部分相干焦散光束的形成及其相干特性  

Generation of Partially Coherent Caustic Beam and Its Spatial Correlation Properties

作　　者：杨艳飞 吴逢铁 胡汉青 胡润 朱清智 YANG Yan-fei;WU Feng-tie;HU Han-qing;HU Run;ZHU Qing-zhi(Fujian Key Laboratory of Light Propagation and Transformation, College of Information Science and Engineering, Huaqiao University, Xiamen , Fujian 361021, China)

机构地区：[1]华侨大学信息科学与工程学院福建省光传输与变换重点实验室,福建厦门361021

出　　处：《光子学报》2018年第7期169-176,共8页Acta Photonica Sinica

基　　金：国家自然科学基金(No.11774103);国家自然科学青年基金(No.61605049);福建省科技重大项目(No.2016H6016)资助~~

摘　　要：提出利用交叉谱密度函数描述焦散光束,将焦散光束的研究范围从相干光拓展到部分相干光领域.结合菲涅耳-基尔霍夫衍射积分公式,导出焦散光束在自由空间中的传输表达式.理论分析了光束射入不同倾斜角度轴棱锥引起的像散对焦散光束的影响,并设计相关实验进行了验证,实验结果与数值模拟相吻合.进一步研究入射光场相干性对焦散光束的影响,发现随着入射光场空间相干长度的降低,焦散光强的明暗分布会慢慢变模糊,光束中心的光点阵列逐渐消失.A new method is introduced by using the cross-spectral density function to describe the caustics beam,which is extended from fully coherent cases to the field of partially coherent cases for the first time.And the propagation formula of caustics beam is derived in the free space combined with the Fresnel Kirchhoff diffraction integral theroy.The influence of astigmatism introduced by tilted axicon at various inclination angles on partially coherent caustic beam with respect to the propagation axis was studied theoretically and experimentally.Furthermore,the partially coherent caustics beam is invested that is effected by the field coherence on the partially coherent caustic beam.Results show that the intensity contrast ratio between light focus and the surrounding dark regions can be reduced with the decrease of the spatial coherent lengths.

关 键 词：部分相干 交叉谱密度 焦散光束 轴棱锥 空间相干长度 

分 类 号：O439[机械工程—光学工程]