大气遥感远紫外光谱仪绝对光谱辐照度响应度定标方法研究

Study on the Absolute Spectral Irradiation Calibration Method for Far Ultraviolet Spectrometer in Remote Sensing

主要针对可应用于空间高层大气遥感的远紫外光谱仪的光谱辐照度响应度定标方法进行研究。针对远紫外波段光谱测试标准装置少,实验系统所需真空度高,实验稳定性难以维持,传统漫反射板和积分球辐亮度定标方法在远紫外波段局限性大、难以利用等特点,研究了适用于远紫外光谱仪器的光谱辐照度绝对辐射定标方法,搭建了相应的真空实验系统,以一台远紫外光谱仪原理样机为对象对研究方法进行了实验验证。实验系统以标准氘灯、真空紫外单色仪和准直系统组成照射系统,将出射准直光辐照度用标准探测器进行标定,三者共同组成了标准光谱辐照度光源;利用该光源照射原理样机并读出相应信号,最终获得光谱辐照度响应度,从而实现了利用标准探测器进行照度传递的远紫外光谱仪器绝对光谱辐射定标,有效的进行了仪器定标。该方法定标不确定度约为7.7%,对远紫外波段空间高层大气遥感光谱仪的地面辐射定标研究具有重要意义。

The present paper studied spectral irradiation responsivities calibration method which can be applied to the far ultraviolet spectrometer for upper atmosphere remote sensing.It is difficult to realize the calibration for far ultraviolet spectrometer for many reasons.Standard instruments for far ultraviolet waveband calibration are few,the degree of the vacuum experiment system is required to be high,the stabilities of the experiment are hardly maintained,and the limitation of the far ultraviolet waveband makes traditional diffuser and the integrating sphere radiance calibration method difficult to be used.To solve these problems,a new absolute spectral irradiance calibration method was studied,which can be applied to the far ultraviolet calibration.We build a corresponding special vacuum experiment system to verify the calibration method.The light source system consists of a calibrated deuterium lamp,a vacuum ultraviolet monochromater and a collimating system.We used the calibrated detector to obtain the irradiance responsivities of it.The three instruments compose the calibration irradiance source.We used the ＂calibration irradiance source＂ to illuminate the spectrometer prototype and obtained the spectral irradiance responsivities.It realized the absolute spectral irradiance calibration for the far ultraviolet spectrometer utilizing the calibrated detector.The absolute uncertainty of the calibration is 7.7%.The method is significant for the ground irradiation calibration of the far ultraviolet spectrometer in upper atmosphere remote sensing.