清晰显示高分辨率画面是LED显示屏图像质量提升领域中亟待解决的关键问题之一.针对LED显示屏分辨率低、成本高、像素排布灵活的特点, 研究了亚像素采样技术在LED显示屏中的应用.从信号处理的角度, 在RGB颜色空间中对LED显示屏建立了全像素采样和亚像素采样数学模型, 在亮度与色度相分离的空间中对两种采样方式进行了频谱分析, 证明了应用亚像素采样技术可以将显示系统的亮度混叠转移到了人眼较不敏感的颜色通道上, 有效扩展了LED显示系统在各方向上的Nyquist频率限制.物理屏体上的仿真实验表明亚像素采样对LED显示屏的图像显示质量具有改善作用.

Clear display of high-resolution pictures on LED displays is one of key problems to be solved in displaying quality improvement areas. Aiming at the features of LED displays, such as low-resolutions, high production costs and flexible in pixels arrangements,applications of sub-pixel sampling technique were analyzed. Firstly, the mathematical models of LED displays were set up from the information processing perspective. Then under theluminance and chrominance separated space such as YUV color space, by frequency analysis,it was demonstrated that aliasing in display images can be transferred from the luminance to the chrominance which was insensitive to human eyes.The Nyquist limits of them in all directions were effectively expanded. The simulation results on the real LEDdisplay further show the improvement of displaying quality by sub-pixel sampling.