锥台和轴棱锥系统产生的尺寸可调局域空心光束

Bottle beam with adjustable size generated by a frustum and axicon system

为了解决现有光学系统产生局域空心光束尺寸不易调整的问题,提出了一种由不同底角的锥台和正轴棱锥组合而成的新型光学系统。采用衍射积分和汉克尔波理论对该系统的光束变换特性进行了分析,可知平面波通过新型光学系统后将产生局域空心光束,且通过改变两个光学元件之间的相对位置可以调节局域空心光束的尺寸。在此基础上结合几何光学理论给出局域空心光束相关参量的计算公式;并采用光学分析软件TRACEPRO模拟了新型光学系统中局域空心光束不同位置处的光强分布及其随锥台与正轴棱锥之间距离的变化。结果表明,软件模拟的结果与理论分析的结果基本一致,新型光学系统能够产生尺寸可调的局域空心光束。

In order to adjust the size of bottle beam which was not adjustable flexibly in a current optical system, a novel optical system composed of one frustum and one axicon with different conical angle was proposed. The beam transformation property of this new system was analyzed by diffraction integral and Hankel wave theory. When a plane wave passes through the novel optical system, a bottle beam is formed and the size of bottle beam can be adjusted by changing the relative position between both the optical elements. Based on the analysis, the relevant parameters of bottle beam were also calculated by geometrical optics. The intensity distribution of bottle beam in different positions after the novel optical system was simulated by TRACEPRO software and the intensity distribution with the change of the relative position between frustum and axicon was also analyzed. The result of simulation is consistent with the result of theoretical analysis. The conclusion shows that bottle beam with adjustable size can be generated by the novel optical system.