宽视场航空高光谱成像仪光学系统设计

Optical System Design of Airborne Wide Field-of-view Hyperspectral Imager

宽视场大相对孔径航空高光谱成像仪已成为航空海洋水色遥感等领域的迫切需求,根据宽视场和大相对孔径的研究目标,采用离轴两镜消像散望远镜和改进型Offner光谱仪匹配的结构型式,设计了一个视场40°、相对孔径1/2.2、工作波段0.4～1.0μm的航空高光谱成像仪光学系统,在传统Offner光谱仪中插入同心弯月透镜来提高Offner光谱仪的相对孔径和成像质量.运用光学设计软件ZEMAX对高光谱成像仪光学系统进行了光线追迹和优化设计,并对设计结构进行了分析.结果表明：光学系统各个波长的光学传递函数在奈奎斯特频率28lp/mm处均达到0.67以上,谱线弯曲和谱带弯曲均小于6.5%像元,便于光谱和辐射定标,完全满足设计指标要求,且体积小、重量轻,适合航空遥感应用.

Airborne ocean colour remote sensing urgently require wide angle and large relative-aperture hyperspectral imager.Based on the research objective of wide angle and large relative-aperture,an airborne hyperspectral imager optical system was designed using an off-axis two-mirror anastigmat telescope and a modified Offner spectrometer.The field of view of hyperspectral imager was 40°,relativeaperture was 1/2.2,and working waveband was from 0.4μm to 1μm.Relative aperture and image quality were improved by inserting a concentric meniscus in a classical Offner spectrometer.Ray tracing,optimization and analysis were performed by ZEMAX software.The analyzed results demonstrate that the MTF for different wavelengths is more than 0.67 at Nyquist spatial frequency 28lp/mm,both smile and keystone are less than 6.5% of the size of pixel.It is easy for spectral and radiation calibration.The design results satisfy the requirements of specifications,the volume is small,mass is low,and is suitable for airborne remote sensing.