Dynamic Photothermal And Thermoelastic Microscopies Described By Complex Finite Element Analysis

Photothermal and thermoelastic microscopes are nondestructive apparatus that generally work with lock-in detection. The related magnitude and phase images are obtained for one modulation frequency. These techniques, devoted to nondestructive evaluation, are suitable for inverse problems such as thermoelastic parameter reconstruction. But up to now the thermoelastic models have been limited to simple geometries or have encountered many problems with temporal sampling. In order to overcome these problems we develop a finite element analysis dynamic method, based upon complex analysis, that enables us to directly obtain both thermal and thermoelastic magnitude and phase fields. This method has been applied to thermoelastic microscopy and has shown very good agreement with experiments. (c) 2006 American Institute of Physics.