棱镜色散成像光谱仪的谱线漂移特性

Spectral Line Shift Property of Prism Dispersive Imaging Spectrometer

为了研究棱镜色散成像光谱仪的谱线漂移特性,介绍了成像光谱仪谱线漂移的影响因素及机理,基于线性光学模型建立了描述谱线漂移特性的数学模型。在Matlab环境下利用Code V的API函数对系统进行了光线追迹,验证了数学模型的正确性,分析了谱线漂移的灵敏度系数。结果表明:工作环境变化引起的镜面刚体位移是导致成像光谱仪谱线漂移的主要原因;在偏心不大于0.2mm、倾斜不大于0.02°的小量级干扰下,不同波长、不同视场位置的谱线漂移量相等,误差小于0.1个像元;镜面刚体位移对谱线的影响是线性的、相互独立的,谱线漂移量是各刚体位移引起谱线漂移量的代数和。基于线性光学模型建立的谱线漂移模型可用于描述成像光谱仪的谱线漂移特性,对光谱定标、复杂工况下的光谱特性分析和预测具有指导意义。

In order to study the spectral line shift property of prism-dispersive imaging spectrometer,the influencing factors andmechanisms of spectral line shift were presented,and the mathematical model based on linear optics model was established to de-scribe the spectral line shift property.Code V API functions was used,in Matlab environment,to verify the validity of mathe-matical model,and the sensitivity coefficient of spectral line shift was analyzed.Results indicate that rigid body motion of opticalmirror surface generated by environmental variation is the key causation of spectral line shift.When the decenter of mirror sur-face is no more than 0.2mm and the tilt is less than 0.02°,the value of spectral line shift of different wavelengths at differentfields is equivalent,and the error is less than 0.1pixel.Spectral line shift due to mirror rigid body motion is linear and independ-ent,and the total shift of the spectral line is the algebraic sum of values produced by the single freedom of motion（DOF）of sin-gle mirror surface.The mathematical model based on linear optics model can be used to study the spectral line shift property ofthe prism-dispersive imaging spectrometer.It will provide some guidance for spectral calibration and spectral property analysisunder complex work condition.