| As a non-mechanical beam deflection technique phased array which generates a beam with a good feature of precise, high-speed and sensitive. When liquid crystal phase modulator used as an optical phased array, it has the shortcomings of little beam deflection range and low efficiency. In response to this limitation, the angle amplification technology now is generally based on multi-stage cascade, in order to fine scan the angle after zooming based on liquid crystal optical phase array(LCOPA), there is often a condition of oblique incidence, the impact on the performance of the beam deflection analysis yet seen. In this paper, based on the study on LCOPA, we carried out the following work:1) Analyzing the fundamental wave control principle of LCOPA. Based on diffraction theory, we established the wave control model. With on the use of porous interference model we obtain a more convenient way to solve the far-field intensity distribution.2) Based on crystal elastic deformation theory, the liquid crystal director distribution model is established. With the help of Matlab, numerical simulation has been done to get the actual phase modulation distribution of LCOPA. Simulation analyzed the impact of the electrode edge effect and fly-back zone actually exist. Optimization of electrode voltage is proposed to get a better phase distribution.3) The effect on phase modulation distribution and beam deflection angle caused by oblique incidence was analyzed. Based on the correction of normal incidence model, the beam deflection performance under oblique incidence was analyzed through simulation.4) Design and set up an experimental platform to test the actual wave control performance of LCOPA under oblique incidence. Test results show that the oblique incident angle larger than 10°will have great impact on the deflection angle and efficiency. There is a need of electrode voltage correction combine with specific incidence angle. |
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