Research on System Uncertainty of Laser Tracker under Site MeasurementYU Jing-jing, LIMing, ZHANG Jing, CHENG Fang Shanghai University, Shanghai 200072, ChinaAbstract:The measurement system of laser tracker is presented and the system uncertainty is analysed in this paper, Based on the laser tracker LTD840, several experiments have been done and on evaluation method of system uncertainty in the real time measurement is proposed. The relative result of measurement is proved by the experiments.[著者文摘]