基于蒙特卡罗方法的LED芯片定位系统误差分析

Error Analysis of LED Chip Positioning System Based on Monte Carlo Method

该文根据LED芯片定位系统的特点,构建了从图像坐标系到芯片坐标系的数学模型。检测运动控制、图像处理过程以及标定过程中的误差分布,通过蒙特卡罗分析法估计LED芯片的定位误差,计算了各个测量变量对最终定位误差的敏感度。分析结果表明,绕z轴旋转角度误差为LED芯片定位系统误差的主要来源,图像处理误差以及运动控制误差对系统误差影响较小。因此,通过标定算法补偿绕z轴旋转角度误差是提高LED芯片定位精度的关键。

Based on the characteristics of the LED chip positioning system, a mathematical model from the image coordinate system to the chip coordinate system is established in this paper. The error distributions of motion control, image processing and calibration process have been measured. The positioning error of LED chip is estimated by Monte Carlo analysis method, and the sensitivity of each measurement variable to the final positioning error.is calculated. The analysis results show that the main error source in the LED chip positioning system is resulted from the angular error around the z axis, while the image processing error and motion control error have less influence on the system error. Therefore, compensating the rotation angle error around the z axis by the calibration algorithm is the key to improve the positioning accuracy of the LED chip.