临边成像光谱仪光谱辐亮度响应度定标研究

Spectral radiance responsivities calibration of limb imaging spectrometer

基于积分球原理,提出了一种利用积分球进行光谱辐亮度响应度定标的新方法,消除了利用积分球定标的传统方法中由于漫反射板的双向反射率分布函数(BRDF)的测量不确定度大对定标精度的影响,极大地提高了定标精度。利用该方法标定了在研的空间遥感临边成像光谱仪原型样机的光谱辐亮度响应度,分析了定标不确定度,定标合成不确定度为2.6%。将该方法的定标结果与采用标准灯联合漫反射板的定标结果进行了分析比对,结果表明,二者在3%以内相符。引起两种定标结果偏差的主要原因是漫反射板BRDF测量的不确定度。

A new method for calibrating the spectral radiance responsivities based on integrating sphere principle is proposed.The effect of the uncertainties in measurements of bidirectional reflectance distribution function（BRDF） of the diffuser is eliminated and the calibration precision is evidently improved.Using this new method,the spectral radiance responsivities of the space-borne remote sensing limb imaging spectrometer is calibrated.The uncertainties of the calibration is analyzed,and the combined uncertainties is 2.6%.A comparison between the directly standard lamp and this method is performed.A conclusion is drawn that the spectral radiance responsivities using these two method are consistant within 3%.The discrepancy of the two methods results from the uncertainties in the measurements of（BRDF） of the diffuser.