基于表面自由曲面和视场的扩展过程，设计具有超宽视场的离轴三镜系统

songshaoman

具有宽视场（FOV）的无遮挡反射光学系统具有重要的应用价值。但是，像差会随着系统FOV的增加而增加，因此很难设计宽FOV系统。本文提出了一种有效的实现离轴三镜系统超宽视场的设计方法。该方法在设计过程中逐步扩展了系统视场，并根据图像质量和一些约束条件对表面光学自由形式多项式项进行了扩展，最终得到了预期的超宽视场系统。以一个焦距为1000mm，F值为10，超广角FOV为80°×4°的自由轴外三镜成像系统为例。

songshaoman

Design of off-axis three-mirror systems with ultrawide field of view based on an expansion process of surface freeform and field of view
QINGYU MENG,1,2,* HONGYUAN WANG,2 WENJING LIANG,3 ZHIQIANG YAN,2 AND BINGWEN WANG2

Unobscured reflective optical systems with a wide field of view (FOV) have significant application values.However, the aberration increases with the increase of the system FOV, so a wide FOV system is difficult to design. In this paper, a design method that is effective in achieving off-axis three-mirror systems with ultrawide FOV is proposed. In this method, the system FOV is expanded stepwise in the design process, and the surface optical freeform polynomial terms are extended based on the judgment of image quality and some constraint conditions, and to obtain a prospective ultrawide FOV system. A freeform off-axis three-mirror imaging system with a focal length of 1000 mm, an F-number of 10, and an ultrawide FOV of 80° × 4° is designed as an example.This design result shows that the system has a high imaging quality of RMS wavefront error value of 0.040λ
λ  0.633 μm, and it demonstrates that the method is effective in achieving off-axis three-mirror systems with an ultrawide FOV. © 2019 Optical Society of America