基于调制光束的空间相干性获得局域空心光束

Generation of bottle beam by modulating spatial coherence of light beam

通过调制部分相干光的空间相干性,实现了局域空心光束的产生。理论上根据范西泰特-策尼克定理及标量衍射积分,构造出具有一定空间相干性的部分相干光,并研究其聚焦特性。实验上采用理论上要求的光学系统来构造具有特定空间相干性的部分相干光,并采用薄透镜聚焦部分相干光。研究表明,当构造出的部分相干光经透镜聚焦,可得到局域空心光束。研究了光学系统的参数及透镜焦距对产生局域空心光束的影响,结果显示:光阑的拦截比及透镜的焦距越大,获得的空心光束的尺寸就越大。

Generation of bottle beam by modulating the spatial coherent coefficient of partially coherent beams is investigated. Based on the theorem of van Cittert-Zernike and scalar diffractive theory, partially coherent beam with particular coherent coefficient is constructed. And focused properties of this kind of partially coherent beam is studied. Based on theoretical results, an optical system to achieve the special partially coherent beams, and focus partially coherent beams with a thin lens is designed. The results indicate that particular partially coherent beams can be converted into bottle beam after focusing by thin lens. Moreover, the influence of parameters of optical system and focus length of thin lens on construction of the bottle beam is studied. The greater of lens focal length and interception ratio, the larger size of the bottle beam.