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Micro-vibration measurement is used widely in the field of materials testing, finite element analysis of the vibration, dynamic analysis of mechanical systems, biomedical and other fields. At present, the measurement technology of vibration are mainly divided into three types:mechanical measurement techniques, electrical measurement techniques and optical measurement techniques. Optical measuring method,optical interferometry is the most common and used widely for high accuracy non-contact vibration measurement. Nonlinear optical interference of light interference measurement method,which utilizes nonlinear characteristics of photorefractive crystal materials, can achieve the vibration measurement of higher frequency, more micro displacement.In this paper, considering the theory and experiment, we studied photorefractive effect and two-wave coupling properties of the BSO crystal, photorefractive interference optical vibration system design and vibration signal acquisition and analysis are also added. We also introduced research background, applications, domestic and international developments on the topic and main work of the paper. Uitilizing optical interference model, two-wave mixing characteristics of BSO crystal under the high voltage electric field is discussed, and experimental verification is gived. At the same time, we dissect principle, optical design of the optical interference systems, and the experimental device, key parameters of optical system design are added. Comparing with the Polytec PDV100 that is made in German for vibration measurement, we analyzed the advantages and disadvantages of system we studied, and discussed the measurement result of two systems, that is very important to improve design and perfect photorefractive interference vibration system. At last, all the work above and emphases in the future are summarized.
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