THERMAL-DIFFUSIVITY MEASUREMENTS BY INSTANTANEOUS PHASE PORTRAIT METHOD

A new method of ''instantaneous phase portrait'' was developed for mea surements of thermal diffusivity chi of thin films with high values of chi, such as diamond films. This method is based on the registration of the air layer refractive index spatial distribution by means of dou ble exposure holographic interferometry and the derivation of the ther mal diffusivity value chi from the spatial distribution. The values of thermal diffusivity for copper and steel foils measured by this techn ique coincide with the tabular ones. The method was also applied to me asure thermal diffusivity of thin diamond films. The measured values w ere in 2-3 cm(2) s(-1) range.