频域光学相干层析术成像深度提高方法研究
发布时间：2019-02-14 13:34
【摘要】：在频域光学相干层析(Spectral Domain Optical Coherence Tomography,SDOCT)系统中,为了在横向和纵向两个方向均获得高的分辨率,需要采用大数值孔径的物镜。这时,仅位于物镜焦深范围内的结构有高横向分辨率,在焦外分辨率降低。干涉合成孔径显微术(ISAM)是一种三维图像重构算法,可以消除离焦区的图像模糊,达到在所有成像深度中都可以获得焦平面处的横向分辨率的效果,可以解决SDOCT中系统的横向分辨率和成像深度之间的矛盾。本文分析了 ISAM重构算法的原理和适用的范围,对比分析了传统SDOCT成像算法和经过ISAM重构算法处理的成像图像结果。为了减少算法运算时间,本文将非均匀傅里叶变换(NUFFT)引入了 ISAM算法,实验结果表明了该方法节省了算法的运算时间,给实时成像高分辨率SDOCT系统成像提供了基础。其次,为了检测光学元件的亚表面损伤,将全内反射法(TIRM)和SDOCT两套系统联合来进行检测和评估分析,本文提出了一套标定和测量的方法并进行了实验。实验通过标定双系统的探测臂位置使之可以对同一点先进行粗定位后进行精确的层析成像,得到对亚表面损伤进行表征的参数。
[Abstract]:In the frequency-domain optical coherence tomography (Spectral Domain Optical Coherence Tomography,SDOCT) system, in order to obtain high resolution in both transverse and longitudinal directions, a large numerical aperture objective is needed. In this case, the structure located within the focal depth of the objective lens has a high lateral resolution and a lower resolution outside the focal point. Interferometric synthetic aperture microscopy (ISAM) is a 3D image reconstruction algorithm, which can eliminate the image blur in the defocus region and achieve the effect that the horizontal resolution of the focal plane can be obtained in all imaging depths. It can solve the contradiction between lateral resolution and imaging depth in SDOCT. In this paper, the principle and application range of ISAM reconstruction algorithm are analyzed, and the results of traditional SDOCT imaging algorithm and image processed by ISAM reconstruction algorithm are compared and analyzed. In order to reduce the computational time of the algorithm, the non-uniform Fourier transform (NUFFT) is introduced into the ISAM algorithm. The experimental results show that the algorithm saves the computation time and provides the basis for real-time imaging of high-resolution SDOCT system. Secondly, in order to detect the subsurface damage of optical elements, the total internal reflection method (TIRM) and SDOCT are combined to detect and evaluate the subsurface damage. In this paper, a set of calibration and measurement methods are proposed and the experiments are carried out. By calibrating the position of the detecting arm of the two systems, the parameters of the subsurface damage can be obtained by the initial coarse location of the same point and the accurate tomography.
【学位授予单位】：南京理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TP391.41
本文编号：2422251
[Abstract]:In the frequency-domain optical coherence tomography (Spectral Domain Optical Coherence Tomography,SDOCT) system, in order to obtain high resolution in both transverse and longitudinal directions, a large numerical aperture objective is needed. In this case, the structure located within the focal depth of the objective lens has a high lateral resolution and a lower resolution outside the focal point. Interferometric synthetic aperture microscopy (ISAM) is a 3D image reconstruction algorithm, which can eliminate the image blur in the defocus region and achieve the effect that the horizontal resolution of the focal plane can be obtained in all imaging depths. It can solve the contradiction between lateral resolution and imaging depth in SDOCT. In this paper, the principle and application range of ISAM reconstruction algorithm are analyzed, and the results of traditional SDOCT imaging algorithm and image processed by ISAM reconstruction algorithm are compared and analyzed. In order to reduce the computational time of the algorithm, the non-uniform Fourier transform (NUFFT) is introduced into the ISAM algorithm. The experimental results show that the algorithm saves the computation time and provides the basis for real-time imaging of high-resolution SDOCT system. Secondly, in order to detect the subsurface damage of optical elements, the total internal reflection method (TIRM) and SDOCT are combined to detect and evaluate the subsurface damage. In this paper, a set of calibration and measurement methods are proposed and the experiments are carried out. By calibrating the position of the detecting arm of the two systems, the parameters of the subsurface damage can be obtained by the initial coarse location of the same point and the accurate tomography.
【学位授予单位】：南京理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TP391.41
【参考文献】
相关期刊论文 前10条
1 刘浩;高万荣;陈朝良;;手持式牙齿在体谱域光学相干层析成像系统研究[J];中国激光;2016年02期
2 王玲;涂沛;石然;徐铭恩;;光学相干层析成像技术用于三维生物打印水凝胶支架结构的定量评价研究[J];中国激光;2015年08期
3 李培;孔雪;孙沁园;陈朝良;高万荣;;基于图像频谱能量集中度的频域光学相干层析术数值色散补偿[J];激光与光电子学进展;2014年11期
4 卞海溢;高万荣;张仙玲;陈朝良;;基于观察矩阵的频域光学相干层析成像图像重构算法[J];光学学报;2014年02期
5 张仙玲;高万荣;卞海溢;卢邱生;;基于经验模式分解法的光学相干层析成像去噪研究[J];光电子.激光;2012年03期
6 刘健;马占龙;王君林;;光学元件亚表面损伤检测技术研究现状[J];激光与光电子学进展;2011年08期
7 李鹏;黄润;高万荣;;光学相干层析术在人体皮肤成像方面的实验研究[J];中国激光;2009年10期
8 李鹏;高万荣;;光学相干层析系统的信噪比分析及优化[J];中国激光;2008年04期
9 吴东江;曹先锁;王强国;王奔;高航;康仁科;;KDP晶体加工表面的亚表面损伤检测与分析[J];光学精密工程;2007年11期
10 张银霞;单晶硅片超精密加工表面\亚表面损伤检测技术[J];电子质量;2004年07期
，本文编号：2422251
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