基于量子遗传算法的自由曲面离轴反射光学系统设计

针对自由曲面离轴反射光学系统的初始结构较少、优化过程复杂的问题，提出了一种基于量子遗传算法的离轴反射光学系统设计方法，即采用量子遗传算法结合像差理论得到高像质的初始光学系统结构，再对其离轴化处理并引入自由曲面，进而设计得到自由曲面离轴反射光学系统。该方法可以方便、快捷地为自由曲面离轴反射光学系统提供像质良好、特定布局的初始结构。以离轴三反系统为例，采用该方法设计了一套工作在可见光波段、视场大小为10°×4°、F数为2的主三镜一体化的自由曲面离轴三反系统。仿真结果表明，该离轴三反系统视场较大、结构紧凑、成像质量良好，其最大RMS波像差为0.0485 λ (λ=0.6328 μm)，全视场的调制传递函数（MTF）在50 lp/mm处大于0.9，且一体化集成结构有利于简化系统的对准及装调。

Design of freeform surface off-axis reflective optical systems based on quantum genetic algorithm

Aiming at solving the problem of fewer initial structures and complicated optimization processes for freeform surface off-axis reflective optical systems, a method for designing off-axis reflective optical systems based on quantum genetic algorithm was proposed. In such method, quantum genetic algorithm combined with aberration theory was adopted to obtain an initial optical system structure with good image quality, and then the off-axis process was accomplished and the freeform surface was further introduced to obtain the well-designed freeform surface off-axis reflective optical system. The method could easily and quickly provide initial structure with good image quality. Taking the off-axis three-mirror system working in visible light band as an example, a freeform surface off-axis three-mirror system with field-of-view of 10°×4° and F-number of 2 was designed with the primary mirror and the tertiary mirror being integrated together. Simulation results indicate that the designed off-axis three-mirror system exhibits a large field-of-view, a compact structure and a good image quality. The maximum root mean square (RMS) wavefront error of the system is 0.0485 λ (λ=0.6328 μm) and the modulation transfer functions (MTF) of the full fields are all greater than 0.9 at 50 lp/mm. Besides, the integrated structure is benefit for the simplification of the alignment and installation of the system.