为了实现太赫兹探测系统快速控制、逆向聚焦、长距离和大范围扫描等功能,基于共焦Gregorian 反射系统(CGRS),采用ZEMAX光学仿真软件对光路进行仿真分析.首先,理论计算并确定该系统中主要反射镜的参数,予以建模;在此基础上,进行光路仿真、分析结果和计算误差.经分析知,该系统能够实现1.74m扫描范围内的25m远距离探测;并且调制传递函数接近衍射极限,成像良好.最后,利用高斯光束分析光信号在光路中传播的能量损耗情况,即当输入辐照度为63.6mW/mm2时,可以得到14.6mW/mm2的辐照度输出,为实际系统光源和探测器的选择提供了理论依据.

In order to achieve rapid control,reverse focus,long-distance and large-scale scanning of THz detection systems,the optical path was simulated and analyzed with the optical simulation software-ZEMAX based on the cofocal Gregorian reflection system.The main parameters of the reflecting mirrors wre calculated,and confirmed,based on which,optical simulation,results analysis and error calculation were performed.It is achieved 25m remote sensing in 1.74m scanning range,and the MTF transfer function is close to the diffraction limit.Finally,the energy losses of light signals propagating in the optical path were analyzed with Gaussian beam,and 14.6mW/mm2 output irradiance was obtained when the input irradiance was 63.6mW/mm2.