In-plane micro-displacement measurement based on digital speckle correlation method in frequency domain

When using traditional digital speckle correlation method to measure in -place micro - displacement, the noise and algorithm defects will cause low accuracy or slow data processing. In order to solve these problems, digital speckle correlation method in frequency domain is applied. In-plane micro-displacement measurement has been realized by speckle recording and MATLAB software programming. This method is not only making up for the inadequacies of traditional digital speckle correlation method but also simplifying the repeated adjustment in general optical measurement. Theoretical analysis and experimental results show that digital speckle correlation method in frequency domain for measuring in-plane micro-displacement has many advantages: simple system construction, fast measurement and high accuracy, the measure accuracy can be up to micro level and relative error less than 1%.