Development of temporal phase analysis techniques in optical measurement

Abstract

Temporal phase analysis techniques allow accurate measurements on non-static objects to be performed. In this thesis, different temporal phase analysis algorithms are studied. Based on two existing temporal phase analysis techniques, temporal Fourier analysis and phase scanning method, a new method is proposed in this study. It uses a robust mathematic tool i?? continuous wavelet transform as the processing algorithm. To demonstrate the validity of the proposed temporal phase analysis techniques, several experiments based on various optical techniques are designed. These include the profiling of surface with step change; velocity, displacement and shape measurement on continuous deformed objects; instantaneous displacement measurement on vibrating objects and displacement derivatives measurement. Compared to temporal Fourier transform, wavelet analysis calculates the optimum frequency at each instant, thus limits the influence of noise sources and increases the resolution of measurement significantly.