偏振空间频域成像系统及仿体验证  

Polarization Spatial Frequency Domain Imaging System and Phantom Verification

作　　者：石志国 张洋 王全福 李忠胜 王霞 董美丽 倪敬书 黄尧 张盛昭 王贻坤 张元志 Shi Zhiguo;Zhang Yang;Wang Quanfu;Li Zhongsheng;Wang Xia;Dong Meili;Ni Jingshu;Huang Yao;Zhang Shengzhao;Wang Yikun;Zhang Yuanzhi(Department of Biomedical Engineering,Anhui Medical University,Hefei 230009,Anhui,China;Anhui Provincial Engineering Technology Research Center for Biomedical Optical Instrument,Anhui Provincial Engineering Laboratory for Medical Optical Diagnosis&Treatment Technology and Instrument,Anhui Institute of Optics and Fine Mechanics,Hefei Institutes of Physical Science,Chinese Academy of Sciences,Hefei 230031,Anhui,China)

机构地区：[1]安徽医科大学生物医学工程学院,安徽合肥230009 [2]中国科学院合肥物质科学研究院安徽光学精密机械研究所,安徽省生物医学光学仪器工程技术研究中心,安徽省医用光学诊疗技术与装备工程实验室,安徽合肥230031

出　　处：《中国激光》2023年第9期25-33,共9页Chinese Journal of Lasers

基　　金：安徽省重点研究与开发计划(202004a07020016)、中国科学院合肥物质科学研究院院长基金(YZJJ2021GCH05)、安徽省食品药品监督管理局科技创新项目(AHYJ-KJ-202114)。

摘　　要：偏振光学成像是一种非标记、无损伤的检测技术,对亚波长微观结构的变化比较敏感,可以提供丰富的组织结构和光学信息。然而,在可见波段范围内,生物组织是强散射介质,光在组织中传播时会经历多次散射,失去原本携带的相位和偏振信息,从而影响光学成像的对比度和分辨率。本团队结合空间频域成像和偏振光学成像方法,搭建了偏振空间频域成像系统。通过高频空间频域成像控制照明光的穿透深度,利用穆勒矩阵表征样品浅层的偏振参数,进而反映样品浅层的微观结构信息。实验结果显示:偏振空间频域成像系统测得的灰阶板漫反射率与标准值线性相关(R2=0.99988);退偏系数与脂肪乳体积分数成正比关系,二向衰减系数随二向衰减器导致的二向衰减增大而增大;该系统可以准确测量四分之一波片和全波片的相位延迟,表明该系统可以准确测量样品的偏振参数。对比传统偏振光成像和偏振空间频域成像结果可以发现,偏振空间频域成像可以有效控制成像深度,精确测量样品浅层的穆勒矩阵。采用该系统对烧伤猪皮进行检测,测量结果显示:猪皮组织内部的胶原蛋白结构被破坏,相位延迟降低。本研究结果预期能够有效提升浅层组织偏振特性检测的准确性,促进肿瘤的早期检测。Objective The Muller matrix,as a method for characterizing the polarization properties of samples,contains complete information about the polarization properties of samples,and it has become an important indicator for characterizing pathological tissues in basic and preclinical studies.However,in the traditional polarized light imaging method for measuring the Muller matrix,the scattering depth of polarized light in collagen tissue cannot be controlled.The obtained Muller matrix information is the average of unknown depths in collagen tissue,and it is impossible to accurately measure the Muller matrix information of the pathological tissue area.Polarized spatial frequency domain imaging(PSFDI),which combines spatial frequency domain imaging(SFDI)and polarized light imaging,is applied to measure the optical properties of biological tissues accurately.Methods SFDI relates the spatial frequency of the projected stripe pattern to the penetration depth of the detected light,and the imaging depth can be controlled by controlling the spatial frequency of the projected light.We designed and validated a polarization SFDI system that uses the SFDI technique to control the imaging depth,projects the streak pattern onto the surface of the measured tissue,constructs a polarizer and detector to modulate the polarization state of the polarized light,and then acquires the image data using a CMOS camera and calculates the Mueller matrix information.Results and Discussions Experimental results showed that the grey-scale plate diffuse reflectance measured by the polarization SFDI system was linearly correlated with the standard value(R2=0.99988).The depolarization coefficient tends to be proportional to the fat emulsion volume fraction,the two-way attenuation coefficient increases with the increase of two-way attenuation owing to the two-way attenuator,and the accurate measurement of the phase delay of the quarter-wave and full-wave plates indicates that the system can accurately measure the sample polarization parameters.A compari

关 键 词：生物光学 偏振光学成像 空间频域成像 穆勒矩阵 组织仿体 

分 类 号：R318.51[医药卫生—生物医学工程]