The method of three-step elecnronic speckle pattern interferometry (ESPI) with arbitrary phase shifts of a reference wave is proposed. This method does not require the calibrated phase shif¬ting techniques, which are necessary for recording speckle interferograms (SI) with fixed phase shifts by conventional temporal ESPI methods. In contrast to the two-step ESPI method with blind phase shift of a reference wave, the proposed three-step method does not use the time consuming procedure of the reference and object wave intensity distribution recording. So, to retrieve the phase map of surface displacements, this method uses only three SI before applying the load to the studied specimen and three SI after applying the load. The proposed method is faster than aforementioned two-step method, because the integrating bucket approach can be used for its realization.

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