Self-normalized photothermal techniques for thermal diffusivity measurements

Two self-normalized photothermal techniques, to carry out thermal diffusivity measurements of condensed phase materials, are presented. These simple methodologies involve linear fitting procedures of the signal amplitude and phase. 'These procedures lead to the elimination of the usual requirement for instrumental transfer-function normalization. The thermal diffusivities for two dental resins and two pure liquids are measured with these simple methodologies and very good agreement is found with values reported in the literature, where more involved analysis is usually required. (C) 2000 American Institute of Physics. [S0021-8979(00)08124-X].