Simultaneous 3D digital holographic interferometry for strain measurements validated with FEM

This work introduces a digital holographic interferometer in a simultaneous 3D configuration to detect superficial strains. The system uses a single monochrome sensor and three different lasers in a two exposure method, which can successfully measure the superficial deformation during a controlled deformation. An aluminum plate with a well-known geometry is used as a proof of principle. The deformation and all physical variables are simulated with a finite element algorithm. The comparison between the experimental and the simulated results helps to validate the system's measurements with very good agreement. A description of the technique is presented.