复变量双曲余弦平方-高斯光束的双焦开关  

Double Focal Switch of Elegant Cosh-squared Gaussian Beams

作　　者：郝中骐[1] 刘莉[1] 

机构地区：[1]宜春学院物理科学与工程技术学院,江西宜春336000

出　　处：《宜春学院学报》2008年第4期41-42,84,共3页Journal of Yichun University

摘　　要：推导了复变量双曲余弦平方-高斯光束(EchSGB)通过无光阑透镜系统后的轴上光强分布公式,在此基础上通过大量的数值分析发现,在菲涅耳数较小的情形下,当光束参数a<0.91且b>1时,轴上焦点出现两次位置不同的跃变-双焦开关(DFS)现象,讨论了光束入射距离及光束参数对其产生和变化的影响。最后对该光束的特例-余弦平方高斯光束的DFS现象作了一些分析讨论。The formula predominating the distribution of axial intensity of elegant cosh - squared Gaussian beams （EchSGB） through a lens without aperture is derived first. Base on large numbers of numerical calculation results, it is found that there may take place twice effective permutation of the focal point when a 〈 0. 91 and b 〉 1 for a lower Fresnel number, this new effect is called double focal switch （DFS） here. And the factors affecting the appearance and transformation of DFS are discussed later. At last, some discussions are given to cosine - squared Gaussian beams, as one of special cases of the beams.

关 键 词：复变量双曲余弦平方-高斯光束 双焦开关 无光阑透镜 余弦平方-高斯光束 

分 类 号：O435[机械工程—光学工程]