Interferometric flaw detection with an increased sensitivity of measurements in study of reflecting composite periodic structures

Methods that allow an interferometric comparison of the elementary structures of a reflecting composite periodic structure and a reference structure are described. Specific features of the realization of these methods by interferometric correlators are considered in the case of studying specular and diffusely reflecting composite structures with an increase in the sensitivity of measurements. Experimental results of testing these methods in application to the study of plane metal surfaces with cylindrical depressions are presented. Interference patterns with a twofold increase in the measurement sensitivity are obtained.