多束部分相干光抑制光强闪烁效应的仿真实验研究

摘要

In order to restrain the scintillation effect in the course of laser transmitting through the at-mosphere, the relation between the laser coherence and the scintillation index was researched. First, the mathematic model correlating with laser coherence was established based on the generation mechanism of scintillation effect. Then, the laser was divided into four beams, and the coherence was destroyed. On this basis, the atmosphere turbulence emulation experiment device was made using the random phase screen as core element, and the far field spot scintillation index with different laser coherence was evalu-ated. Experimental results indicate that the scintillation index with four beams reduce about 75% in com-parison with single beam. So the availability of multiple partially coherent beams limiting laser intensity scintillation effect has been approved by the result of theory analyzing and experiment.%为了有效抑制激光大气传输过程中引起的闪烁效应,本文围绕照明光束相干性与闪烁指数关系展开研究。首先,明确闪烁效应产生机理,建立与光束相干性相关的数学模型。然后,采用偏振分光元件将出射激光分为4束,并破坏其相干性。在此基础上,以随机相位屏为核心元件构建大气湍流仿真实验装置,评估不同光束相干性条件下的远场光斑闪烁指数。实验结果表明,4束光照明的光斑闪烁指数比单光束照明降低了75%。理论分析及实验结果均证明了多束部分相干光在抑制光强闪烁效应方面的有效性。