Laser light propagation in soft tissues is important because of the growing biomedical applications of lasers and the need
to optically characterize the biological media. Following previous developments of the group, we have developed low
cost models, Phantoms, of soft tissue. The process was developed in a clean room to avoid the medium contamination.
Each model was characterized by measuring the refractive index, and spectral reflectance and transmittance. To study
the laser light propagation, each model was illuminated with a clean beam of laser light, using sources such as He-Ne
(632nm) and DPSSL (473 nm). Laterally scattered light was imaged and these images were digitally processed. We
analyzed the intensity distribution of the scattered radiation in order to obtain details of the beam evolution in the
medium. Line profiles taken from the intensity distribution surface allow measuring the beam spread, and to find
expressions for the longitudinal (along the beam incident direction) and transversal (across the beam incident direction)
intensities distributions. From these behaviors, the radiation penetration depth and the total coefficient of extinction have
been determined. The multiple scattering effects were remarkable, especially for the low wavelength laser beam.