We developed a 3D measurement system consists of a camera and a projector which can be calibrated easily at short times. In this system, the camera and the projector are calibrated in advance with Zhang's calibration method. The measurement procedure in this system is as follows. A calibrated camera and a calibrated projector are put in front of the calibration plane. Then the relative pose between the camera and the projector can be computed by projecting a number of light patterns from the projector onto the calibration plane and taking those images with the camera. And this system performs a 3D measurement with the gray code pattern projection. Since this system can be calibrated easily, this system does not need to be fixed exactly and the configuration of this system, which is the baseline and the measurement range, can be changed freely depending on the target and the purpose. This system can obtain a range data in a high accuracy of an error about 0.1% in spite of the
fact that this system can be calibrated easily.