双轴锥镜光束变换分析

Analysis Of Beam Transformation of Biaxial Conical Mirror

基于轴锥镜和瑞利-索末菲矢量衍射理论,对无衍射光的产生及产生后的光场进行详细的理论分析。采用数值模拟对两束无衍射光的空间光场分布和轴上光强分布曲线进行仿真,基于锥镜加工工艺,对锥镜的锥角和第一、第二轴锥镜出射后的光束进行光场分析。结果表明:当第一轴锥镜的锥角小于第二轴锥镜时,出射光束在干涉重合区的光强为两部分光场的耦合叠加,并产生新的无衍射光束;反之,出射后的两束无衍射光不重合,继续保持各自的无衍射特性。其次,出射光束沿垂直于传输方向上的横截面上呈同心圆环分布,且同心圆环的半径随传输距离的改变而改变。从理论和模拟上均实现了两束无衍射光束的强度分布、光束分布及圆环环径的可调,这对无衍射光束应用于大尺度空间精密测量、粒子微操纵等领域具有重要的指导意义。

Based on the axial cone mirror and the Rayleigh-Sommerfeld vector diffraction theory,a detailed theoretical analysis of the generation of non-diffracted light and the light field after the generation is carried out.The spatial light field distribution and the on-axis light intensity distribution curve of the two non-diffracted beams are simulated by numerical simulation,and based on the processing technology of the conical mirror,the light field analysis of the conical angle of the conical mirror and the beam emitted from the first and second axis conical mirrors are carried out.The results show that when the conical angle of the first-axis conical mirror is smaller than that of the second-axis conical mirror,the light intensity of the outgoing beam in the interference coincidence region is a coupled superposition of the two parts of the light field,and a new non-diffracted beam is generated;conversely,the two diffraction-free beams do not coincide and continue to maintain their respective non-diffracted characteristics.Second,the outgoing beams are distributed in concentric rings along a cross-section perpendicular to the transmission direction,and the radius of the concentric rings varies with the transmission distance.In this paper,the intensity distribution,beam distribution and ring diameter of the two nondiffracted beams are tuned both theoretically and numerically,which is an important guideline for the application of nondiffracting beams in large scale space precision measurements and particle micromanipulation.