单探测器偏振相干层析信号的傅里叶变换分析

研究了生物组织的双折射率、质地密度及层次结构等不同特性对单探测器偏振相干层析(PS-OCT)信号傅里叶频谱的影响。探讨了单探测器PS-OCT的成像理论,建立了多层组织模型。以该模型为样品模拟了它的单探测器偏振OCT信号,并分析了不同模型参数对信号傅立叶频谱的影响。以牛软骨、新鲜及干牛腱为样品,利用单探测器PS-OCT系统对它们进行A型扫描,并对获得的数据进行傅里叶变换。获得的傅里叶频谱显示,随着样品双折射率、背散射率、结构层次等特性的改变,频谱中的谱峰形状及所对应的频率也发生变化,结果证实了单探测器PS-OCT系统检测多种生物组织特性的能力。

Fast Fourier transform analysis of single-detector polarization-sensitive optical coherence tomographic signals

This paper focused on the relationship of the biological tissue character and the Fast Fourier Transform(FFT) of Polarization-sensitive Optical Coherence Tomography(PS-OCT) signals,and researched the influence of the birefringence,texture and the structure of tissues on the FFT of PS-OCT signals. After describing the single-detector PS-OCT imaging theory in detail,it set up a three-layer tissue model. On the basis of the model,it simulated its single detector PS-OCT signals and analyzed the influence of different model parameters on the FFT of signals. By taking the bovine tendons and cartilages as samples,a A-scan experiment was carried out with the single detector PS-OCT system.Obtained FFT shows that the spectral shapes and relative frequencies change with the different tissue characters,such as birefringence,back scattering indexes and structures. The researches approve the ability of single-detector PS-OCT in detecting biological tissue characters.