A Calibration Method Based on Multi-Linear Structured Light

摘要

The mathematical model is established for a vision system including a camera and a multi-linear structured light sensor. In the model, a novel calibration method is proposed to calibrate multi-linear structured light using a coplanar reference target. In order to calibrate all structured light planes, firstly the two of those should be calibrated according to points on the coplanar reference target in different positions. In the model, the camera coordinate is considered as a global world coordinate, and all local world coordinates are transformed to the camera coordinate, so that all points can be reconstructed in the camera coordinate. In this way, when a camera and a light sensor are fixed together as a vision system, the whole system can be moved freely and easily, which is useful in engineering applications. In addition, a new algorithm to calculate cross ratio is presented, which decreases amount of calculation and improves the calculation precision effectively. Compared to similar technologies, the model decreases the cost of calibration equipment, simplifies the calibration procedure and improves the calculation precision. Experimental results show its convenience and effectiveness.