Estimation of surface damages by optical method

This paper describes the methods and test equipment for laser detection of surface damages such as scratches, cracks and changes of component surface condition due to chemical reactions or abrasive deterioration. The mathematical model of damage recognition probability after reaching of energetic matching between probing signal and geometric parameters of examined surface area is constructed. An experimental estimation of crack angle, crack depth and position of crack symmetry plane influences to radiation intensity distribution in the light spot when the spot reflects from the surface. The advantages of usage of laser diods in compact control-measuring systems on basis of quadruple systems with quantum-well structures are demonstrated.