推导了部分相干电磁光束经过杨氏双缝干涉后偏振度的表达式,研究了干涉光场偏振度的变化情况.结果表明,干涉光场偏振度不仅取决于双缝处的偏振度、相干长度,而且还取决于杨氏双缝缝宽.当所有相干长度都相等时,干涉光场偏振度不再发生变化,其值就等于双缝处的偏振度.着重分析了系统中交叉谱密度矩阵系数Bxy=Byx≠0的情况,并将结果与Bxy=Byx=0时作了比较.

The expression for the degree of polarization of partially coherent electromagnetic beams in Young′s double-slit interference field was derived.The behavior of the degree of polarization in the interference field was investigated.It is shown that the degree of polarization in the interference field not only depends on the degree of polarization in the slit and the coherence length,but also on the width of slit.When all the coherence length of partially coherent electromagnetic beams were chosen the same value,the degree of polarization will keep the same,which is equal to that in the slit.The attention is focused on the case of the cross-spectral density matrix coefficient Bxy=Byx≠0 and the results are compared with the cross-spectral density matrix coefficient Bxy=Byx=0 case.