Digital Image Correlation combined with Electronic Speckle Pattern Interferometery for 3D Deformation Measurement in Small Samples

The small size of mesoand microelectromechanical systems (MEMS) devices presents several challenges for full-field deformation measurements. A hybrid system combining Digital Image Correlation (DIC) for in-plane deformation and Electronic Speckle Pattern Interferometry (ESPI) for out-of-plane deformation measurements has been developed for working with these small size scales. Measurement of the full-field 3D deformation is useful for material characterization including tensile and performance testing of the samples. The combination of the two techniques yields a 3D deformation field of the component under test. For this paper, simple tensile test specimens of 0.76 mm × 10 mm were deformed to create simultaneous in-plane and out-of-plane deformations. The experimental system will be described in detail with a discussion of the results. A comparison between ESPI and DIC results will be briefly discussed, and compared to a conventional point-to-point shadowgraph measurement.