提出一种产生局域空心光束(bottle beam)的新方法,它是在传统的轴棱锥底面上放置一个环形障碍物.平面波入射到带有环形障碍物的轴棱锥底面时,将在轴棱锥产生的最大无衍射距离内形成bottle beam,而在bottle beam的前后仍然保持无衍射贝塞尔光.通过变化障碍物大小及轴棱锥底角实现bottle beam尺寸的控制.利用衍射理论描述了平面波经带有环形障碍物的轴棱锥产生bottle beam的原理,分析和模拟了传输过程中不同位置的截面光强分布及整个过程的三维光强分布,并给出相关的实验结果.研究结果对bottlebeam的实际应用具有积极的意义.
A new method of generating bottle beam was proposed for the first time,which is compriecs a traditional axicon with a ring obstacle at its underside. When a plane wave illuminates the bottom of axicon with ring obstacle,a bottle beam is generated within the maximum non-diffractional distance,and the beam keeps as non-diffractional Bessel beam in front and behind the bottle beam. Controlling the size of bottle beam is realized by changing the size of obstacle or cone angle of axicon. The principle of generating bottle beam when a plane wave illuminates the ring obstacle-axicon was described using the diffraction theory. The transverse intensity distribution of the bottle beam in propagation and the three-dimensional intensity distribution of the whole process were analyzed and simulated,and the experiment results were presented. The result shows significant guidance value for the practical application of the bottle beam.