A flexible and high precision calibration method for the structured light vision system

Calibration is the process of estimating the intrinsic and extrinsic parameters of the device. In the field of photogrammetry, structured light measurement system is one of the frequently used active vision measurement systems. The accuracy of the estimated parameters of the system determines the measurement results in the later experiments and applications. Traditional methods were often not easy to implement and time-consuming. In this paper, a flexible and accurate method for calibrating the structured light system and a hybrid pattern which takes both the advantages of time multiplexing method and spatial neighborhood method is proposed. To make full use of the available open source of the camera calibration toolbox, this method treats the projector as a virtual camera. By analyzing the projected patterns and establishing the relationship between the projector and the camera, the projector of the structured light system is able to “capture” images on its own and thus can be calibrated easily and accurately like the usual camera as well. The experimental results show that the intrinsic and extrinsic parameters of the structured light system were estimated with high precision.