周期局域空心光束自重建的理论模拟与实验

Theoretical Modulation and Experiment on the Self-Reconstruction of Periodic Bottle Beam

利用衍射积分理论和干涉理论分析了轴棱锥对无衍射贝塞尔(Bessel)光束进行线聚焦产生局域空心光束遇障碍发生自重建的全过程。数值模拟了周期局域空心光束的传输情况及轴上放入圆形障碍物后不同位置的截面光强分布图,并计算了障碍物后最小自重建距离。研究结果表明周期局域空心光束遇到障碍物后,会绕过障碍物继续向前传输,并且传输一段距离后恢复原来的周期局域空心光束的特性。设计实验光路图对理论模拟进行了验证,通过显微镜和照相机系统拍摄得到轴上圆形障碍物和方形障碍物前后光束的截面光强分布图,实验与理论模拟相吻合。研究结果使得周期局域空心光束的应用得到了扩展。

The theories of diffraction integral and interference are used to analyze the whole process of self- reconstruction of periodic bottle beam which is generated by line-focusing the non-diffracting Bessel beam through an axicon. The intensity distributions along the propagation distance of the periodic bottle beam and the cross-section intensity distribution in different distance after the circle obstacle is simulated numerically~ the minimum distance of self-reconstruction is calculated. The results of the proposed work show that after encountering obstacles, the periodic boitle beam will transport around obstructions, transmit along and restore the original characteristics after a distance transmission cycle bottle beam. Optical system is designed to prove the theoretical simulation, the cross- section intensity distribution around a circle or quadrate obstacle can be observed by a microscope and camera system and the experimental results agree well with the theoretical analysis. The results expand the application of the periodic bottle beam.