基于光开关的单光谱仪频域偏振光学相干层析成像系统

Single camera spectral domain polarization-sensitive optical coherence tomography using an optical switch

提出一种基于光开关的单光谱仪频域偏振光学相干层析成像(PSOCT)方法。在参考臂通过1×2路光开关把参考光分成两路,并在其中一路光路中放置1/4波片(QWP),从而在参考臂构建出一对正交的偏振光。利用光开关进行参考臂正交偏振光不同通道的选择,水平和垂直偏振光轮流返回与样品光发生干涉,实现偏振干涉信息的分时探测,再通过探测到的两路偏振干涉信息计算得到测量样品的相位延迟图以及强度图。本文方法实现了偏振光学相干层析成像系统的单光谱仪探测,得到了离体鸡脚蹄筋组织的强度图以及相位延迟图,能够实现高速偏振成像。

We demonstrate a simple spectral-domain polarization-sensitive optical coherence tomography （SD-PS（X;T） using a single line-scan camera based on a high-speed light switch. A 1 × 2 light switch splits the reference beam into dual arms,and orthogo^al polarization light rays are constructed by a quarter-wave plate （QWP）. The reflected horizontal and vertical polarization light rays are delivered via an optical switch to a single spectrometer by turns. The relative reflectivity and retardance information are available by recombining the two orthogonal polarization images. This approach does not require addi- tional intricate devices or algorithms to separate the orthogonally polarized images and can eliminate the crosstalk between the orthogonally polarized light by independent detection. We obtain the PSOCT image of a chicken feet sinew sample in vitro. This system can be employed to acquire high speed polarizationsensitive OCT images.