【作者】 常锋；

【导师】 王瑞光；

【作者基本信息】 中国科学院研究生院（长春光学精密机械与物理研究所） ， 电路与系统， 2011， 博士

【摘要】 本文针对目前LED显示屏灰度等级调制技术中存在的一些问题,开展了以下的研究内容:首先,介绍了LED显示屏灰度等级的调制原理和调制技术的发展现状;其次,针对现有技术的不足之处,通过构建时空混合叠加模型,提出了LED显示屏灰度等级时空混合叠加调制技术;然后,针对时空混合叠加模型存在的一些问题,对构建的时空混合叠加模型进行了优化;最后,用硬件描述语言VHDL实现了时空混合叠加调制技术,并且在实验平台上验证了这种技术。主要工作包括以下几个方面:1.构建了时空混合叠加模型。该模型按照一定方式把一个灰度等级调制过程分成了K (K = 2,4,8,16,…)个子调制过程,通过一系列的数学推导说明,与现有的灰度等级调制技术相比,构建的时空混合叠加模型可以在相同的视觉刷新频率下将LED显示屏的灰度处理能力提升log2K-bit,也可以在同等的灰度处理能力下将LED显示屏的视觉刷新频率提高K倍。2.优化了时空混合叠加模型。为了克服时空混合叠加模型在处理低灰度等级时存在的缺陷,对时空混合叠加模型进行了优化。从优化条件、优化目标和优化途径三方面说明了的模型优化的方案。同时对优化方案进行了分类,并且给出了各种优化方案的具体实施实例,最终完成了对时空混合叠加模型的优化。3.实现和验证了时空混合叠加调制技术。根据构建的时空混合叠加模型及其优化方案,用硬件描述语言VHDL设计了一个时空混合叠加加法器以实现时空混合叠加调制技术。并且在由数据传输单元、控制单元、驱动单元和显示单元构成的实验平台上验证了这种技术。工程应用结果表明,时空混合叠加调制技术可以实现LED显示屏灰度等级的高效、可靠调制。与现有的灰度等级调制技术相比,对静态屏来说,它可以在视觉刷新频率不变的情况下,把LED显示屏的灰度处理能力提升3-bit;对1/8扫描屏来说,它可以在视觉刷新频率不变的情况下,把LED显示屏的灰度处理能力提升2-bit,或者在灰度处理能力不变的情况下,把LED显示屏的视觉刷新频率提高4倍。更多还原

【Abstract】 This dissertation carries out the following researches for the problems that appear in the current grayscale level modulation technologies: Firstly, the modulation principle and the development status of the current modulation technologies of the grayscale level in the LED display panel is introduced, and the two main modulation technologies are analyzed. Secondly, the time-space mix-superposition modulation theory of grayscale level is proposed by constructing a mixed time-space mix-superposition model. Thirdly, the proposed time-space mix-superposition model is optimized because it has some defects while dealing with low grayscale level. Finally, the time-space mix-superposition modulation technology is achieved in VHDL which is one of hardware description language, and verified in an experimental platform. The main works and achievements are as follows:1. The time-space mix-superposition model is constructed that a grayscale modulation process is divided into K （K = 2, 4, 8, 16,L） sub-modulation processes according to a certain way, and a series of mathematical derivation is used to illustrate that the grayscale processing capacity can be increased by log₂K-bit with the same visual refresh rate, or the visual refresh rate can be enhanced to K times with the same grayscale processing capacity.2. The time-space mix-superposition model is optimized in the dissertation to overcome the defects while dealing with low grayscale level. The model optimization program is described from the optimization conditions, the optimization goals and the optimization approaches. Additionally, the optimal means are introduced through specific examples. At the same time, t the optimization program is classified and the specific implementation of examples for various optimization programs is listed. Finally, the time-space mix-superposition model is optimized.3. The time-space mix-superposition modulation technology is implemented and verified. A time-space mix-superposition adder is designed in VHDL, and verified in an experimental platform which is combined with the data transmission unit, the control unit, the drive unit and the display unit.The time-space mix-superposition modulation technology has been applied in the projects, and the results show that this technology is able to achieve efficient and reliable modulation of grayscale level in LED display panel. Compared with the current grayscale level modulation technologies, for the state display unit, the grayscale processing capacity can be increased by 3-bit with the same visual refresh rate; for the 1/8 scanning display unit, the grayscale processing capacity can be increased by 2-bit with the same visual refresh rate, or the visual refresh rate is enhanced to 4 times with the same grayscale processing capacity.更多还原