椭圆矢量高斯光束多孔衍射的光强分布

摘要

Objective— To analyze the fine structure of multi-rectangular aperture singular beams. Methods—Based on vector Rayleigh-Sommerfeld diffraction integrals,the light intensity distribution of the elliptical vectorial Gaussian beams diffracted at a tri-rectangular aperture is studied.It mainly discusses the variation regularities on-axis,off-axis and transverse intensity distribution of the Poynt-ing vector 〈Sz 〉.Results—The results indicate that,for the on-axis situation,the parameter f plays an important role in the light intensity distribution of the elliptical vectorial Gaussian beams,Δ andΛ can also affect beams evolution behavior.For the off-axis situation,the isocandela curve on the transver-sal space is ellipse at the beginning,and becomes circular when z/λ=2.459 1,converts into ellipse a-gain with long axis and short axis turning their position,which is confirmed by transverse isocandela curve.Conclusion—Therefore,the quality of the light beams transmission can be controlled by choo-sing reasonable optical parameters.%目的：分析奇异光束多孔衍射的精细结构。方法基于矢量瑞利-索末菲衍射积分公式，研究矢量椭圆高斯光束三孔衍射的光强分布。主要讨论在轴上、离轴和不同横截面处，精确光强表达式波印廷矢量〈S z 〉的变化规律。结果分析表明：在共轴情况下，参数 f 对〈S z〉的影响起重要作用，Δ和Λ也能影响光强的演变。而对于离轴情况，在其横截面上，等光强线先是椭圆，在 z／λ＝2．4591时，变为圆形，而后又变成椭圆，但其长、短轴方向交换了位置，通过横向光强等高线，可以更清楚地看出光波的这种演化规律。结论可以通过合理选择光学参数，控制多孔衍射对光束传输质量的影响。