In this work, we proposed a procedure for the calibration of 3D surface shape measurement system, which is based on fringe projection and phase shifting algorithms. Our approach consists in the use of temporal phase unwrapping methods to determine the phase-to-height mapping relationship. In particular, we propose the use of the two-step temporal phase-unwrapping algorithm. For that, two sequences of fringe patterns (low and high sensitivity) are projected onto the reference plane, which is shifted perpendicularly to the camera-projector plane. Then, the phase maps at each shifting step are retrieved from acquired sequences of sinusoidal intensity patterns using the two-step temporal unwrapping formula. Finally, using the phase maps at well-known in a least-squares scheme, the system parameters, nonlinear model of calibration, are estimated, i.e. the phase-to-height mapping relationship. Validation experiments are presented.
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