Accurate calibration method for camera and projector in fringe patterns measurement system.

The 3D measurement system based on fringe patterns is widely applied in diverse fields. The measurement accuracy is mainly determined by camera and projector calibration accuracy. In the existing methods, the system is calibrated by a dot calibration board with traditional image process algorithms. In this paper, an improved calibration method is proposed to increase camera and projector calibration accuracy simultaneously. To this end, first, a subpixel edge detection method is proposed to improve the detection accuracy of reference features for coarse calibration; second, an iterative compensation algorithm is developed to improve the detection accuracy of the reference feature centers for fine calibration. The experimental results demonstrate that the proposed calibration method can improve the calibration accuracy and measurement accuracy.