Figure 2.

Flow of DOS method. First, the measured backscattered intensity is obtained from the tissue sample and from a reference with known optical properties, enabling acquisition of the calibrated diffuse reflectance R_d of the tissue. Then, a mathematical model is employed to obtain the tissue absorption and scattering coefficients from the diffuse reflectance, and mathematical representations of μ_a(λ) and μ_s(λ) are employed to extract tissue absorber concentrations c_i, scattering amplitude A, and scattering power b.