在多层结构的生物组织中近红外光子迁移的研究

在无损近红外光学诊断领域中，研究光子在多层生物组织中的迁移十分重要。本文以猪的脂肪和肌肉组成的两层结构作为研究的样品。将近红外光源和检测器置于脂肪的表面，由光源发出被两层组织反射的光子的一部分由检测器所接收。本文给出了光电流与光源到检测器的距离的关系以及光电流与脂肪厚度的关系。为了分析实验结果，用蒙特卡罗仿真计算光子在均匀介质中迁移轨迹，用菲涅耳定律来决定光子包在脂肪和肌肉边界处的折射分量和反射分量。结果表明，仿真数据与实验符合得很好。结论是：本文中所提供的实验和仿真方法对于分析光子在生物组织中的迁移以及优化传感器设计十分有用。

Research on the Near-infrared (NIR) Photon Migration in Multi-layered Structures of Biological Tissues

The phenomena of photon migration in multi-layered structures of biological tissue is very important in the field of non-invasive near-infrared optical diagnosis. In this paper, a two-layered structure consisting of the fat and the muscle of poke was used as the sample. Near-infrared light source and detector were located on the surface of the fat and a part of the photons reflected by the two-layered structure of the tissue were detected. The relationship between the optical current and the distance from source to detector and the relationship between the optical current and the thickness of the fat layer were given. In order to analyze the experiment results, Monte-Carlo simulation was used to calculate the photons migration traces in the uniform tissues and the Fresnel's law is used to determine the refraction and reflection components of a photon package at the boundary between the fat and the muscle. The results showed that the simulation data coincident well with the experimental results. The conclusion is that the experiment and the simulation method provided in this study may be useful to analyze the photon migration in a mult-layered tissue and to optimize the design of the transducer.