偏振遥感是遥感领域的一个新兴对地观测手段, 地物反射的偏振效应是偏振遥感进行观测的基础。 然而, 地物反射具有偏振效应, 大气粒子的反射与散射也具有偏振效应, 并且大气的偏振效应往往大大强于地物偏振效应。 当用偏振遥感器对地表目标进行观测时, 大气的强偏振效应会干扰甚至覆盖地物的偏振信息。 因此, 如何最大限度地消除大气的偏振效应对地物偏振效应的影响是偏振遥感的一个关键性问题。 大气中性点是大气中偏振度趋近为零的区域。 利用大气中性点进行地-气分离理论的核心思想是将探测器放置于中性点区域进行对地观测, 以减弱大气偏振对地物偏振的影响。 基于国内首次大气中性点偏振遥感航空飞行实验, 通过处理和分析实验所得影像数据, 分别得到了中性点位置和非中性点位置影像偏振度分布, 发现中性点位置偏振度集中分布区域要明显小于非中性点位置, 验证了利用大气中性点进行地-气分离理论的合理性和可行性, 提出了利用中性点进行偏振遥感实验所需要的条件, 并初步分析出, 波长较长的波段更适合于偏振遥感观测。

Based on the objects polarization effects, polarization is a newly emerging method in the field of remote sensing. Both objects and atmosphere have polarization effects, however, the atmospheres polarization effects are much stronger than that of objects. Consequently, atmosphere polarization effects will interfere or even cover objects when observing with sensors. How to maximally eliminate the polarized effects generated by the atmosphere is a crucial problem in polarization remote sensing. Atmospheric neutral point is an area where the degree of atmosphere polarization is near to zero; therefore, if sensors are set up in this area, atmosphere polarization would be greatly eliminated, which is the main content of separating the effects between objects and atmosphere by its neutral point method. In this paper, after processing and analyzing the experimental data got from the first polarization remote sensing flight experiment with atmosphere neutral point, the degree of polarization images captured in neutral and non-neutral point area were obtained, and it can be seen that the main value of polarized degree of images got in neutral point area was obviously smaller than that in non-neutral point area. The results showed that the theory mentioned above was logical and practical. An innovation in our study is that the requirements needed in polarization remote sensing flight with neutral point were clarified. In the meantime, a qualitative conclusion was drawn that observing with longer wavelength is more applicable to polarization remote sensing.