为了对PGP成像光谱仪所获得的光谱数据进行定量化分析,需对PGP 成像光谱仪进行光谱定标,以获得各光谱通道的中心波长、光谱分辨率及成像光谱仪的光谱弯曲等光谱特性信息。采用单色准直光法设计了一套全视场自动化的光谱定标系统,系统中引入球面镜为待测的成像光谱仪光谱定标提供准直光,通过可自动控制的折转镜改变定标入射光线的入射角,以此实现待测成像光谱仪空间维不同视场的自动化光谱定标。运用该定标系统对PGP成像光谱仪进行光谱定标实验,得到该成像光谱仪的光谱性能参数,并结合定标系统的结构特点,对实验的结果进行了精度分析。实验分析结果表明该系统对PGP 成像光谱仪的中心波长定标精度达到0.1nm,光谱分辨率定标精度达到1.3%。该研究设计的全视场自动化光谱定标系统具有结构新颖紧凑、通用性较强、光谱定标精度较高等特点,且由于自动化的控制,避免了由于人为参与定标过程所带来的额外误差。该系统可用于实现PGP成像光谱仪及其他同类型成像光谱仪的光谱定标。
In order to analyze spectral data quantitatively which is obtained by prism-grating- prism imaging spectrometer,spec-tral calibration is required in order to determine spectral characteristics of PGP imaging spectrometer,such as the center wave-length of every spectral channel,spectral resolution and spectral bending.A spectral calibration system of full field based on col-limated monochromatic light method is designed.Spherical mirror is used to provide collimated light,and a freely sliding and ro-tating folding mirror is adopted to change the angle of incident light in order to realize full-field and automatic calibration of ima-ging spectrometer.Experiments of spectral calibration have been done for PGP imaging spectrometer to obtain parameters of spectral performance,and accuracy analysis combined with the structural features of the entire spectral calibration system have been done.Analysis results indicate that spectral calibration accuracy of the calibration system reaches 0. 1 nm,and the band-width accuracy reaches 1. 3%.The calibration system has merits of small size,better commonality,high precision and so on, and because of adopting the control of automation,the additional errors which are caused by human are avoided.The calibration system can be used for spectral calibration of other imaging spectrometers whose structures are similar to PGP.