空间引力波望远镜内部光场计算方法研究

Research on optical field calculation methods in the space gravitational wave telescope

在空间引力波探测系统中,望远镜系统出瞳处的复振幅光场分布仿真准确性密切影响着干涉测量的准确性和TTL噪声控制分析有效性,因此对其内部光场传输进行高精度衍射仿真计算十分必要。本文论证了采用基于矢量光线追迹的衍射积分算法建立仿真算法的必要性,结合离轴无焦四反望远镜模型进行了算法流程说明。基于该算法建立了仿真程序,带入望远镜系统设计参数,进行了波前计算精度的验证,并展示了矢量光场仿真计算结果。基于该系统模型,对输入高斯光场参数、元件表面复折射率两个因素对输出光场矢量特性带来的影响进行了仿真讨论。

In the space gravitational wave detection system,the accuracy of the complex amplitude field distribution simulation at the telescope exit pupil closely affects the accuracy of the interferometric measurement and impacts the effectiveness of TTL noise control analysis.Therefore,it is necessary to carry out the high-precision diffraction calculation for the field propagation.This paper demonstrates the necessity of the vectorial ray-based diffraction integral algorithm for simulation and illustrates the algorithm flow combining the telescope model.A computational model was established based on the algorithm.The telescope system parameters were substituted to verify the wavefront calculation accuracy,and the vectorial field simulation results were presented.Based on the system model,the effects of the input Gaussian field parameters and the complex refractive index on the output vectorial optical field characteristics are simulated.