交叉偏振图像不但可以反映样品的偏振敏感结构信息,而且可以更好地反映出样品浅表层的微结构。因此利用光学相干层析成像技术(OCT)获取样品的交叉偏振图像越来越受到人们的关注。在前人的基础上,实现了一种基于单模光纤的新型全光纤交叉偏振光学相干层析成像系统(CP-OCT),该系统具有同时获得样品的交叉偏振信号和同向偏振信号的功能。详细介绍了CP-OCT系统信号的形成原理,并使用琼斯矩阵理论推导出交叉偏振信号和同向偏振信号的表达式。使用CP-OCT系统分别对玻璃片、中心波长为1310nm的λ/4波片及在体皮肤进行成像,从实验上验证了全光纤CP-OCT系统具有同时获取样品偏振敏感结构与偏振不敏感结构信息的能力。
Cross-polarized image can provide both polarization-sensitive information and a more clear sub-surface structure of the sample. As a result, getting the cross-polarized image by using optical coherence tomography (OCT) becomes more and more popular. A novel fiber-based cross-polarized optical coherence tomography (CP-OCT) system is implemented, which is capable of acquiring both cross-polarized signal and co-polarized signal of a sample simultaneously. Forming principles of both cross-polarized and co-polarized signals are described, and the expressions of them are derived using Jones matrix. The images of a glass slide, aλ/4 wave plate at a wavelength of 1310 nm, and vivo skin obtained with the system confirm that CP-OCT can provide both polarization-sensitive and polarizationinsensitive informations of the sample.