光涡旋偶极子经1/4屏衍射后的演化

Evolution of an Optical Vortex Dipole Diffracted by a Quarter Screen

根据菲涅尔衍射积分,导出了存在于高斯光束中的光涡旋偶极子经过1/4屏衍射后的演化公式,分析了光涡旋偶极子经过1/4屏衍射后的演化特点.研究表明,通过1/4屏衍射后,衍射场中出现多对光涡旋偶极子,随着衍射距离的增加,最终在衍射场中只产生一个涡旋.随离轴量参数的变化,光涡旋偶极子出现渐变形式的演化特性.

The equations of optical vortex dipole diffracted by a quarter screen which exist in Gauss beam are derived according to the Fresnel diffraction integral,and a detailed analysis of evolution characteristics about the op- tical vortex dipole by a quarter screen are made. The result shows that,by the quarter screen diffraction,multiple pairs of optical vortex dipoles occur in the diffraction field. Meanwhile, with the change of off-axis parameter, the evolution characteristic of the optical vortex dipoles are changed gradually.