Optical-acoustic diagnostics of defects on the surface of solids

Participants of the surface acoustic waves scattering excited by means of optical-acoustic method on the crack which has trapezium form is investigated. It is shown that the form and amplitude of the scattered impulse of the surface acoustical wave is depended on the crack width and its locality relative to the ultrasonic source and receiver. Experimental investigation of the influence of the impulse-laser radiator on the form and amplitude of the ultrasonic signal excited under traveling laser spot of the rectangular form over the fatigues crack of micron dimensions has show good quality accordance with conducted theoretical investigations.