Flash Method for the Remote Sensing of the Thermal Diffusivity and the Absorption Coefficient at the Excitation Wavelength of Thin Film Materials

A novel front-face flash-monitoring algorithm for remote sensing of the thermal diffusivity and the absorption coefficient at the excitation wavelength of thin film materials is preseInted. The method relies on the surface transient temperature vs. time curve initiated by a short-duration heating pulse that is followed by time iIntervals during which the temperature response depends sensitively on the absorption coefficient and thermal diffusivity. An analytical solution of the problem has been derived to solve the inverse heat-transfer problem and, by comparison with a numerical experiment, to check the accuracy of the proposed algorithm for obtaining the absorption coefficient at the excitation wavelength and thermal diffusivity. The uncertainty of the proposed method is better than 0.1%.