In this paper, we describe a calibration method for 3D vision system using pattern projection.The calibration consists of two phases: offline calibration of the parameters of the pattern projector and on-line calibration of the varying intrinsic and extrinsic parameters of the camera. During the on-line recalibration, we do not need to calibrate the homographies of all the light stripe planes relative to the camera, but just need to calibrate those of the two or more arbitrary light planes. Then all of the other light stripe planes homographies relative to the camera image plane can be recovered based on the relation derived in this paper between the homographies of the light stripe planes and their transformations with respect to the world coordinate frame. By this method, we can easily implement recalibration of the 3D vision system with its pattern projection when the intrinsic and extrinsic parameters of the camera are changed.