Biological Tissue Equivalent Scattering Particle Model Of Light Transmission

As the optics technology is widely used in biomedicine, a new crossing discipline named tissue optics has shaped. How to describe the process of the light propagating in tissue hasn't been well resolved. Some taste research on this problem is carried out for the purpose of giving more accurate guidance in biomedicine.Based on the character of tissue structure, equivalent scattering particle model is presented during the study which is used to describe the scattering in tissue. We take the scatters in tissue as spherical or ellipsoidal particles with different sizes and optical property. And the scattering property of the equivalent scattering particle is discussed with Mie theory. Compared with the models in existence, it takes more consideration of the influence caused by the difference in size and optical properties of scatters. After a great deal of computation, the Mie phase functions of the single particle or polydisperse particles are given here in numerical expression. These functions provide a sound explanation for the experimental phenomena about the increase of backscattering light from tissue, which can't be well explained by HG phase function.Light propagation in lamb tissue is simulated furthermore by Monte Carlo method basing on the equivalent scattering particle model. And the influence of the scattering coefficient, absorption coefficient and size of scatters in tissue on propagation of light in tissue is studied in detail. In addition, the research on the theory about the polarization change during the process of light propagating in tissue is done here. And with Monte Carlo algorithm the propagation of light is simulated when the nature and left circularly polarized light incident in tissue.The results show that simulation with Monte Carlo method basing on the equivalent scattering particle model can not only describe the energy distribution during the propagation of light in tissue, but also provide an effect theory tool to deal with the polarization when the light transports in tissue. The study may benefit the perfecting the theory about light propagation in tissue.