Polarization character of scattering light from tissue phantom

Polarization gating has been widely used to probe the structure of superficial biological tissue. However, the effect of the optical properties of tissue on the polarization state has not been well understood. Based on the model of detection system for Stokes vectors and Mie scattering theory, the distribution of scattering light intensity and degree of polarization (DOP) from two kinds of spherical particles with equivalent diameter of 5. 0 μm and 9. 0 μm were computed and analyzed by means of simulation. Thereafter, their backscattering DOP spectra were also calculated when they are illuminated with linear and circular polarization light. It is shown that single backscattering lights from both small and large particles have higher DOP, but their DOP spectra can sensitively reflect the change of their diameters. When linear polarization light is illuminated, both the oscillation frequency of spectra and the DOP increase with the particle size. It implies that the method has the potential significance for early cancer detection.