圆顶轴棱锥底角及焦距对局域空心光束的影响

Influence of base angle and focal length of vaulted axicons on bottle beams

从衍射理论导出圆顶轴棱锥后的光场分布,用软件对圆顶轴棱锥后的光强进行仿真,结果表明,圆顶轴棱锥可以得到多个局域空心光束。分别改变圆顶轴棱锥的底角和顶端平凸透镜的焦距,再用软件对圆顶轴棱锥后的光强进行仿真,所得光强分布表明,圆顶轴棱锥的底角影响局域空心光束的周期和暗域数量,而顶端平凸透镜的焦距主要影响局域空心光束中暗域的数量,对周期几乎没有影响。在实际应用中可通过调节参量得到所需要局域空心光束。

The distribution of light field behind a vaulted axicon is calculated with diffraction theory and simulated with soft ware, the resuh demonstrates that vaulted axicons can he used to generate bottle beams. The light intensity is simulated again af ter changing the base angle or the focal length, the result shows that the base angle of vaulted axicons has some effect on the peri od and the number of dark regions of bottle beams, while the focal length of piano-convex lenses on the top of vaulted axicons is related to the number of dark regions but has little effect on the period. The required bottle beam can be obtained according to ad- justing the relevance parameters in practical application.