A simple method for phase wraps elimination or reduction in spatial fringe patterns

作者：Qudeisat Mohammed; Gdeisat Munther^*; Burton David; Lilley Francis

来源：Optics Communications, 2011, 284(21): 5105-5109.

DOI：10.1016/j.optcom.2011.07.024

• Phase stepping
• Phase unwrapping
• Fringe pattern analysis

In this paper, we propose a simple method for processing a 2D wrapped phase map that contains a spatial carrier signal in order to completely eliminate, or greatly reduce, the number of phase wraps in the image. The 2D Fourier transform of the wrapped phase map is calculated. Then the spectrum is shifted to the origin in frequency space. After that, the inverse 2D Fourier transform is computed. Finally, a four-quadrant arctangent function is used to calculate the angle of the complex array that was produced by the inverse 2D Fourier transform. This produces a phase map with a smaller number of 2 pi phase jumps than the original phase map. In some cases, all of the phase wraps are eliminated and there is therefore no need to unwrap the resultant phase map. The reduction of the number of 2 pi phase jumps can reduce the execution time and improve the noise performance of some phase unwrapping algorithms such as the Flynn method. The validation of the proposed algorithm is demonstrated experimentally and also via computer-simulation.

• 出版日期2011-10-1