Abstract:To solve the calibration problems in the dimension measurement based on linear-structure light such as high requirement of environment,complicate calibration procedure and so on,a calibration method based on the grid panel has been presented. Its main advantage is that,rather than a complicated calibration model and high precision auxiliary equipment,only a calibration plane with 2 mm width and height at measurement place is needed. With corner-detection, the calibration parameters based on a global world coordinate can calculated, the revising system error correction was completed,and finally the measurement system into the image coordinate system was merged. The calibration method has been applied in billet outline dimension measurement and the experimental data shows that the method has stronger robustness and feasibility with the error of 0.05 mm.