双折射器件对机载激光雷达偏振探测影响的研究

根据膜层理论给出了机载激光雷达回波信号垂直入射偏振棱镜时偏振平行分量透过率的数学解析表达式，定量分析了偏振棱镜对机载激光雷达回波信号平行分量透过率的影响，理论计算表明：棱镜晶体厚度、空气膜层厚度及棱镜结构角共同影响回波信号通过偏振棱镜的透过率；当回波信号波长为532 nm，利用1/2石英波片测得的偏振平行通道和偏振垂直通道的增益比k为1.2时，机载激光雷达偏振通道增益比k的真实值在1.003～1.463之间，若不考虑1/2波片对k值的影响，会给退偏振比反演带来较大的系统误差.

Impact of Birefringence Device on the Polarization Sounding of Airborne Lidar

Based on the theory of membranous layer,a mathematics analytical expression of polarization parallel components was proposed when backward echoed signals of airborne lidar incidence vertically on the crystal plane.The impact of polarizing prism on the polarization parallel components transmission of airborne lidar was analyzed quantificationally.Calculating results indicate that backward echoed signal polarization parallel component transmission of prism is affected by prism crystal thickness,air film thickness and angles of prism configuration.The real values of k of polarization sounding channels range from 0.82 to1.196 when measured value of k is 1.2 using 1/2 quartz retardation sheet under the condition of 532 nm wavelength backward echoed signal; however,the inversion of depolarization ratio will subject to bigger systematic error if the impact of 1/2 quartz retardation sheet on k is ignored.