风云二号扫描辐射计可见杂散光的像元间差别

Difference among Pixels of FY-2 VISSR Visible Stray Light

对风云二号扫描辐射计中与直射杂散光相关的边框进行球坐标和极坐标的变换,得出了可见光通道的杂散光定量化模板,并采用链表方式进行存储。通过理论计算和分析,确定了杂散光在不同像元间的分布趋势,对辐射计折镜的所有工作角度和各个像元的杂散光总量进行了定量的计算和统计。结论对探测器的布局调整、光机设计改进和图像处理方法消除杂散光提供了可靠的依据。

With the coordinates of framework which related to the straight stray light transformed from spherical coordinate to polar coordinate, the quantitative templates of visible channel stray light of FY-2 VISSR has been established, then to be saved in linked list. The distribution tendency of stray light among pixels has been deduced by theoretical calculation and analysis, and then the quantitative calculation and statistical comparison of stray light among pixels with different working status of folded mirror have been carried out. Those results will provide reliable foundation to adjust the sensor arrangement, and to improve the optical and mechanical design and to suppress stray light by digital image processing.