基于折射率界面厚度和本征正交分解的三维非均匀固体媒质光传输算法研究

Study on the optical transmission effect of three-dimensional inhomogeneous solid medium is important for enhancing the terminal guidance precision of high-speed aircraft. Based on numerical simulation, this study includes the following parts: (1)establishing the computational model of the complex thermal environment for three-dimensional inhomogeneous solid medium, (2)reconstructing refractive index field of three-dimensional inhomogeneous solid medium based on refractive interfacial thickness concept and proper orthogonal decomposition, (3)investigating the numerical simulation and algorithm for the optical transmission through three-dimensional inhomogeneous solid medium, (4)analyzing the confidence level of the optical transmission algorithm for three-dimensional inhomogeneous solid medium, and (5)comparing the optical transmission result of the reconstructed refractive index field with that of the original refractive index field for three-dimensional inhomogeneous solid medium.. The purposes of this study are (1) to reduce the refractive index information required in the optical transmission research of three-dimensional inhomogeneous solid medium, (2) to disclose the influences exerted by the complex thermal environment on the imaging quality of three-dimensional inhomogeneous solid medium, (3)and to solve the optical transmission problems of three-dimensional inhomogeneous solid medium at different incident angles. This study can also provide the theoretical basis and guidelines for improving the terminal guidance precision of the high-speed aircraft, and imaging precision of the satellite-earth detection system and the proximity space-to-ground detection system.

三维非均匀固体媒质光传输效应研究在提高高速飞行器末制导精度方面非常重要；采用数值仿真方法，重点研究内容包括：(1)三维非均匀固体媒质复杂热环境建模；(2)基于折射率界面厚度和本征正交分解的三维非均匀固体媒质折射率场重构；(3)三维非均匀固体媒质光传输数值仿真与算法研究；(4)三维非均匀固体媒质光传输算法置信度研究；(5)三维非均匀固体媒质重构折射率场和原折射率场光传输仿真结果比对研究。预期目标为：有效减少三维非均匀固体媒质光传输研究所需折射率场信息量；揭示复杂热环境对三维非均匀固体媒质成像质量的影响规律；解决不同入射角度下三维非均匀固体媒质光传输问题。该课题的研究成果将为提高高速飞行器末制导精度提供理论基础和指导方法，也可用于提高星地探测光电系统和近空间高速飞行器光电对地成像系统的成像精度。

头罩/侧窗的光传输效应会引起目标像的偏移、抖动和模糊，进而影响了高速飞行器对目标的探测、跟踪与识别能力，因此研究复杂热环境下三维变折射率固体介质（头罩/侧窗）光传输效应，对提高高速飞行器红外成像探测精度具有重要意义。此外，三维变折射率固体介质巨量的折射率场数据给三维变折射率固体介质光传输效应研究带来了不便，因此研究减少三维变折射率固体介质折射率场数据量的折射率场重构方法，对三维变折射率固体介质光传输效应研究具有重要意义。.本课题主要研究内容包括：.（1）建立了复杂热环境下三维变折射率固体介质热响应计算模型，且运用该模型确定了复杂热环境下高速飞行器头罩和侧窗温度场、应力场、应变场和形变场的分布规律。.（2）建立了复杂热环境下三维变折射率固体介质折射率场计算模型，计算了高速飞行器头罩和侧窗的折射率场。提出了基于折射率界面厚度的三维变折射率固体介质折射率场重构方法，对高速飞行器侧窗的折射率场进行了重构；提出了基于高阶奇异值分解的三维变折射率固体介质折射率场重构方法，分别对高速飞行器头罩和侧窗的折射率场进行了重构。.（3）建立了光线倾斜入射情况下非规则形状三维变折射率固体介质光传输模型，分析了高速飞行器头罩和侧窗的光传输效应对高速飞行器光学系统成像质量的影响。研究了基于折射率界面厚度和基于高阶奇异值分解的三维变折射率固体介质折射率场重构方法对三维变折射率固体介质光传输仿真软件运行效率的影响。.（4）通过三个算例分析了光传输模型的准确度，然后将光传输模型获得的数值计算结果与电弧风洞实验结果进行了比对。数值仿真结果和实验结果均验证了光传输模型的正确性。