圆平顶高斯光束经圆形光阑衍射的远场特性  

Far-field properties of circular flattened Gaussian beams diffracted by a circular aperture

作　　者：徐一清[1] 周国泉[1] 

机构地区：[1]浙江农林大学理学院,浙江临安311300

出　　处：《浙江大学学报（理学版）》2012年第5期541-546,共6页Journal of Zhejiang University（Science Edition）

基　　金：国家自然科学基金资助项目(No.10974179);浙江省自然科学基金资助项目(No.Y1090073)

摘　　要：基于角谱表述和稳相法,导出了圆平顶高斯光束经圆形光阑衍射后在远场的解析表达式,进而利用该公式数值计算了衍射圆平顶高斯光束在远场的归一化强度分布和远场发散角.结果表明,f参数对衍射圆平顶高斯光束远场傍轴性的影响相对较大,而截取参数δ的影响相对较小.衍射圆平顶高斯光束采用非傍轴处理和傍轴处理两者的差异与光束阶数N无关.随着f参数的增大,衍射圆平顶高斯光束的远场发散角先增大后趋向于一饱和值.增大截取参数δ,远场发散角先增大后趋向于一最小值.衍射圆平顶高斯光束的远场发散角几乎与光束阶数N无关.Based on the angular spectrum representation and the method of stationary phase,an analytically expression of the far-field of a circular flattened Gaussian beam(CFGB) diffracted by a circular aperture is derived.The normalized intensity distributions and the far-field divergence angles of diffracted CFGBs are numerically demonstrated in the far-field.The influence of the f-parameter on the non-paraxiality of the far-field of a diffracted CFGB is larger,and the effect of the truncation parameter δ on the non-paraxiality of the far-field is smaller.The difference between the non-paraxial and the paraxial results is independent of the beam order N.The far-field divergence angle of diffracted CFGBs first increases and then tends to a sutured value with increasing the f-parameter.With increasing the truncation parameter δ,the far-field divergence angle first decreases and then tends to a minimum value.The far-field divergence angle of diffracted CFGBs is nearly independent of the beam order N.

关 键 词：圆平顶高斯光束 远场特性 圆形光阑 衍射 

分 类 号：O43[机械工程—光学工程]