Comparative electronic speckle pattern interferometry using adaptive holographic illumination

Abstract

The development of spatial light modulators enables the application of active holographic optical elements in electronic speckle pattern interferometry. In our work adaptive comparative measurement is done, where an optically reconstructed image of a recorded or simulated single or double exposure hologram is used for holographic illumination of another object. In this paper, we present experimental results of measuring the difference of two deformations using this technique. The displacement difference can also be obtained numerically, if the wavefront used as a coherent illuminating mask does not belong to an existing object. This type of interferometer can easily adapt to the change of measuring conditions.