Abstract
Non-contact techniques for the analysis of deformations on surfaces has had great boom and acceptance in various sectors of science. When a beam of light with characteristics of temporal and spatial coherence radiates about optically rough surface, it presents a random distribution of intensity, giving rise to the phenomenon called speckle; said phenomenon is a representation of bright and dark dots formed by the random distribution of said coherent light, this distribution of overlapping speckle patterns generate interference fringes, its fringes are presented when in second pattern fringes has phase difference between them, which, give information about the state of deformation suffered by the material that is analyzed. This work reports the procedure that is followed for the analysis of deformations in materials using interferometric techniques. Different configurations of interference fringes are presented, and the procedure for their demodulation is described.