New set-up to measure the thermal diffusivity with an infrared camera

We present a new approach to measure the thermal diffusivity of materials. An infrared camera coupled with a "lock-in" system developed by CEDIP corporation detects the amplitude and the phase of the infrared emission on the surface of an heated sample. We show in this article that the thermal diffusivity can be calculated in all directions around the heating laser beam with the phase images more quickly than our conventional IR microscope system.