摘要
通过对不同拓扑荷的涡旋光束经随机表面散射后在衍射区形成的横向和纵向光强分布的模拟,发现散斑颗粒的横向和纵向的平均尺寸比用高斯光束照明随机表面产生的散斑颗粒平均尺寸小很多,并且随着涡旋光束拓扑荷和光斑半径的增大而减小,同时散斑场相位涡旋的密度随着涡旋光束拓扑荷和光斑半径的增大而增大。利用这种方法可以方便地选择不同拓扑荷和光斑半径的涡旋光束照射随机表面,得到合适的散斑颗粒来捕获更小的微粒。这种结果还可以用来降低散斑噪声。
The transversal and longitudinal intensity and phase distribution of speckle fields in diffraction patterns of random scattering surfaces under vortex beam with different topological charges are simulated. It is observed that the transverse and longitudinal average size of speckle grains is smaller than that of speckle grains produced by Gauss beam passing through the random scattering surfaces, and it becomes smaller with the increase of the topological charge and radius of vortex beam. At the same time, the density of phase vortices becomes larger with the increase of the topological charges and radius of vortex beam in the diffraction region. The speckle sizes can be adjusted by changing the topological charges and radius of vortex beam to trap particle. This result can be used to reduce the noise.
出处
《光学学报》
EI
CAS
CSCD
北大核心
2014年第11期294-300,共7页
Acta Optica Sinica
基金
国家自然科学基金(10974122)
关键词
物理光学
成像系统
衍射
physical optics
imaging systems
diffraction
