Analysis by speckle interferometry of the dependency of yield stress on residual stress

In-plane sensitive electronic speckle pattern interferometer using a diffractive holographic optical element

“…Speckle pattern interferometry using a photographic method was first reported by Archbold et al 1 and further developed by Butters and Leendertz. 2 Electronic speckle pattern interferometry has found many applications in nondestructive evaluation, 3,4 mechanical stress analysis, 5,6 and vibration analysis. 7,8 In electronic speckle pattern interferometry the surface of an object is illuminated by laser light producing a speckled object beam which interferes with a coherent reference beam.…”