Thermal wave methods: some experimental pitfalls

Uncertainties in the spatial distributions calculated from thermal wave data are normally attributed to the ill-posed deconvolution problem. This paper focusses on the impact of "ill-posed" experimental conditions on the pyroelectric spectra. The spectra are affected by structural inhomogeneities and temporal changes in the electrical and thermal properties, by distortions caused by the electric circuit, by frequency-dependent properties and by piezoelectricity. Experimental results are given for PVDF and LiTaO/sub 3/. Suggestions are made to reduce the effect of experimental errors.