Research On The Digital Spackle Pattern Interferometry System Based On Spatial Carrier Phase Shifting

Digital Speckle Pattern Interferometry (DSPI) is a non-destructive,whole-field, high-resolution technique for non-smooth surface measurement. Itcombines several high techniques, including laser, electronic, computer, digitalimage processing, precession testing and etc. It is used in aerospace industry,automotive industry and biomedical industry successfully. Phase-Shifting has beena inseparable part in a DSPI system as phase subdivision technique. However,temporal phase-shifting as general phase-shifting technique used in DSPI isinsufficient in dynamic measurement. This paper is based on the project sponsoredby the National Natural Science Foundation of China (NSFC). In the dissertation, aDSPI system based on spatial carrier phase-shifting used in dynamic measurementis investigated and established, and is compared with a DSPI system based ongeneral temporal phase-shifting experimentally. Another research focus on the keyimage processing algorithms used in DSPI interferogram, mainly about phase mapfiltering and phase map unwrapping. In additional, a DSPI software is designed tohelp achieve a successful measurement in this paper. It also provides a solidfoundation for the subsequent integral and practical system design.The main work of this dissertation is as follows:1According to DSPI system principle and the measured object characteristics,a dynamic testing DSPI system based on spatial carrier phase-shifting is established.This dynamic testing system is compared with general static testing DSPI systembased on temporal phase-shifting, and analyzes their advantages and disadvantages.2the key techniques of digital speckle pattern interferogram are investigated,mainly about the phase extraction with different phase-shifting technique, suitablephase map filtering and unwrapping algorithms.3Based on Visual Studio2010platform with MIL and OpenGL, a DSPIsoftware is designed and compiled in Windows using C++language. This softwaresupports spatial carrier phase-shifting and temporal phase-shifting simultaneously,and provides two different measurement mode: high spped dynamic testing andhigh precision static testing. It is realized from the acquisition, processing to thefinal data output of a series of processes.4Based on the experimental system and software, different suitablephase-shifting method is chosen to meet the characteristics of the each measuredobject, and the deformation of each measured object is calculated successfully.