Study Of Digital Speckle Correlation Method

Digital Speckle Correlation Method (DSCM) is a measurement technique which is developing rapidly today, and it has a great value in research due to its prominent advantages and extensive use. This thesis expounds the development process, principle, characteristics, classification, and application, etc. of DSCM, and also states the measuring methods and technical characteristics of digital speckle correlation method in spatial domain and frequency domain. The paper mainly studies the application of digital speckle correlation method in frequency domain, and designs an experiment to measure the in-plane micro-displacement.Vander-Lugt correlator was selected for experiment after it was compared with the results from joint transform correlator. The experiment errors had declined from less than4%to1%or less by using bilinear interpolation processing for the experiment results, which could significantly improve the measurement accuracy. The experimental results showed that it has obvious advantages such as simple structure, low environment requirements, rapid processing, and high accuracy, etc. when measuring in-plane micro-displacement by DSCM in frequency domain.