Non-mechanical photoelectric tracking technology using liquid crystal phased array

Abstract

A non-mechanical photoelectric tracking technology based on liquid crystal phased array was proposed. A mathematical model of a liquid crystal phased array photoelectric tracking closed-loop system was established. The laser emits incident light of a specified wavelength. Incident light enters the liquid crystal phased array through polarizers, waveplates and other optical devices. The difference between the deflected beam and the incident light is received with the camera after the liquid crystal phased array. The liquid crystal phased array adopts voltage control to achieve the deflection of the incident beam and achieve the purpose of accurate tracking. The motion state of the simulated target is analyzed and a modern control algorithm is designed. Subsequent simulations and experiments were conducted. Simulation results show that the dynamic tracking error of the liquid crystal photoelectric tracking system is better than 18μrad. Its closed-loop bandwidth exceeds 2.3HZ. On the basis of the above work, a desktop demonstration experiment platform was built. Experimental results show that the dynamic tracking error of the liquid crystal tracking control system is better than 20μrad, which has good robustness.