基于单相机的微米谱域偏振光学相干层析成像方法  

Micron Polarization-sensitive Spectral-domain Optical Coherence Tomography Based on Single Camera

作　　者：仇志远 高万荣[1] 陈朝良 常颖 QIU Zhiyuan;GAO Wanrong;CHEN Chaoliang;CHANG Ying(School of Electronic Engineering and Optoelectronic Technique,Nanjing University of Science and Technology,Nanjing 210094,China;School of Electronic Science&Engineering,Southeast University,Nanjing 210096,China)

机构地区：[1]南京理工大学电子工程与光电技术学院,南京210094 [2]东南大学电子科学与工程学院,南京210096

出　　处：《光子学报》2022年第12期221-230,共10页Acta Photonica Sinica

基　　金：中央高校基本科研业务费专项资金(No.30920010003);国家自然科学基金(Nos.61275198,60978069)。

摘　　要：提出一种基于单相机的偏振谱域光学相干层析方法。该方法基于全单模光纤光路,使用宽带光源实现微米纵向高分辨率成像性能。通过硬件和软件两方面对系统色散进行矫正补偿,提高系统的实际分辨率。为实现样本偏振态的测量,入射至样品表面及参考臂的光偏振态由偏振片和四个偏振控制器进行调制。此外,利用偏振片在不同时间的通道切换实现两正交通道光谱信号的分时探测。根据得到的正交光谱信息,计算重构样品强度图和相位延迟图。该系统成功实现了单相机的偏振OCT测量,通过获取离体生物组织的强度图和相位延迟图验证了系统的成像能力。该方法为实现小型化在体高分辨偏振成像打下基础。Optical Coherence Tomography(OCT)is an interferometric imaging method,and it is mostly used in the field of imaging for its non-invasive,high-resolution and high-speed properties.This technology can also be applied to detect defects in materials.Although OCT can provide images of morphological structure,it can not distinguish tissues with similar light intensity properties in pathologies.Polarization-sensitive Optical Coherence Tomography(PS-OCT)is an imaging system extended from conventional OCT,enabling functional imaging.It can use Stokes parameters,Jones and Muller matrices to calculate the polarization properties of the samples,like the birefringence phase retardation,the optic axis orientation and depolarization.PS-OCT has been used in a number of medical applications,such as burn depth determination and tumor yield assessment.And it also can be applied to examination of stress-induced birefringence of materials.In previous systems,it is required to detect the two orthogonally polarized components by using dual cameras based spectrometers.But there are problems with this system arrangement.For example,it has high cost and requires complex hardware and software designs.In addition,it is hard to achieve the uniform detection for two cameras,the mismatch between the two channels can lead to polarization distortions and failure to calculate the true information and additional algorithms are necessary to tackle it.So a series of single cameras based methods have been proposed.Single cameras based systems can achieve time-sharing detection or real-time detection of two orthogonal channels with relatively lower cost and simpler system setup.Wollaston prism,optical switch,grating and multi-camera are often used to achieve single camera detection.Improving the axial resolution of the system can enable it to have more potential applications.The OCT system with micron axial resolution can achieve cellular and subcellular level imaging and detect subsurface defects in ceramics or other materials.In order to achieve suc

关 键 词：生物医学成像 偏振敏感光学相干层析 单相机探测 色散补偿 

分 类 号：TN247[电子电信—物理电子学]