基于光学相干层析成像技术的薄膜厚度测量

为了对薄膜厚度进行测量,采用白光谱域光学相干层析成像的测量方法,进行了理论分析和实验验证,对以玻璃为基片的单层和多层薄膜样品进行了层析成像实验,获得了样品的2维层析图像。结果表明,该系统不仅能显示薄膜样品内部的微观结构,而且能从2维层析图像中得到单层和多层薄膜的厚度(分别为68μm和30μm),测量值与理论值相吻合,从而验证了测量理论正确性。该系统具有较高分辨率,可实现快速成像,满足实际工业测量需要。     

光学相干层析成像用于微机电系统测量研究

为了对硅V型槽的结构进行测量,采用热光源谱域光学相干层析成像法,进行了理论分析和实验验证,取得了硅V型槽的1维深度和2维层析图像,获得了硅V型槽的深度、上部宽度和底部宽度数据分别为145.38m,212m和32m。结果表明,该测量结果与扫描电子显微镜测量值基本一致。这对微机电系统结构测量是有帮助的。     

Real-time digital signal processing-based optical coherence tomography and Doppler optical coherence tomography

We present the development and use of a real-time digital signal processing (DSP)-based optical coherence tomography (OCT) and Doppler OCT system. Images of microstructure and transient fluid-flow profiles are acquired using the DSP architecture for real-time processing of computationally intensive calculations. This acquisition system is readily configurable for a wide range of real-time signal processing and image processing applications in OCT.     

基于医用显微镜的光学相干层析系统设计

设计了以医用显微镜为探头的光学相干层析(OCT)系统,实验结果表明系统纵向分辨率为18μm,横向分辨率小于20μm.通过三维图象重构,获得了霉菌感染裸鼠皮肤结痂部分的三维组织结构,在皮肤科研究具有重要应用价值.     

Anatomical optical coherence tomography for long-term, portable, quantitative endoscopy

In this paper, we report on anatomical optical coherence tomography, a catheter-based optical modality designed to provide quantitative sectional images of internal hollow organ anatomy over extended observational periods. We consider the design and performance of an instrument and its initial intended application in the human upper airway for the characterization of obstructive sleep apnea (OSA). Compared with current modalities, the technique uniquely combines quantitative imaging, bedside operation, and safety for use over extended periods of time with no cumulative dose limit. Our experiments show that the instrument is capable of imaging subjects during sleep, and that it can record dynamic changes in airway size and shape.     

光学相干层析成像技术的应用

介绍了光学相干层析成像技术在不同领域的应用,预言了未来的发展趋势。     

基于频域OCT的生物组织折射率测量研究

提出了一种利用频域光学相干层析系统测量生物组织折射率的方法.与时域OCT下的光程匹配法相比,该方法充分地发挥了频域OCT测量速度快的优势,只需要在放置样品前后进行两次干涉光谱测量,经傅立叶变换等数据处理后即可得到折射率.测鞋过程简单,操作简便,测量速度快,极大地缩短了样品在空气中暴露的时间,提高了测量的准确性.利用该方法测量了标准样品熔石英及真实样品黄瓜浅表层1 300 nm波长下的折射率,验证了该方法的有效性和可靠性.     

应用OCT成像技术对海水珍珠的无损测量研究

为探明两种不同大小的海水珍珠的内部结构差异,利用一种新型扫频光学相干层析（OCT）成像系统和Raman光谱仪,无损分析了中国南珠和南洋珠两类海水珍珠。Raman光谱分析表明,这批海水珍珠主体物相皆为文石,未检测到人工有机染色物和添加物。基于该OCT成像系统的测量和图形处理功能,对这批海水珍珠珠层厚度进行了快速、有效的测量,并根据珠层厚度,将其质量等级分成五等。对比分析了这批海水珍珠样品的厚度与直径,除少数样品外,这批海水珠层厚度与珍珠直径呈弱正相关。此外,通过OCT二维图像的纹理特征,对这批海水珍珠的珍珠层、过渡层、珠核层组织的均匀性等进行了归类和评估。OCT成像技术可为珍珠的珠层厚度和均匀性质量分级提供重要依据。     

光学相干层析成像技术研究

文章主要阐述了光学相干层析技术作为一种有别于其他层析成像技术的新型技术手段,具有快速、实时、无损等特点。它能利用低相干光的干涉,将带有生物样品信息的相干光进行解调、滤波和放大后成像。文章主要从光学相干层析技术的背景、定义、原理及其在现代医学领域的应用和未来的发展方面进行研究。     

全光纤光学相干层析系统用于人造指纹的识别

目前商用指纹识别系统由于仅依赖于手指表面二 维图像的脊模式和细节特征进行识别,对人造 指纹有极大的安全漏洞。本文提出一种利用光学相干层析(OCT)技术识别 人造指纹的方法。在分析OCT系统原理及皮肤光学特性的基础上,使用研制的全光纤OCT系 统分别对 人体手指以及被商用指纹识别系统识别通过的人造指模进行成像,获得了二者的二维OCT图 像和对应的一 维信号,同时获得人造指模的三维OCT图像,通过对比分析二者深度方向 上的微结构信息 以及光学特性可以准确地识别出人造指模。实验结果表明,OCT技术不仅可以用于指纹的防 伪,有效地提高生物特征识别系统的安全性能,而且还具有用于指纹识别的潜力。     

Research on full-field optical coherence tomography

Full-field optical coherence tomography(FFOCT)was used for imaging the interior part of an object.Firstly,the mathematical modeling and performance analysis of the FFOCT system mounted was provided.Secondly,images of several different human tissues were obtained by FFOCT system,including esophagus,uterus,etc.The images of different depths of the same tissue were shown and compared.It was the first time in China that FFOCT was used for generating depth images on human esophagus and uterus;high-resolution images had been obtained for different depths without cutting the tissue sample,in which intercellular substance and myofibril structure could be clearly identified.As the in-depth structure could be imaged without the process needed for frozen and paraffin sectioning methods,the technology could been highly valuable for early cancer diagnosis and pathological analysis in tumor research.     

OCT无创检测技术的人体血糖平衡延迟时间研究

为了研究在人体血糖快速变化情况下,皮肤组织液糖浓度与血液(指血、静脉血)中血糖变化的延迟关系,采用光学相干层析技术,通过人体口服葡萄糖耐量测试和血糖钳夹实验,测量了随血糖变化的皮肤光衰减系数,并对人体血糖平衡延迟时间问题做了研究。为了避免由于延迟因素造成预测血糖值误差过大,选择700m ~800m以下皮肤深度的真皮网状层作为分析计算区域。结果表明,延迟时间一般随着皮肤区域深度的增加而缩短;在不同的皮肤深度区域,血糖平衡延迟时间存在一定的差异性。此研究有助于提高光学无创血糖检测的准确性和可靠性。     

光学相干层析成象技术基本原理

本文介绍了光学相干层析成象技术（ＯＣＴ），阐述了层析成象的基本原理，讨论了层析象的信息内容。     

光学相干层析系统的成像数学模型研究

生物组织样品的光学特性可以由光学相干层析成像系统探测到的后向散射功率确定，文中建立了入射光线在样品介质内的一阶散射数学模型，揭示了样品的衰减系数和后向散射系数与系统探测结果之间的关系。     

Stress-location measurement along an optical fiber by synthesis oftriangle-shaped optical coherence function

A triangle-shaped optical coherence function is synthesized, and is applied to real-time stress-location measurement along an optical fiber. We utilize a polarization-maintaining fiber (PMF) as the sensing element. Stress-induced coupling from one eigenpolarization mode to the other is used as the sensing mechanism. The stress-position on PMF linearly corresponds to the delay difference between the two eigenpolarization modes, which is measured with a slope of the synthesized triangle coherence function. The degree of coherence changes linearly from one to zero with respect to the delay difference. By extracting the coherence value, the stress point is figured out in real time     

Image enhancement in optical coherence tomography usingdeconvolution

A linear shift invariant system model describing coherent light-specimen interactions in optical coherence tomography is presented. Based on this model, an iterative deconvolution algorithm is demonstrated for enhancing the sharpness of optical coherence tomographic images of biological structures     

采用频域光延迟线的光学相干层析成像

频域光延迟线是一种光学扫描结构,其基本组成是一个衍射光栅、一个透镜和一个扫描镜.把频域光延迟线应用到光学相干层析成像系统中,可以使参考臂扫描速率至少达到数m/s以上,从而实现视频速率的图像获取.从几何光学的角度分析了频域光延迟线的工作原理,分析结果表明在扫描角很小的情况下,入射光的光程或相位变化频率与扫描角频率有较好的线性关系.基于这一结构的光学相干层析成像的结果证明可以避免活体生物组织位移引入的图像模糊.另外,还提出了一种基于微执行器的新扫描装置.     

谱域光学相干层析测量技术研究

介绍了一种基于谱域光学相干层析成像的光学测量技术,对其基本原理进行了分析,并通过平面镜位移实验对该理论进行了验证。实验结果表明,该方法测得的数值与理论值基本一致,表明谱域光学相干层析成像技术的测量结果真实可靠,可以为高散射物体的表面轮廓测量和低散射物体的内部结构成像提供技术支撑。     

光学相干成像图像获取新技术研究

根据光学相干层析成像(OCT)的基本原理,通过在系统中添加一个作为参考的光纤迈克尔逊干涉仪,替代了全场OCT系统中通常采用的扫描参考光路、设计了一种可以有效地保障系统长期稳定的技术方案,并在实验室中获得了良好的试验效果.     

Distributed fiber-optic stress-location measurement by arbitrary shaping of optical coherence function

A functional distributed fiber-optic stress-location measurement technique by arbitrary shaping of the optical coherence function has been demonstrated. The technique measures the distribution or location of stress-induced polarization mode coupling in a polarization-maintaining fiber by manipulating the optical coherence function. The location of applied stress is given by optical path difference between the two polarization modes, which is determined by the synthesis of the coherence function. Three types of coherence function-a scanning peak, a scanning low-sidelobe peak, and a standing triangle-have been synthesized experimentally and used for stress locating. When using the coherence function of scanning peak, the coherence peak is slid to scan over the measurement range by a phase modulation to obtain the stress distribution; when using the triangular coherence function, the detection range is set within a linear slope of the triangle so that the stress location is directly converted into the value of the coherence degree.