A spherical fractal model is introduced to calculate the scattering coefficient, anisotropy factor and scatterring phase function. Double contour lines of the scattering coefficient and anisotropy factor are used to invert the fractal dimension and relative refractive index. Numerical results show that scattering coefficient decreases in the form of power function as the wavelength increases in the visible optical band; the anisotropy factor is nearly indepent of wavelength and its magnitude is inversely proportional to the product of fractal dimension and relative refractive index; the phase function based on the spherical fractal model agrees with the Henyey-Greenstein phase function in the forward direction (I. E. The scattering angle < 100°) and has the more accuracy in the backward direction.%建立了生物组织的球状分形结构模型,对生物组织的散射系数、各向异性因子、散射相函数进行了数值计算,提出了利用散射系数和各项异性因子的双等高线反演分形维数和相对折射率的方法.计算结果表明:在可见光波段生物组织的散射系数随波长的增加呈现幂函数衰减的关系；各向异性因子几乎与波长无关,在数值上与分形维数和相对折射率大小成反比.基于球状分形结构模型的散射相函数与Henyey-Greenstein (HG)相函数在前向(散射角＜ 100°)具有良好的一致性,同时较好的弥补了 Hc相函数在后向表征上的不足.
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