Multi-layered model for simulating the <i>in vivo</i> terahertz response of human skin

Quantitative methods of evaluating the state of skin are highly beneficial for both diagnosis and treatment monitoring. The development of such methods relies on understanding how changes in skin properties affect the quantitative response. Effective modelling is often a crucial step in building this understanding. This work introduces a multi-layered model for simulating the <i>in vivo</i> terahertz response of skin, demonstrating how variations in skin properties may alter the measured signal. Furthermore, we hypothesise that the observed attenuation in the terahertz signal during an <i>in vivo</i> measurement is primarily a result of skin deformation and flattening under compression by the imaging window. Finally, we fit our model to measured data and extract optimised values for a skin deformation parameter.