Locations of geometric (e.g crack tip) and concentrated load (e.g. vicinity of the contact forces) represent critical places of engineering structures. The optical caustics method is one of the few experimental methods which provide applicable results in the such locations. This method was originally developed for crack-tip measurements of stress intensity factors and Jintegral on isotropic and anisotropic materials. Additionally, it was extended to contact problems where the size and shape of caustics on the screen are related to the amount and the intensity of loading forces. In this paper the caustics method is extended to the analysis of contact problems of anisotropic materials, which makes the caustics method comprehensively applicable to analysis of any high stress locations in a structure. Experiments were performed on carbon fiber reinforced composites, where the epoxy resin Araldit B was used as reference isotropic material. Comparison of the simulations of the optical effect and the experiments indicated that for anisotropic materials size and shape of caustic curve depend not only on the loading conditions but also on the mechanical material properties. In isotropic materials the shape of the caustics curve is unique for all materials and can be expressed by the epicycloids equation. On non-transparent materials, as most of the technical materials usually are, it is possible to record the caustic curve only by utilizing light reflected from the model surface. In this paper special attention was dedicated to forming the optical setup which gives a clear image of the recorded caustics curves. In order to measure curve characteristics on the recorded images, subroutines are written which serve to reduce subjective operator errors during the curve shape measurement. It is shown that method of caustics can be used for the measurement of critical loads which lead to material yielding, as well as loads that lead to failure of composite material. It has been proven by example that the method can be used to determine the transition border between plane and spatial stress conditions in the vicinity of contact forces. The guidelines are given for future research as well as the application of the caustics method for solving contact problems in construction.