径向偏振光束经三角形点阵列板衍射的偏振奇点  

Polarization Singularities of Radially Polarized Beam Diffracted by a Triangular Multipoint Plate

作　　者：贺萌[1] 刘永欣[1,2] 蒲继雄[1] 

机构地区：[1]华侨大学信息科学与工程学院,福建厦门361021 [2]四川大学激光物理与化学研究所,四川成都610064

出　　处：《中国激光》2012年第B06期47-53,共7页Chinese Journal of Lasers

基　　金：基金项目：国家自然科学基金（60977068,61178015）资助课题.

摘　　要：根据夫琅禾费衍射积分公式推导出径向偏振光束通过三角形点阵列板（TMP）衍射后的传输表达式，通过理论计算模拟并进行实验验证，得到衍射场光强分布图，衍射场光强成周期性排列。并用复Stokes场来分析径向偏振光束衍射场偏振奇点的变化规律。结果表明，衍射场的光强分布随着三角形点阵列板N值的改变而改变，偏振奇点的数目随着三角形点阵列板的N值的增大而增多。另外，光束参数（波长和光束束宽）、传输距离和三角形点阵列板的参数（三角板边长）均对偏振奇点的位置产生影响。改变三角形点阵列板的N值，伴随有偏振奇点的产生和湮灭现象。Based on the Fraunhofer diffraction integral formula, the propagation expressions for radially polarized beam diffracted by a triangular multipoint plate （TMP） are derived. Through the theoretical calculation and experiments, the intensity distribution in the diffraction field arranged periodically is got. The polarization singularities of radially polarized beam in the diffraction field by using the complex Stokes fields is analyzed. It is shown that the light intensity patterns varies with the N-value of the TMP. The number of the polarization singularities increases with the N-value of the TMP. The beam parameters （the wavelength and the waist width of the beam）, transmission distance and the parameters of the TMP （the size of each side of the triangle） have influences on the positions of the polarization singularities. The creation and annihilation of the polarization singularities may appear as the N-value of the TMP varies.

关 键 词：激光光学 光强分布 偏振奇点 径向偏振光 三角形点阵列板 

分 类 号：O436[机械工程—光学工程]