LED显示图像的非均匀度校正改进方法

摘要

针对LED显示屏在拼接过程中会出现显示图像非均匀度过高的问题,基于对现有CCD校正技术的改进,提出了非均匀度校正改进方法--畸变校正法.首先,介绍了现有的基于CCD的非均匀度校正技术,同时,阐述了技术需要改进的原因.以模块拼接的IED显示屏为例,构建了畸变校正模型.该模型根据畸变模块位置和理想模块位置之间的非线性关系,修正LED显示屏各像素点的灰度值,实现非均匀度的校正.按照构造的模型,描述了畸变校正的实现步骤.最后,在一个分辨率为128 pixel×128 pixel,模块的像素中心间距为7.62 mm,一个模块内只有一个像素点的LED显示屏上实现了该方法.实验结果表明,采用这种改进的方法,可以将LED显示图像的非均匀度由采用基于CCD的校正技术校正后的8.9%降低到0.97%.%In order to resolve the problem that LED display panel may appear position distortion and cause the high nonuniformity of LED display images, an improved method called distortion correction was proposed on the basis of an existing correction technique namely the correction technique based on CCD. The correction technique based on CCD was introduced, then the reason that this technique needs to be improved was expounded. By taking a LED display panel which is spliced by modules for the example, the distortion correction model was constructed. This model modifies the gray value of every LED display panel's pixel to reduce the nonuniformity according to the nonlinear relationship between distortion and ideal module position, Furthermore, realization steps were described in accordance with the constructed model. Finally, the improved method was implemented in a LED display panel with a resolution of 128 pixel× 128 pixel, pixel center spacing in module of 7.62 mm, and the module containing only one pixel. Experimental results show that this method is able to reduce the nonuniformity of LED display images from 8.9％ obtained by the correction technique based on CCD to 0.97％.