Optical parameter measurements by collimated light transmission

Some medical applications involving the interaction between light and biological tissues require both the knowledge of optical characteristics of tissues and a realistic treatment of light transport into them. In this work we describe a transillumination technique testing water solutions of Intralipid by the transmitted radiation intensity. The experimental apparatus includes a diode laser ((lambda) emiss equals 820 nm), a detection fiber, a PMT and a Digital Signal Analyzer. The performances of this very simple and cheap system are comparable to those ones obtained with more sophisticated apparatus; the results show that this technique could represent a preliminary step toward the realization of an user-friendly and cheap laser system for measuring optical parameters of tissues.