A Simple Instrument to Measure the Thermal Transport Properties of the Human Skin

The evaluation of the skin thermal properties is relevant for many applications ranging from clinical dermatology to cosmetology. We introduce a simple passive device, capable of rapidly measuring skin thermal parameters using transient surface temperature measurements. Thanks to the development of an analytic thermodynamic skin model, tissue thermal diffusivity can be extracted from experimental data. For validation purposes, the thermal response of the apparatus has been modelled using a layered finite-element 3D model of the skin in thermal contact with a metallic measuring tip. Simplified 1D analytical and semi-analytical models have also been developed with the intent of modelling the thermal properties of the skin surface. The simplified models can be used to fit the thermal response measured by the device and to extract the thermal diffusivity in real time.