基于P_3近似的空间分辨漫反射研究  

Study of Spatially Resolved Diffuse Reflection Based on P_3 Approximation

作　　者：高宗慧[1] 刘迎[1] 郭云峰[1] 田会娟[1] 

机构地区：[1]天津大学理学院光电信息技术科学教育部重点实验室,天津300072

出　　处：《光学学报》2006年第8期1220-1225,共6页Acta Optica Sinica

基　　金：国家自然科学基金(60278004)资助课题

摘　　要：光源附近组织的空间分辨漫反射是近年来生物医学光子学领域的一个研究热点,其目的是发展一种能够测定活体生物组织光学参量的新技术。漫射近似理论研究光源附近组织的空间分辨漫反射具有很大局限性。P3近似理论考虑了相函数的三阶矩,能较准确地描述光源附近组织的光辐射分布。研究了基于P3近似的空间分辨漫反射,从输运理论的PN方程组出发,导出了P3近似方程组和P3近似的格林函数解;阐述了漫射近似与P1近似的关系,给出了外推边界条件下,准直光束近似后的P3近似漫反射率的完整表示,讨论了相函数二阶参量对P3近似漫反射的影响,并与漫射近似和蒙特卡罗模拟结果进行了比较,指出了P3近似的应用范围。Spatially resolved reflection close to light source has drawn great attention in the fled of medical optics and photonics recently. This research is considered to develop a new noninvasive technique of measuring the optical properties of intravital biological tissue. It is limited to study the spatially resolved diffuse reflection of tissue close to light source with diffusion approximation. The radiance distribution close to light source can be analyzed by P3 approximation theory considering the third-order moment of phase function. The spatially resolved diffuse reflection based on P3 approximation is studied. The equation set of the P3 approximation and its Green function approximate solution are derived from the PN equation set of the transport theory. The relationship between P1 approximation and the diffusion approximation is demonstrated, and a complete solution of P3 approximation with the extrapolated boundary conditions and collimated beam approximation is obtained. The effects of the second-order parameter on the P3 approximation diffuse reflection are studied, and the results are compared with them of diffusion approximation and Monte Carlo simulation. The application range of P3 approximation is presented.

关 键 词：医用光学与生物技术 源和探测器微距 P3近似 漫反射 

分 类 号：Q631[生物学—生物物理学]