Investigation Of Microvibration Detection Using Interference Of Nonlinear Optics

The importance of vibration detection in industrial production and science investigation has been accepted widely, and the measurement of vibration has become the significant research problem in engineering technology. Recently, with the rapid development of micro-electro-mechanical technology and precision machining technology and many important applications, small displacement and small vibration related with objects are interested by academia and industry. Optical detection is a non-touch and scatheless measurement technology, it also has the advantage of simple structure, high accuracy and perfect stability, so it is always in the guiding position in metering. In optical detection meathods, interferometry is most used widely and the meathod using photorefractive crystal is a novel technique.In this paper, the characters of the photorefractive crystals are studied, including the principle of photorefractive effect,two-wave mixing and four-wave mixing. Photorefractive effect is the base of two-wave mixing. The research in this chapter provides substantial theories for the microvibration detection using interference of nonlinear optics.Further more, the method of microvibration detection by optical interferometry is investigated, the scheme is presented to dispose the result of the detection of displacement and frequency, the effects of microvibration detection by optical interferometry are investigated experimentally.At last, all the works above are summarized and the emphases in future investigation are also put forward.