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n industrial application of structured light systems (SLS), besides the measurement accuracy, the robustness in long-time working situations is also significant. This requirement is hard to be satisfied due to the drifting of system parameters caused by factors such as the generated heat of the devices and the temperature variation of the environment. To ameliorate this drawback, this paper proposes a re-calibration method of SLS parameters in temperature-varying situations based on utilizing a series of circle marks as control-points. In this method, after initial calibration, a measurement of the whole workspace including these control-points is carried out as soon as possible, in which a series of two-directions phase images and an extra white image are captured. Through phase calculation and reconstruction, the precise poses of the control-points can be obtained and saved. Then, cost function is constructed by utilizing these control-points based on bundle adjustment and the system parameters are optimized. Compared with previous re-calibration methods, since extra constraint of relative pose between the camera and the projector is provided by registered circle marks, a target object with ground truth used to calculate the scale information in previous methods is not necessary anymore, which improves the compatibility of SLS application. Experiments are also carried out to verify the performance of this method.
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