大行程亚微米级精密定位系统的研究

针对荫罩式等离子体显示器屏板定位的特点，研究了基于计算机视觉的图像定位和基于衍射光栅的叠栅定位两种方法，利用这两种定位方法，建立了精密定位的复合控制系统，其中图像定位作为粗定位，光栅定位作为精定位。通过粗定位与精定位相结合的两段式复合定位，可保证在较大的工作行程范围内，实现显示器屏板的高速高精度定位，有效解决了定位精度、定位速度与信号捕捉范围三者之间的矛盾。系统采用的快速图像边缘检测技术、特征图形标识识别技术、精密光栅检测技术和精密驱动控制技术，确保了较高的定位精度及工作可靠性。实验结果表明，采用复合式精密定位可在50 mm的工作行程内获得±0.15 μm的屏板定位精度。

Research on the Long Range Precision Alignment System with Sub-Micron Accuracy

In view of the features of panel position of shadow-mask plasma display pare (SMPDP), two methods of precision positioning are brought forward: image positioning method and grating positioning method. The compound control system for precision positioning is set up using two kinds of the positioning technique, in which the image positioning method is used as the coarse alignment and the grating positioning method is used as the fine alignment. By using the two-step alignment, the high alignment accuracy and quick alignment speed are obtained in the big long positioning range. The algorithms such as fast image edge detection, character extraction, precision gratings detection and precise driving strategy are adopted to effectively improve positioning accuracy and reliability of the device. The experimental result shows the two-step alignment can perform positioning accuracy of ±0.15 μm in the working range of 50 mm.