摘要
针对基于传统光学元件的成像光谱仪,在实现大视场与宽波段的同时难以满足结构紧凑的问题,在Offner成像光谱仪的第三反射镜引入圆锥曲面叠加条纹泽尼克多项式表征的自由曲面。基于矢量像差理论,分析了四阶以下的泽尼克多项式在系统中引入的像散与系统视场、波长的关系,通过选取合理的多项式叠加到圆锥曲面,设计了一款工作于可见光到短波红外波段(400~2500 nm)、体积仅42 mm×82 mm×100 mm的成像光谱仪。系统实现了双波段探测,来自两个不同宽度狭缝的光线经光栅分光后,通过分束器将工作波段分为可见近红外(400~1000 nm)和短波红外(1000~2500 nm),优化设计结果表明,光谱分辨率分别为2.8 nm和4 nm,成像质量良好,为实现宽波段紧凑型成像光谱仪的设计提供了理论参考。
Objective Imaging spectrometer can obtain spatial and spectral information of targets simultaneously,and it has been widely applied in ground object analysis,space remote sensing,target reconnaissance,and other aspects.As spectral imaging technology develops,designers hope that the imaging spectrometer can achieve a wider field of view(FOV)and wavelength band while meeting the structural compactness.In this aspect,the Offner imaging spectrometer shows excellent performance.However,with the expanding FOV and wavelength band,the aberration correction is more difficult.The Offner imaging spectrometer employing a traditional spherical mirror usually balances aberration by relaxing the size limits or adding lenses to the system,thereby leading to the increasing volume or complexity but failing to meet the requirements of lightweight and compactness.With the development of manufacturing and testing technology,the freeform surface has been widely employed in optical design.It is a kind of nonrotationally symmetric optical element,which can introduce more degrees of freedom into optical design.Introducing freeform surfaces into imaging spectrometers can improve the aberration correction ability of the system.However,too many freeform surfaces in optical systems or too many freeform terms on optical surfaces will cause a large deviation in the sag of surfaces,which will not only reduce the aberration correction ability of freeform surfaces in the system but also make the manufacturing of freeform surfaces more difficult.Therefore,we want to use a reasonable freeform surface in the imaging spectrometer design to achieve broad wavelength band and compact volume simultaneously.Methods The main aberration in the Offner imaging spectrometer is astigmatism.Firstly,the expression of the thirdorder astigmatism of the system is obtained based on the vector aberration theory.The analysis of the expression of thirdorder astigmatism shows that the astigmatism of the system increases with the increase of FOV and wavelength band.In the
作者
韩继周
赵世家
冯安伟
张幸运
季轶群
Han Jizhou;Zhao Shijia;Feng Anwei;Zhang Xingyun;Ji Yiqun(School of Optoelectronic Science and Engineering,Soochow University,Suzhou 215006,Jiangsu,China;Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province&Key Lab of Modern Optical Technologies of Education Ministry of China,Suzhou 215006,Jiangsu,China;Collaborarive Innovation Center of Suzhou Nano Science and Technology&Engineering Research Center of Digital Imaging and Display,Ministry of Education,Suzhou 215006,Jiangsu,China)
出处
《光学学报》
EI
CAS
CSCD
北大核心
2023年第14期212-220,共9页
Acta Optica Sinica
基金
国家自然科学基金(61405134,61340007)
国防基础科研计划(JCKY2018414C013)
江苏省自然科学基金(BK20161512)
江苏高校优势学科建设工程资助项目(PAPD)。
