基于斯托克斯偏振探测的植物叶片偏振特性研究

Polarization Characteristics Analysis of Plant Leaves Based on Stokes Polarization Detection

由于植物叶片属于强散射介质,为了准确描述叶片的散射特性,采用自行搭建的斯托克斯偏振成像系统,对植物叶片斯托克斯矢量进行计算,使用偏振均匀度这一物理量对其偏振特性进行了系统的研究:1)探究了圆偏振光与线偏振光在植物叶片上的偏振特性,发现以线偏振光为入射光时,叶片的偏振均匀度较大;2)研究了植物叶片叶脉方向与偏振光方向之间的依赖关系,发现当线偏振光方向与叶片叶脉方向垂直时,叶脉的偏振均匀度最大;3)得到了退偏参数与叶片含水率之间的关系,发现随着叶片含水率逐渐降低,叶片的偏振均匀度逐渐增大。通过自行搭建的偏振探测系统探测偏振光与植物叶片之间的相互作用,发现了叶片的偏振均匀度可以较好地描述其对偏振光的退偏特性,为后续对植物的微观结构、生长状态检测等研究打下了基础。

Given that plant leaves correspond to strong scattering media,a selfbuilt Stokes polarization imaging system is used in this study to accurately describe the scattering characteristics of leaves.By further calculation of Stokes vector of plant leaves,the polarization uniformity of the physical quantity is used to systematically examine their polarization characteristics:1)the polarization characteristics of circularly polarized light and linearly polarized light on plant leaves are investigated,and it is determined that the polarization uniformity of leaves is higher under the incidence of linearly polarized light when compared to circularly polarized light;2)the dependence between the angle of leaf vein and direction of polarized light is examined,and it is determined that when the direction of linear polarized light is perpendicular to the angle direction of leaf vein,the polarization uniformity of leaf vein is the highest;3)the relationship between depolarization parameters and leaf water content is obtained.It is observed that as the leaf water content gradually decreases,the polarization uniformity of the leaf correspondingly increases.By examining the interaction between polarized light and plant leaves,this study demonstrates that polarization uniformity is a significant descriptor of leaf depolarization characteristics in response to polarized light.This insight lays a foundation for subsequent research into plant microstructure and growth state.