An accurate three-dimensional scanning system with a new phase error compensation method

An accurate three-dimensional scanning system based on fringe projection and active triangulation is presented. The structured light projection is implemented by using a special grating element fabricated by electron beam lithography which ensures the phase-shifting accuracy and continuous intensity. The phase error caused by non-sinusoidal phase-shifting patterns is reduced significantly by a new compensation method, and an average 62.5% improvement of the vibration error is revealed. The experimental results indicate that the measurement error of the system is lower than 0.04 mm, with a variability of about 0.03 mm. The registration of multi-view test results indicates registration standard deviation can be lower than 0.1 mm. The system promises a favourable future for industrial application, especially in reverse engineering of free form surfaces.