摘要光学相干层析成像术(Optical Coherence Tomography, OCT)是一种新型的非侵入扫描成像方式。OCT基于迈克尔逊干涉仪,以低相干光照明,样品上后向散射光与参考镜反射回来的光只有在其光程差位于相干长度以内才发生干涉。对返回的干涉信号进行解析,以获样品的两文层析图像,进而由计算机合成三文图像。采用频谱编码(spectrally encoded)OCT成像,在获得高分辨率、高帧率图像的同时,可显著减小成像系统的口径,在生物医学成像领域具有极大潜力。本文首先介绍OCT技术的发展与应用以及该技术的理论基础,并介绍了国内外频谱编码内窥术的发展及应用,然后讨论了频谱编码成像系统的原理、结构和性能参数,并结合实验系统,分析了影响成像质量的因素。20323
关键词 频谱编码 光学相干层析 高分辨率快速成像 光谱仪
毕业论文设计说明书(论文)外文摘要
Title Study of Imaging performance analysis and experimental research on spectrally encoded imaging system
Abstract
Optical Coherence tomography (OCT) is a new type of noninvasive scanning imaging technique. OCT is based on Michelson interferometer illuminated by a low-coherent light. Only path length difference of the light reflected from the reference mirror and backscattered from within the sample is within the coherence length that can generate the interference signal. Cross-sectional images of objects can be calculated analyzing the interference signals,and three-dimensional image may be reconstructed through computer. The spectrally encoded-based OCT makes it possible to obtain images of specimens with high three-dimensional resolution at a large frame-rate, and at the same time significantly reducing size of the probe, showing great potential in the field of biomedical imaging. In this thesis, first of all the theoretical base of and development and applications of OCT technique and the spectrally encoded optical imaging system were described. The theory, arrangement and performance parameters of spectrally encoded imaging system were then discussed in details. Factors that affect the image quality of experimental spectrally encoded imaging systems were analyzed.
Keywords spectrally encoded, optical coherence tomography (OCT), quick high-resolution imaging, spectrometer
目 次
1 绪论 1
1.1 OCT的发展与应用 1
1.2 OCT理论基础 4
1.3 时域与频域OCT 6
1.4 传统OCT缺陷性及新型方法提出 7
1.5 频谱编码发展概况 8
2 频谱编码理论 12
2.1 频谱编码内窥的提出 12
2.2 频谱编码内窥镜SEE的理论分析 12
2.3 成像光谱仪 14
2.4 频谱编码深度分辨率 16
2.5 信噪比 19
2.6 系统光学参数 20
2.7 本章小结 26
3 频谱编码系统实验部分 27
3.1 实验原理图 27
3.2 实际实验系统结构图 28
3.3 系统参数分析 29
3.4 实验结果及分析 31
结论 34
致谢 35
参考文献 36
1 绪论
光学相干层析(Optical Coherence Tomography,简称OCT),是一种新兴非侵入扫描成像方式,现主要应用于医学成像中[1]。光学相干层析成像技术,以迈克尔逊干涉仪的原理为基础,基于生物组织的光学窗口(即其对近红外区光,是穿透深度达到最大值的波长区间),利用远红外低相干光源照明。运用从生物组织的散射光中与参考光进行干涉的方法,利用干涉信号计算出物体的内部分层信息,即对其内部进行断层成像,实现非侵入式三文实时成像[2]。近年来,OCT成像技术因其成像分辨率高、所需功率小以及辐射作用弱等临床医学方面的显著优势得到了飞速发展。 频谱编码成像系统的成像性能分析与实验研究 :http://www.751com.cn/tongxin/lunwen_12059.html