一种空心光束的简易实现方法

A Simple Way for Generating Hollow Beams

利用玻璃毛细管作为空心波导,研究聚焦光束在其中的传输特性.实验结果表明:当聚焦光束以正射方式入射到空心玻璃毛细管波导时,经玻璃毛细管传输后的聚焦光束由原先的高斯光束变成零阶贝塞耳光束;而当聚焦光束非正射入射时,即聚焦光束以其光轴与毛细管中心细孔的中心轴成某一角度入射时,经传输后的聚焦光束由原先的高斯光强分布变为空心光强分布.此外,不同长度的毛细管及不同的入射角,都会对所产生的空心光束的黑斑尺寸和发散角产生影响.

Using a glass capillary as hollow waveguide, the propagation property of the focused beam passing through it was studied. By the experimental investigation, we find that when the optical axial of the focused beam is parallel to the glass capillary, the intensity distribution of the focused beam is change from Gauss type to zeroth-order Bessel type. However, if the optical axial is not parallel to the glass capillary, namely a angle between optical axial of focused beam and glass capillary exist the focused beam change into a hollow beam. Moreover we experimentally investigate the influ- ence the length of the glass capillary and the angle between optical axial of focused beam and glass capillary on the parameters of the generated hollow beam, including the size and the divergence of the hollow beam.