In this work an overall view of the thermal diffusivity measurements i
n anisotropic materials using photothermal methods is presented. First
we study the case of anisotropic materials whose principal axes are a
t the surface. Then anisotropic specimens with buried principal axes a
re analyzed. Finally, we explore the possibility to extend our results
to the case of anisotropic and heterogeneous materials, such as carbo
n fibre reinforced composites.