Thermal imaging of a heat transport in regions structured by femtosecond laser

A non-contact determination of thermal diffusivity and spatial distribution of temperature on tens-of-micrometers scale is demonstrated by thermal imaging. Temperature localization and a heat flow have been in situ monitored with similar to 10 ms temporal resolution in Kapton polymer films structured by femtosecond laser pulses. The structured regions can localize temperature and create strong thermal gradients of few degrees over tens-of-micrometers (similar to 0.1 K/mu m). This is used to induce an anisotropy in a heat transport. Temperature changes on the order of similar to 0.1. degrees C were reliably detected and spatial spreading by diffusion was monitored using Fourier analysis. Application potential, miniaturization prospects, and emissivity changes induced by laser structuring of materials are discussed. (C) 2011 Optical Society of America