基于随机电磁光束的相干偏振统一理论和部分相干光的传输定律,研究了部分相干光源所发出的光经过多个圆孔衍射后的偏振度变化情况。以高斯-谢尔(Gauss-Schell)模型光束为例,研究了多个圆孔衍射后的轴上偏振度变化。发现随着圆孔数量的增加,偏振度将出现相应的变化,并且经过足够长的传输距离之后,偏振度将趋于一个定值。以三个圆孔为例,重点研究了圆孔大小、圆孔间距、源平面处的相干长度以及源平面的偏振度取值等参量对轴上观察点的偏振度影响。

Based on the unified theory of coherence and polarization of random electromagnetic beams and the propagation law of partially coherent light, the change in the degree of polarization of beams which is generated from a partially coherent source after passing through a series of circular apertures was investigated. Gaussian Schell-model beam was taken as an example to study the change in the degree of polarization for on-axial points. It is found that, with the increase of the number of circular apertures, the degree of polarization for on-axial points will change. It is shown that for a sufficiently long propagation distance, the degree of polarization for on-axial points will tend to a certain value. And three circular apertures are chosen as a typical multiple circular apertures system for investigating change in the degree of polarization. It is shown that, the change in the degree of polarization depends on the size of circular apertures, the distance between circular apertures, the correlation length in the source plane and the degree of polarization in the source plane.