Passive introduction of carrier fringes in real-time photo refractive interferometers for single interferogram analysis

Abstract

We propose a new technique to introduce carrier fringes in an holographic interferometric setup for deformation or vibration analyses. This technique makes use of the anisotropic diffraction processes of photorefractive crystals. The main advantage of the proposed technique is that it just involves static components, no moving parts or active components are required. This technique is demonstrated in a real-time interferometric setup operating at the wavelength of 1.06 µm and with a GaAs photorefractive crystal as the holographic medium.

Multi-Channel Adaptive Interferometers Based on Dynamic Hologram Multiplexing

“…Another area of applications of phase demodulators based on photorefractive dynamic holograms is stabilization of fibre-optical interferometric sensors eliminating all unwanted influences of the environment (e.g., temperature changes) (Di Girolamo, et al, 2007a;Fomitchov, et al, 2002;Kamshilin, et al, 1995;Kamshilin, et al, 1998;Qiao, et al, 2006;Romashko, et al, 2005b). Adaptive interferometers find also application for real-time analysis of deformations and vibrations of technical constructions (such as space reflectors (Pauliat, et al, 2006) or even artworks (Thizy, et al, 2007)), for molecular recognition (Peng, et al, 2007), for acousto-optical imaging of biological tissues (Delaye, et al, 2005), for refractive index measurement (Lichtenberg, et al, 2005), in optical coherence-domain reflectometry systems (Peng, et al, 2003), and many others. Among those applications there is a class of practical problems where several simultaneous measurements are required (Kulchin, 2001;Peiponen, et al, 2009).…”