light wavelength is 1550 nm, the maximum deflection angle that can be achieved by the x-axis or y-axis is 6.96° (±3.48°), and the beam can be aligned with the two-dimensional plane offset. Aiming at the high-speed, sensitive, precise and large-angle scanning application requirements of the beam, a light wavefront phase adjustment algorithm based on the LCSLM is proposed. The phase conversion model is established by calculating the phase that needs to be compensated, and the beam control process is satisfied. The LCSLM-based beam is designed and constructed with a deflection and scanning experimental system, and the experimental results show that the light spot at any position in the light field can be flexibly shifted and controlled within a 360° recieving field of view. This research has important application value in the fields of free-space wireless optical communication, agile beam control, nonmechanical beam capture, aiming and tracking.