由于人类视觉系统感知的亮度与显示器实际显示的亮度为非线性关系, 需要对显示器的视频数据进行伽马校正, 使显示亮度适应人眼的感知需求。本文提出一种针对硅基OLED微型显示器的伽马校正方法。首先, 基于人眼视觉的伽马特性, 分析伽马校正的基本原理。然后, 提出对输入视频数据进行位宽拓展达到非线性输出, 并基于查找表和分段可调的线性差值算法实现伽马校正。最后, 根据实际XGA039芯片发光情况调试校正参数以达到更优的显示效果。实验结果表明: XGA039芯片最大发光亮度为20 000 cd/m2, 在伽马取值为2.2时, 采用可调非均匀分段获得了较好的显示效果。所提出的伽马校正方法能够使视频图像的显示质量明显改进, 且较传统方式在精度和实现面积上均有一定优势。

Since the perceived brightness of human visual system is nonlinear with the actual displayed brightness of the display, gamma correction for the video data of the display is required to adapt the display brightness to the needs of the human eye. This paper presents a gamma correction method for a silicon-based OLED micro-display. Firstly, based on the gamma characteristics of the human visual system, the basic principles of gamma correction are analyzed. Then, the bit width extension for the input video data is proposed to achieve the nonlinear output, and the gamma correction is implemented based on look-up table and segment-adjustable linear difference algorithm. Finally, the correction parameters are adjusted according to the actual XGA039 chip’s illumination. The experimental results show that the maximum luminance of the XGA039 chip is 20 000 cd/m2, and better display effect is obtained when the gamma value is 2.2 and the adjustable non-uniform segmentation is used. The proposed gamma correction method can significantly improve the display quality, and has certain advantages in accuracy and implementation area compared with the conventional methods.