Investigation of crack origin in hybrid components with twocolor digital Fresnel holography

The paper presents a two-color digital holographic interferometer. The set-up is devoted to the investigation of crack origin in hybrid industrial electronic components. Optical configuration and algorithms to recover the optical phase of two-color digitally encoded holograms are described. The method is based on a spatial-color-multiplexing scheme in which holographic reconstruction is performed using a spectral scanning algorithm. Experimental results exhibit in-plane and out-of-plane non uniform deformations that are the probable cause of the cracking of the component.