抄録
In the phase analysis, accuracy can
degrade when the intensity of bright and dark lines
in interference fringes varies significantly spatially,
or when the phase change Δφ is temporally
discontinuous. In this study, we improved the
interference fringe analysis method by focusing on
a local region in phase analysis and classifying
phase inter-frame differences δφ’ in phase
unwrapping. The objective of this study is to clarify
how to set the threshold for classifying δφ’ and the
accuracy of the phase φ and phase change Δφ obtained by the proposed method. Both experimentally
obtained in a microgravity and artificially generated interference fringes were analyzed using the
proposed method. As a result, the obtained spatial distribution of Δφ had a few outliers. In addition, it was
revealed that a reliable threshold for classifying δφ’ can be automatically determined by using the total
amount of tolerable noise and estimated δφ’. The phase error and the phase change error were as small as
0.025π and 0.034π rad, respectively, which is less than one-fifth of the conventional method.
