基于多目标优化的低偏振像差离轴反射式天文望远镜设计方法研究

随着未来天文望远镜朝大口径、高像质的方向不断发展，偏振像差对望远镜成像质量的影响逐渐凸显。为充分发挥无遮拦离轴反射式望远镜在天文观测等领域中的优势，构建低偏振像差的离轴反射式望远镜非常必要。本项目提出基于多目标优化的低偏振像差离轴反射式望远镜设计方法，主要内容有：（1）分析离轴反射式望远镜中偏振像差分布特性及其与设计参数之间的关联机理，研究离轴反射式望远镜的偏振像差理论；（2）结合波像差理论和薄膜光学理论，构建表征偏振像差、波像差和光学效率等望远镜关键光学指标的目标函数；（3）将设计离轴反射式天文望远镜的约束条件和鲁棒性特点融入目标函数，使其成为搜索非支配解的重要驱动；（4）建立低偏振像差离轴反射式望远镜的多目标优化数学模型。本项目旨在创建一种低偏振像差离轴反射式望远镜的设计理论及方法，为实现超高像质的天文观测奠定技术基础，也可为设计其他低偏振像差光学系统提供参考。

Considering the future development of astronomical telescopes towards large aperture and high imaging quality, polarization aberrations are playing increasingly important roles in the performance of astronomical telescopes. In order to give full play to the advantages of off-axis reflecting telescopes in astronomical observations, it is necessary to study the design method of the off-axis reflecting telescopes with low polarization aberrations. In this project, a new method based on multi-objective optimization framework is proposed. The following will be studied: (1) The distribution of polarization aberrations in off-axis reflecting telescopes and its correlation with systemic parameters will be analyzed to obtain the polarization aberration theory in off-axis reflecting telescopes. (2) The merit functions about polarization aberrations, wavefront errors and optical efficiency will be found according to polarization aberration theory, wavefront error theory and thin film optics theory. (3) Tolerance sensitivity and constraint conditions will be analyzed and their merit functions will be characterized. (4) A model for designing the off-axis reflecting telescopes with low polarization aberrations based on multi-objective optimization method will be built. This project is dedicated to acquire the basic principles to design the off-axis reflecting telescopes with low polarization aberrations, which will play key roles in achieving astronomical observations that demand ultra-high imaging quality. In addition, this project will be helpful to design other optical systems with low polarization aberrations.