Design of out-of-plane scanning linearization drive for waveguide beam scanner based on dual-frequency liquid crystal

Liquid crystal (LC) cladding waveguides, when used as a platform for non-mechanical beam scanning, show great potential for applications in LiDAR and free-space optical communications. Elastic recovery of the LC director deflection after voltage removal in most nematic LCs is slow and nonlinear, directly impacting scanner device performance. We present a linearized driving optimization method for beam scanners based on dual-frequency LC (DFLC), design a nonlinear composite driving waveform containing alternating low-frequency (<1 kHz) and high-frequency (>10 kHz) driving signals, and demonstrate high-speed and linear control of the out-of-plane beam deflection. Experimental results show that for a low driving frequency of 700 Hz, the out-of-plane deflection linearity reaches 0.994, the angular loss is 33.3%, and a single unidirectional scan takes 357.14 μs. This study provides an innovative solution and practical method to implement fast, linear one-dimensional non-mechanical beam scanning.