Phase information extraction for moiré fringes based on multiresolution analysis

Abstract

In this paper, the multiresolution analysis (MRA) method is used to preprocess moiré fringes, which can reduce the number of data points and increase computation speeds. To discuss the applicability of the method, a candle combustion flow field is chosen as an example for experiment by moiré deflectometry. First, moiré fringes are preprocessed by the MRA method. Then, phase information extraction and refractive index reconstruction are performed on the three-level low-frequency approximation components. Finally, the involved results prove that the calculation time required for phase information extraction and refractive index reconstruction is greatly reduced based on the moiré fringes preprocessed by MRA method. The relative error could be accepted if the suitable approximation level is applied.