提出并设计了一个采用液晶空间光调制器(LCSLM)作为光束动态偏转器件的无机械光束扫描系统,实现了光束的方向和强度的可编程控制,解决了远场任意图形的激光光束动态逼近问题。逼近方法采用纯相位调制技术和傅里叶迭代优化算法结合的衍射图形相位优化设计方法。介绍了点阵图形发生原理并给出实验装置图。实验结果显示,用该方法产生的二维阵列式光束,其光斑强度偏差度小于8%, 图形发生响应时间小于100 ms,该实验结果能够满足多光束准确动态偏转的要求。该系统具有精确、响应快、无机械惰性等特点,在激光寻的、制导以及多目标威胁预警和反击中有着重要的研究价值。

A non-mechanical beam steering system is proposed and designed to resolve the problem of approaching the far-field diffractive pattern with laser beams. A beam steering method based on the phase only modulation with a liquid crystal spatial light modulator (LCSLM) is studied and described to control the light beams programmably. The Fourier iterative optimal algorithm is adopted to design the optimal phases approaching the expected far-field diffractive pattern. The schematic diagram and the experimental set-up are given. Results show that the method can generate 2-D spots arrays with the intensity error rate less than 8%. The response time of generating the dynamical diffractive pattern is less than 100 ms. With the merits of lightness, precision and quick response, this scanning system is of value in the fields of multi-object tracing, laser guiding and multi-object defense.