AMOLED显示屏非均匀亮度补偿技术研究

发布时间：2018-03-17 03:10

本文选题：发光二极管　切入点：阈值电压　出处：《电子科技大学》2016年硕士论文　论文类型：学位论文

【摘要】：有源矩阵有机发光二极管(AMOLED)具有响应速度快、工作电压低、自发光、广视角、可柔性弯曲、高对比度等特性,被应用于手机、显示器、移动设备等领域。在高图像显示画质应用上,AMOLED有2个主要缺点,第一个缺点是由像素电路里薄膜场效应晶体管(TFTs)的电学特性参数变化导致的像素亮度不一致问题;第二个缺点是由有机发光二极管(OLEDs)老化导致的图像烙印问题。传统的由2个TFTs和1个电容组成的像素驱动电路(简称2T1C电路)无法解决以上2个缺点,因此为了能够满足AMOLED显示屏的亮度均匀性要求而开展具有补偿阈值电压和迁移率退化及OLED老化功能的像素驱动电路研究具有重要的意义。首先,论文对AMOLED像素电路设计的共性问题做了研究,分析了现有的像素补偿电路的算法和缺陷,基于混合编程方式补偿原理提出了一种新型实时视频数据调节的外部像素补偿算法,该算法能够检测多晶硅薄膜场效应晶体管和有机发光二极管的电学参数,并通过调节视频数据来补偿由于TFT电学特性变化和OLED老化引起的亮度不一致。其次,论文基于新型实时视频数据调节的外部像素补偿算法搭建了全新实时视频数据调节的外部像素补偿电路。该实时视频数据调节的外部像素补偿电路由像素电路和数据驱动电路两部分组成。像素电路由5个P型TFTs,1个存储电容和1个OLED器件构成。数据驱动电路包含2个开关,1个用于检测迁移率的电流源,1个模拟-数字转换器(ADC),1个查找表(LUT),存储器,数据调节模块,1个数字—模拟转换器(DAC)和1个缓冲器。最后,论文对新型实时视频数据调节的外部像素补偿电路进行了建模和仿真验证。仿真结果表明亮度不一致率为3%,远低于2T1C像素电路的92.1%的亮度不一致率。
[Abstract]:Active Matrix Organic Light-emitting Diode (AMOLED) is used in mobile phones and displays because of its high response speed, low working voltage, self-luminescence, wide viewing angle, flexible bending and high contrast. In the application of high image quality, AMOLED has two main disadvantages. The first one is the inconsistency of pixel brightness caused by the change of electrical characteristic parameters of TFTs in the pixel circuit. The second drawback is the problem of image imprinting caused by the ageing of organic light-emitting diodes (OLEDs). The traditional pixel drive circuit consisting of two TFTs and one capacitor (2T1C circuit for short) cannot solve these two disadvantages. Therefore, in order to meet the requirement of brightness uniformity of AMOLED display screen, it is of great significance to study the pixel driver circuit with the function of compensating threshold voltage and mobility degradation and OLED aging. In this paper, the common problems in the design of AMOLED pixel circuits are studied, and the algorithms and defects of the existing pixel compensation circuits are analyzed. A new external pixel compensation algorithm for real-time video data regulation is proposed based on the mixed programming compensation principle. The algorithm can detect the electrical parameters of polycrystalline silicon thin film field-effect transistors and organic light-emitting diodes, and compensate for the inconsistency of brightness caused by the change of TFT electrical characteristics and the aging of OLED by adjusting the video data. Based on the new external pixel compensation algorithm for real-time video data adjustment, a novel external pixel compensation circuit for real-time video data adjustment is constructed in this paper. The external pixel compensation circuit for real-time video data adjustment consists of pixel circuit and external pixel compensation circuit. The pixel circuit consists of five P-type TFTs, one storage capacitor and one OLED device. The data drive circuit consists of two switches, a current source for detecting mobility, and an analog-to-digital conversion. A lookup table, a latch, a memory, Data adjustment module, 1 digital to analog converter DAC) and 1 buffer. Finally, In this paper, the external pixel compensation circuit for real-time video data regulation is modeled and simulated. The simulation results show that the luminance inconsistency rate is 3, which is much lower than the brightness inconsistency rate of 92.1% in 2T1C pixel circuit.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TN873.3

【相似文献】