Phase unwrapping method and system

Abstract

The embodiment of the invention provides a phase unwrapping method and system. The method includes the following steps: obtaining a truncation phase of a measured object according to structured light projected to the surface of the measured object; obtaining a reference plane through shooting and obtaining a reference plane unwrapping phase, and performing unwrapping operation according to the truncation phase and the reference plane unwrapping phase, thereby obtaining a first phase distribution result; building a virtual plane continuous phase, and performing unwrapping operation on the truncation phase and the virtual plane continuous phase, thereby obtaining a second phase distribution result; and performing phase region fusion on the first phase distribution result and the second phase distribution result, thereby obtaining an unwrapping phase of the measured object and a height distribution result. According to the phase unwrapping method provided by the invention, the virtual plane continuous phase is added to assist phase unwrapping, after multiple times of stage-by-stage phase unwrapping is performed, combined with a plurality of unwrapped phases, a final correct unwrapped phase is obtained, the unwrapping speed is fast and error propagation and diffusion are not easy to occur.

Description

Technical field [0001] The invention relates to the field of computer measurement and calculation, and in particular to a phase unwrapping method and system. Background technique [0002] In recent years, with the rapid development of computer technology, optics and optoelectronics technology, three-dimensional surface measurement of objects has important significance. Optical three-dimensional surface shape measurement methods based on phase analysis have been deeply studied and widely used because of their non-contact, fast measurement speed, and high accuracy. This type of method modulates the height distribution of the measured surface shape into the phase change of the projection light field, analyzes the obtained deformed fringe pattern, and calculates the corresponding phase distribution to reconstruct the three-dimensional surface shape distribution of the measured object. Since the phase distribution is obtained by the arctangent function operation, the calculated phase...

AI Technical Summary

Problems solved by technology

[0003] The traditional spatial phase unwrapping method is to search and locate the truncation point point by point according to a certain path in the two-dimensional space of the truncated phase for phase unwrapping, which is time-consuming, and some algorithms will cause "drawing"-like error propagation and accumulation on the unwrapped path; the time phase The unfolding method can avoid this type of error, but it needs to project and acquire multiple images with different fringe periods or mark the order of each fringe period, and use the relationship between periods or the encoding order to perform phase unwrapping on the time axis. The class method brings time consumption and complexity to both measurement and reconstruction

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