强度相关场对比度测量准均匀介质散射势强度的理论研究

Theoretical Study on Determination of Strength of Scattering Potential of Quasi-Homogeneous Media by Visibility of Intensity Correlated Field

基于一阶玻恩近似条件,分别得到了标量和电磁平面波经过准均匀(QH)介质散射的二阶强度相关场对比度解析式。解析结果显示,对于标量平面波入射的情况,其对应的强度相关场对比度与散射势强度及比率D/R(D为光纤探头的口径,R为散射体至光纤探头的距离)有关。而对于电磁平面波入射情况,其对应的对比度与散射势强度、入射光偏振度及比率D/R均有关。此外,针对上述两种入射条件下的对比度数值受到各类参量的影响变化关系分别进行了数值仿真研究。仿真结果进一步表明,通过获取强度相关场的对比度数值并利用逆散射问题的求解,可以达到对准均匀介质散射势强度参量的反演和测量。理论结果对赝热光应用于光学相干层析术和鬼像实验中未知散射介质的测量有一定的潜在应用价值。

Within the accuracy of first-order Born approximation,the visibility of intensity correlated field is derived for two cases,i.e.,the scalar and electromagnetic plane wave scattering from quasi-homogeneous（QH） media,respectively.Analytical results indicate that the visibility of intensity correlated field depends on the strength of scattering potential and the ratio D/R for the scalar case,where D is the radius of fiber-optic probe,and R is the distance between the scatterer and the fiber-optic probe.Comparably,for the electromagnetic case,the corresponding visibility relates with the strength of scattering potential,polarization of incident waves and the ratio D/R.Furthermore,numerical simulations are performed to investigate the influences of above parameters on the mean value of visibility.Numerical results further reveal that the strength of scattering potential of QH media may be determined by solutions of the inverse scattering problem provided that the visibility of intensity correlated field is obtained from experiments.The results may provide potential applications for the reconstruction and determination of unknown scatterer in optical coherence tomography and ghost imaging using the pseudo thermal light.