| Digital speckle correlation method (DSCM) is an optical measuring technique, which was developed in the 80's of last century. The important meaning of DSCM research is that it possesses many advantages, such as white light source, simple optical arrangements, big measuring range and no requirement of vibration isolation, of which other traditional optical measuring methods are lack. Unfortunately the existing DSCM is not so perfect to be used in engineering measurement not only on precision but on processing speed. For example, the displacement and strain measurement accuracy is low due to the influence of noise or the imperfection of the algorithm and the deformation rule and phenomena cannot be displayed. In addition, on 3D displacement measurements only a few works have been done. In this paper, some key techniques for 2D and 3D measurement using DSCM are studied, and a new DSCM software measurement system is developed, which satisfies the requirements of engineering measurements and provides the best tools for further application.The main achievements of this thesis are listed as following: (1) A new 2D digital speckle correlation method (DSCM-2D) based on the gray gradient iteration algorithm and a smoothing technique based on finite element and 2D generalized cross validation (2D GCV) are developed, which completes the smoothing of displacement data and noise reduction. Both the simulated and actual speckle experimental results reveal that this new method can obtain high displacement measurement accuracy even under high noise and complicated conditions and it can satisfy different measuring requirements. (2) A new 3D digital speckle correlation method (DSCM-3D) based on the small plane assumption and camera model is developed, which resolves the matching problem of the reconstruction 3D space coordinate from image coordinate in binocular vision. Combining both DSCM-2D and DSCM-3D techniques, the calculation of 3D space displacement is realized and...
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