光栅色散型成像光谱仪室内外光谱定标中心波长偏移研究

摘要

成像光谱仪使用前需要对其进行光谱定标以确定其各光谱通道的中心波长和光谱带宽.但是室内外光谱定标实验结果表明随着使用环境的变化成像光谱仪各通道的中心波长和带宽将发生变化.对光栅色散型成像光谱仪各光谱通道的中心波长室内外定标结果的偏移进行研究,从光栅色散型成像光谱仪的光学结构和工作环境参数出发对造成其中心波长偏移的因素进行分析和建模,对震动、机械形变和浓度等主要影响因素进行理论推导和数量级估算,结合实验结果进行对比分析.理论推导和实验数据分析都表明光栅色散型成像光谱仪室内外光谱定标获得的各通道中心波长的偏移量与各通道的本征波长成二次函数的关系,其中震动和机械形变所带来的系统光路结构的细微改变是造成其中心波长偏移的主要因素,使用环境温度的差异也对该成像光谱仪各光谱通道的中心波长具有一定的影响.%Spectral calibration must be carried out in order to determine its central wavelength and half-wave band width of each pixel before the usage of imaging spectrometer.But it was found out that these parameters vary as environment changes.The present paper studies the effect based on test field data.The authors analyzed the optical structure and compared the working environmental parameters.Then a theoretical model is established and the influences of vibration,distortion and temperature parameters are evaluated.The theoretical model and the caculation results are in good consistency,which testifies the theoretical model.This research will shed some light on the high accuracy spectral calibration of the grating based imaging spectrometer and its manufacture.