光栅色散型成像光谱仪工作在可见近红外波段，主要用于海洋水色遥感。仪器采用推扫式成像，共设置15个光谱通道，穿轨方向由1024个像元组成，总视场宽度为14.2°。成像仪的各光谱通道对入射光的偏振状态敏感，为了提高大气顶入瞳辐射的测量精度，需要了解仪器的偏振响应特性，包括偏振灵敏度和相位角。发射前搭建了偏振测试系统，测量仪器的偏振灵敏度和相位角，它们是光谱通道和视场像元的函数。其中980 nm波段的偏振灵敏度最高，平均值约为4.69%，443 nm波段的偏振灵敏度最低，平均值约为1.81%。随着视场的变化，灵敏度呈现中间低，两边高的变化规律。提出成像仪偏振响应校正方法，利用偏振状态已知的入射光进行实验验证，结果表明该方法可将成像光谱仪偏振响应引入的辐射测量不确定度降低1%~6%。

The grating dispersive imaging spectrometer is used for ocean color remote sensing. It is operated in the visible and near infrared range. A push-broom method is applied to the instrument. 15 spectral channels and 1024 cross-track pixels comprising a total field of view of 14.2° are arranged on the focal plane. The spectral channels are sensitive to the polarization of the incident light. To improve the radiation measurement precision at the top of atmosphere, it is necessary to understand the polarization response characteristics of the instrument, including the polarization sensitivity and the phase angle. A polarization testing system is established before launching. The polarization sensitivity and the phase angle data of all spectral channels, which vary with the channel No. and the cross-track pixel, are measured. The 980 nm band has the highest polarization sensitivity and its mean of the cross-track pixels is about 4.69%, while the 443 nm band has the lowest sensitivity with a mean of about 1.81%. The sensitivity of middle field of view is lower than that at the edges in the same channel. A polarization response correction method is proposed for the imaging spectrometer. Verification experiments are performed by introducing the partially polarized light with a known polarization state. The result shows that the radiometric uncertainty caused by polarization response of the instrument can be reduced by 1%-6%.