激光直写系统中DMD控制方法的设计与改进

Design and Improvement of DMD Control Methods in Direct Laser Writing System

为解决在激光直写系统中利用数字微镜器件(DMD)无法对纵向像素数大于768的灰度图像进行滚动显示的问题,文章在其控制电路的数据传输、存储及显示驱动技术方面开展了研究。利用FPGA中丰富的逻辑资源实现了图像数据传输方式的改进,通过移位寄存器对数据进行拆分和位宽转换。提出间隔存储方法实现大尺寸灰度图像数据的存储,基于此方法可实现灰度图像滚动显示时的数据读取。同时,省去在上位机中进行位平面拆分和图像分割的预处理步骤,简化了上位机操作流程并提高了系统数据传输效率。实验结果表明,该系统能够以419.6Hz的刷新率对大尺寸灰度图像进行滚动显示。

In order to solve the problems of scrolling grayscale images of a vertical pixel count higher than 768 using digital micromirror device(DMD)in direct laser writing system,the data transmission and storage and display driving technology of the control circuit was studied.The improvement in image data transmission mode was realized based on the rich logic resources in the FPGA which were used to split the data and convert the bit-width through shift registers.In addition,an interval storage method was proposed to realize the storage of large-size image data.Based on this method,the data can be read during the scrolling display of grayscale images.The workflow of the DMD display device was simplified and the efficiency was promoted by saving the operations of bit-plane splits and images segment in the upper computer.The experimental results show that the system can complete the scrolling display of grayscale image with 419.6 Hz.