title: Application of the radial basis function interpolation to phase extraction from a single electronic speckle pattern interferometric fringe.
abstract: In this paper, we introduce the radial basis function (RBF) interpolation method to electronic speckle pattern interferometry (ESPI) and propose the RBF interpolation method to obtain unwrapped phase values based on a skeleton map. Because of the excellent approximation properties of the RBF interpolation, the proposed method can extract accurate phase values from a single fringe pattern effectively, even using a simple 3×3 mean filter as preprocessing. Using our method, both special filtering methods for ESPI fringes as preprocessing and postprocessing, including a dilatation and erosion algorithm for pruning and connecting and the smooth algorithm for improving the phase values are not needed. We test our method on a computer-simulated and two experimentally obtained poor-quality fringe patterns. The results have demonstrated that our RBF interpolation method works well even under a seriously disconnected skeleton map where it is impossible to apply the widely used, Matlab function grid data interpolation or the backpropagation neural networks method [Appl. Opt. 46, 7475 (2007)].
authors: Science and Technology on Electronic Test & Measurement Laboratory, North University of China, 030051 Taiyuan City, Shanxi, China. tygaowang@163.com
authors: Gao
authors: G
authors: Wang
authors: Yang Jun
authors: YJ
authors: Li
authors: Han Chang
authors: HC
authors: Zhou