激光成像仪器中的行、场扫描同步控制

Synchronization control for row and column movement on laser imaging instruments

为了提高光点的位置精度,从而提高成像质量,提出了一种基于PWM控制的双光栅反馈的控制方案。基于数字PID原理,利用微处理器和H桥组件LMD18200,构建了全数字化的双芯片同步系统,实现了水平光学扫描和由直流力矩电机驱动的垂直扫描的同步控制。该系统结构简单,控制参数完全由软件设定,调整方便。自检方格测试结果证明,相对于开环步进电机驱动方法,同步控制精度从±50μm提高到±20μm。

To improve dot position accuracy and image quality, a PWM control system with raster feedback on the basis of digital PID was developed. The whole control system was composed in one single-chip computer and a H-bridge LMD18200. The synchronization control was realized by introducing row optical scan and column torque DC motor driven system. This system is of simple in structure, and control parameters are all determined by software and easily adjusted. The experiment of self-evaluation shows that the synchronization accuracy can attain ±20μm compared to ±50μm of the open-loop step motor driven system.