Photorefractive crystals for efficient linear sensing of speckle-pattern displacements

摘要

Abstract: Novel technique for the efficient remote sensing of speckle- pattern displacements is proposed. It is based on the polarization self-modulation effect recently discovered in photorefractive crystals. The technique provides linear responses on the amplitude of the lateral displacement and high sensitivity which is comparable with the interferometric one. Both sensitivity and dynamic range of measurements can be adjusted varying the average speckle size on the input face of crystal. The simple and inexpensive experimental set-up does not include any reference or read-out beam. Proposed technique can be applied for optical measurements of the transient motion of inspected surface such as object's vibration monitoring. !15