基于谐衍射的宽波段大口径衍射光学系统设计

Designing a Broadband Large Aperture Diffractive Optical System Basedon Harmonic Diffraction

为实现大口径衍射光学系统宽波段成像,分析了传统衍射透镜基于Schupmann结构光路模型带宽增加带来的中继镜口径变大的问题,提出采用谐衍射透镜作为主镜构建大口径宽波段衍射光学系统,设计了口径为10 m谱段覆盖400~900 nm的大口径光学系统,中继镜的口径与传统设计相比减小了2.4 m。为验证该设计方法,设计一套口径为80 mm、光谱范围为400~900 nm的成像光学系统,并对该系统进行了成像实验,通过查看鉴别率靶图像无色差,验证了基于谐衍射透镜为主镜的宽波段成像设计方法,为大口径衍射光学系统设计提供了一种思路。

To realize the broadband imaging of large aperture diffractive optical systems,we analyze the problem of increasing relay lens diameter due to the increased bandwidth of traditional diffractive lenses based on the Schupmann structure optical path model.We propose using a harmonic diffractive lens as the primary mirror to construct a large aperture broadband diffractive optical system.A large aperture optical system with an aperture of 10 m and a spectrum covering 400‒900 nm is designed,and the aperture of the relay lens is reduced by 2.4 m compared with the traditional design.To verify the design method,an imaging optical system with an aperture of 80 mm and a spectrum of 400‒900 nm is designed,and imaging experiments are carried out on the system.By checking the resolution target image with no chromatic aberration,the broadband imaging design method based on a harmonic diffractive lens as the primary mirror is verified,which provides an idea for designing a large aperture diffractive optical system.