The fringe orientation angle provides useful information for many fringe-pattern-processing techniques. From a single normalized fringe pattern (background suppressed and modulation normalized), the fringe orientation angle can be obtained by computing the irradiance gradient and performing a further arctangent computation. Because of the 180° ambiguity of the fringe direction, the orientation angle computed from the gradient of a single fringe pattern can be determined only modulo π. Recently, several studies have shown that a reliable determination of the fringe orientation angle modulo 2π is a key point for a robust demodulation of the phase from a single fringe pattern. We present an algorithm for the computation of the modulo 2π fringe orientation angle by unwrapping the orientation angle obtained from the gradient computation with a regularized phase tracking method. Simulated as well as experimental results are presented.
© 2002 Optical Society of America
(100.2650) Image processing : Fringe analysis
(100.2960) Image processing : Image analysis
(120.3180) Instrumentation, measurement, and metrology : Interferometry
(120.5050) Instrumentation, measurement, and metrology : Phase measurement
Juan Antonio Quiroga, Manuel Servin, and Francisco Cuevas, "Modulo 2π fringe orientation angle estimation by phase unwrapping with a regularized phase tracking algorithm," J. Opt. Soc. Am. A 19, 1524-1531 (2002)