用双点源δ-P1近似光学模型反演生物组织的光学参量  

Use of the two-point-source δ-P_1 approximation model for recovery of optical parameters in biological tissue

作　　者：齐贝贝[1] 刘迎[1,2] 贾光一[1] 刘小君[2] 

机构地区：[1]天津大学理学院,天津300072 [2]天津大学精密仪器与电子工程学院,光电信息技术科学教育部重点实验室,天津300072

出　　处：《物理学报》2011年第12期633-639,共7页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:60278004)资助的课题~~

摘　　要：根据空间分辨漫反射的双点源δ-P1近似理论模型,采用非线性最小二乘法,从反射率的测量数据中反演得到了生物组织的吸收系数μa、有效散射系数μ's和二阶参量γ.研究表明,在光源与探测器之间距离大于一个输运平均自由程的情况下,双点源δ-P1近似能较好地描述光源附近的光辐射分布,而且能够根据参量γ与μ's的关系得到组织的各向异性因子g.这些研究对于生物组织的光学性质测量以及漫反射光谱技术的应用具有重要意义.Based on a theoretical model for spatial diffusion reflection with two-point-source δ-P1 approximation to the radiative transport equation for a semi-infinite homogeneous turbid medium,the optical absorption coefficient μa,reduced scattering coefficient μ＇ s,and the second-order parameter γ of the medium are recovered from the measurement data of the reflectance by the nonlinear least squares method.The results show that the two-point-source δ-P1 approximation can give more satisfactory results for describing irradiance distribution close to source when the source-detector separation is larger than one transport mean free path.We can also obtain the anisotropy factor g according to the relationship between γ and μ＇ s.This study is of great significance for the measurement of the optical properties of biological tissues and the application of diffuse reflectance spectroscopy technology.

关 键 词：组织光学 δ-P1近似 光学参量 双点源 

分 类 号：Q63[生物学—生物物理学]