散射相函数的高阶光学参量研究

发布时间：2018-04-06 20:30

本文选题：高阶光学参量　切入点：散射相函数　出处：《光散射学报》2017年03期

【摘要】：漫反射光谱技术被广泛应用于无创测量生物组织光学性质。当光源与探测器很近时,仅仅依靠吸收系数μ_a和约化散射系数μ′_s不能准确描述光源附近光的传播状态。而二阶光学参量γ的引入改善了近光源光的传播状态的描述。本文将生物组织的散射等效成特定球形颗粒的散射,基于Mie散射理论,计算了与散射相函数p(θ)有关的单粒子和多分散系粒子的二阶光学参量γ,研究了γ随尺度参数α和相对折射率m的变化规律,描述了γ与组织结构参量之间的联系,并阐述了γ对粒子特征的表征能力。研究表明,参量γ对尺度参数α小于2的微粒尺寸的改变是敏感的,并呈二次函数关系,其系数与相对折射率呈线性关系;对于相对折射率和尺度参数都不相同的两个粒子,他们的各向异性因子g相同时,二阶光学参量γ却不同,粒子越大,γ表征粒子特征的能力越强。这对于无创探究组织微观形态具有深远的意义。
[Abstract]:Diffuse reflectance spectroscopy is widely used in noninvasive measurement of optical properties of biological tissues.When the light source is close to the detector, the light propagating state near the light source can not be accurately described by merely relying on the absorption coefficient 渭 _ a and the reduced scattering coefficient 渭 _ s.The introduction of the second-order optical parameter 纬 improves the description of the propagation state of the near-light source.In this paper, the scattering of biological tissue is equivalent to that of a specific spherical particle. Based on the Mie scattering theory,The second order optical parameter 纬 of single particle and polydisperse particle related to scattering phase function p (胃) is calculated. The variation of 纬 with the scale parameter 伪 and relative refractive index m is studied, and the relation between 纬 and structure parameters is described.The characterization ability of 纬 to particle characteristics was also described.The results show that the parameter 纬 is sensitive to the change of particle size when the scale parameter 伪 is less than 2, and its coefficient is linearly related to the relative refractive index, and for two particles with different relative refractive index and scale parameter,When their anisotropy factor g is the same, the second order optical parameter 纬 is different, and the larger the particle is, the stronger the ability of 纬 to characterize the particle is.This is of great significance for non-invasive inquiry into the micro-morphology of organizations.
【作者单位】：天津大学理学院光电信息技术科学教育部重点实验室;
【基金】：国家自然科学基金(60278004)资助
【分类号】：O436.2

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