There are different approaches to diffuse reflectance modeling, most of them based on the solution of the radiative transport equation by the diffusion-based approximation. However, a set of fiber optic probes measure only a part of the diffuse reflectance leaving the tissue surface, and therefore there is inherent scale invariance in the measurement.
Then, how could I consider the numerical aperture and the refractive index of the fibers to remove scale invariance in the measurements?