Deformation studies with BaTiO3 Crystal as a recording medium
12 Dec 1994-Vol. 2340, pp 40-49
TL;DR: In this paper, the optical characteristics of BaTiO3 crystal under the two configurations were discussed and used for speckle photography and image plane holography, where the phase shift of (Phi) between the dynamic grating and the interference pattern was shown to be +/- (pi) /2.
Abstract: Photorefractive crystals are gaining importance as a recording medium due to the possibility of real-time operations. A BaTiO3 crystal can be used as a recording medium in two configurations, i.e., when the phase shift of (Phi) between the dynamic grating and the interference pattern is (Phi) = +/- (pi) /2. The optical characteristics are different for the two configurations. We discuss the optical characteristics of BaTiO3 crystal under the two configurations, and use the BaTiO3 for speckle photography and image plane holography.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Citations
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TL;DR: In this article, a real-time visual approach for the calibration of phase step in image plane holography using BaTiO3 crystal as a recording medium is reported, where the diffuse object is illuminated symmetrically with two collimated beams and a pump beam is added at the crystal plane.
Abstract: A real-time visual approach for the calibration of phase step in image plane holography using BaTiO3 crystal as a recording medium is reported. In this method, the diffuse object is illuminated symmetrically with two collimated beams and a pump beam is added at the crystal plane. Each illuminating beam generates an individual interferogram at the observation plane when the object is subjected to load. A p phase shift to one of the illuminating beams results in the complete disappear- ance of the fringes due to phase reversal between the individual inter- ferograms, and at 2p phase change, the fringe pattern is restored. After calibration, a single-beam illumination configuration is used for phase measurement. We present the theory of the method and experimental results for a centrally loaded diaphragm rigidly clamped along the periph- ery. © 1998 Society of Photo-Optical Instrumentation Engineers. (S0091-3286(98)01611-0)
7 citations
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TL;DR: A two-beam coupling configuration using a BaTiO 3 crystal as recording medium for real-time displacement measurement of distant objects using a high coherent source such as frequency-doubled diode-pumped Nd-:YAG laser is presented in this article.
5 citations
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TL;DR: In this article, a two-beam illumination method, employing a BaTiO 3 crystal, was proposed for real-time displacement measurement and a single beam illumination method for realtime slope measurement.
Abstract: Photorefractive crystals have gained importance as a recording medium due to the possibility of real-time operations. Various real-time holographic and interferometric techniques have recently been proposed, exploiting salient features of different photorefractive crystals. In this paper we propose and demonstrate a two-beam illumination method, employing a BaTiO 3 crystal, for real-time displacement measurement and a single beam illumination method for real-time slope measurement.
2 citations
References
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TL;DR: In this paper, two-beam coupling in BaTiO 3 crystal is suggested for the tracking novelty filtering in speckle metrology and two schemes are discussed: one for point measurement of displacement and another for full-field display.
21 citations
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TL;DR: A holographic technique is developed which allows one to obtain in real time the contour map of an arbitrarily shaped object and suffers from a breakdown in its functioning due to a saturation of the phase carrying capacity of the interferometer.
Abstract: A holographic technique is developed which allows one to obtain in real time the contour map of an arbitrarily shaped object. The method provides a relatively coarse contouring of the object. While still operating at low sensitivities, the method suffers from a breakdown in its functioning due to a saturation of the phase carrying capacity of the interferometer. As a consequence, a phase management strategy is introduced, whose incorporation to the technique enables a substantial improvement of its performance. These developments are systematically analyzed and presented. The method is whole field and noncontacting. The live and flexible character of the method enables one to rapidly generate sensitivities tuned to the relief variations of objects of broadly varying depths. Experimental results are presented to illustrate the feasibility of the proposals.
20 citations