分析了星载成像光谱仪杂散光的来源和危害,研究了杂散光对此类光谱仪光谱测量精度的影响.介绍了用点扩散函数描述成像光谱仪杂散光的原理,推导了杂散光影响矩阵和杂散光修正矩阵的求解,给出了杂散光测量和修正的具体方案,并对测量和修正精度进行了分析.实验表明,基于点扩散函数的矩阵法可实现成像光谱仪杂散光的测量和修正.像元中心波长入射时,修正后有效信号降低不足1%,杂散光信号降低至少99%;像元中心波长和非像元中心波长同时入射时,修正后像元中心波长处有效信号降低7%左右,非像元中心波长处有效信号降低25%左右,杂散光信号降低近50%.最后,从原理上解释了杂散光修正效果受入射光波长影响的原因.%To reduce the influence of stray lights on the spectral measurement accuracy of a High Resolution Imaging Spectrometer(HRIS), sources and hazards of stray lights were analyzed. Based on the Point Spread Function (PSF) theory which is usually used to describe the stray lights of HRISs,the influence matrix and the correction matrix of stray lights were discussed. The measurements and specific correction programs were given, and the accuracies of measurement and correction were analysed. The results show that the method based on PSF can complete the measurement and correction of stray lights for the HRIS. For a pixel center wavelength incident light, the effective signal is only reduced no more than 1％, while the stray light signal is reduced at least by 99 ％ as compared with the raw data. For both pixel center wavelength and non-pixel center wavelength incident lights, the corrected signals are reduced by about 7％ at the pixel center wavelength and by nearly 25％ at the non-pixel center wavelength, while the stray light signal is reduced by almost 50 ％. Finally, the theoretical reasons why the incident light wavelength affected the stray light correction were explained.
展开▼
