Advances in real-time holographic interferometry for the measurement of vibrations and deformations

We describe the latest improvements in holographic interferometry that enable the real-time measurement of vibrational modes and static deformations in surfaces using low power laser illumination and a photorefractive Bi 12 TiO 20 crystal as the recording medium. An efficient setup has been developed where the most critical elements have been optimized: target illumination and backscattered light collection, distribution of light between the object and reference beams, and stabilized system operation. Experimental results for vibration and deformation measurements are reported.