Analytical Sciences vol:17 Special Iss. SI pages:S406-S409
Effects of lateral heat flow on photothermal spectra and the repercussions on photothermal depth profiling are investigated. Thermal conductivity depth profile reconstructions of case hardened steel samples are obtained by a neural network method which takes into account the photothermal spectral information and the pump beam characteristics. The feasibility of the method is illustrated for simulations. The method is also applied on experimental data obtained in conditions with substantial influence of three dimensional heat flow due to a finite excitation laser beam beam diameter.