Application of the CO2 Laser to Thermal Properties Measurements in Biomaterials

Abstract

The CO2 laser provides radiation that is strongly absorbed and only weakly back-scattered by high water-content materials, such as biological tissue. Several methods can be employed to obtain radial distributions of laser irradiance that are described by simple mathematical functions. It is therefore possible to use the CO2 laser to noninvasively establish an accurately known surface heat source. An effective thermal conductivity of the material can be determined from the temperature response due to laser heating. Thermal conductivity is reported for agar gel using CO2 laser heating and thermocouple temperature sensing.