To enable the real-time traceability of measurements of the modulated phase distribution produced by a liquid crystal optical phased array (LCOPA), a spatial high-resolution phase measurement method based on optical combs, which combines spatial chirp and dual-comb interferometry techniques, is proposed herein. Theoretical simulation analysis is conducted to study the influence of the parameters of the grating and optical comb light source on the system''s spatial resolution and measurement field of view. Theoretical simulation results show that the field of view measured using this method can reach more than 100 mm, and the spatial resolution is better than 2 μm. Further, experimental results show that this method can enable the rapid measurement (microsecond timescale) of the modulation phase distribution generated by a multichannel LCOPA driving electrode. Thus, the proposed method is expected to provide an effective way for the development and performance evaluation of LCOPA devices.