【摘要】 文章基于非傍轴矢量光束横截面上光强的严格定义〈S_z〉,采用桶中功率定义光束的束宽、远场发散角以及M²因子。以截断非傍轴矢量高斯光束为例,对光束的传输特性进行了详细的理论分析和数值计算,并与非傍轴标量理论的结果进行了比较分析。数值计算表明,束腰半径W （0）<λ时,传输特性的矢量描述与非傍轴标量描述有显著差别。当截断参量R/ω₀<0.5时,截断高斯光束的传输特性与截断平面波的传播趋于一致;当截断参量R/ω₀>2时,过渡到自由高斯光束的传播。更多还原

【Abstract】 Based on the rigorous definition of light intensity of nonparaxial vectorial beams in the transverse plane（〈S_z〉）,beam width,far-field divergence angles and M² factors are defined by the power in the bucket.Taking truncated nonparaxial vectorial Gaussian beam as an example,the detailed theoretical analyses and numerical calculations about the propagation characteristics are performed,and the results are compared with those from the nonparaxial scalar theory.Numerical calculations show that when the beam waist W（0）<λ,there are obvious differences between the propagation characteristics described by nonparaxial scalar and vectorial theory.When the truncation parameter R/ω₀<0.5,the propagation characteristics of truncated nonparaxial vectorial Gaussian beams trend to those of truncated plane waves.Meanwhile,when R/ω₀>2,truncated nonparaxial vectorial Gaussian beams follow the same propagation laws of free Gaussian beams.更多还原