基于衍射光线追迹和波前再现的方法,建立了薄膜衍射主镜基底面形误差所引起波前误差的物理仿真模型。并以边缘褶皱面形和中心向外凸出球面面形两种典型的薄膜基底形变类型为例,分别研究了两种面形误差对衍射主镜成像质量的影响,讨论了这两种典型薄膜形变所引起的主要像差类型,分析了衍射主镜波前均方根误差、面形峰谷值与光学系统斯特列尔比(SR)的相互关系,为进一步研究薄膜衍射主镜的装配夹持和像差补偿提供了理论支撑。

A wavefront aberration model with respect to substrate deformation error of membrane diffractive lens is built by means of diffractive ray tracing and wavefront reconstruction method. Two typical cases of the substrate deformation errors, the edge wrinkle surface and the spherical surface with center outward structure, are demonstrated. Meanwhile, the influence of the deformation errors on related image quality is evaluated and the principal aberration type caused by the deformation errors is discussed. The relationship between wavefront root-mean-square aberration, surface peak-to-valley value and Strehl ratio (SR) is investigated. This work would be helpful in assembling membrane diffractive lens and compensating aberration in a real diffractive telescope system.