碳纳米管FED驱动系统的研究

【作者】 宗耿；

【导师】 张晓兵； 雷威；

【作者基本信息】 东南大学 ， 物理电子学， 2005， 硕士

【摘要】 场发射显示器(field emission display，简称FED)是一种近年发展起来的阴极射线荧光显示装置，属于薄板平面显示器，以碳纳米管作为场发射冷阴极的FED成为目前研究的热点。其驱动电路不仅技术含量很高，而且在整机成本中所占的比例也很大。本论文首先介绍了平板显示器和传统的CRT显示器在结构上的不同，其像素的构成和相应的驱动方式都存在着很大的差异。作为平板显示器的一种，碳纳米管FED采用矩阵扫描的方式实现动态显示，并采用电压脉宽调制的方法实现其灰度。整个驱动系统由接口电路、逻辑主控电路、数据存储电路、行列驱动电路组成。本论文针对二级结构的七段码FED，设计了数字和简单字符动态显示的驱动电路。通过控制高压场效应管的导通与截止来控制共阳极七段码FED的阴极电压，从而实现扫描显示。高压场效应管的逻辑控制信号由可编程逻辑CPLD产生。本论文根据矩阵式FED的特点，设计了实现动态字符和图像的显示驱动电路。针对32×32线的FED显示屏，在单管驱动电路的基础上，修正了充电时间过长的问题，采用双管驱动电路实现动态字符的跳变。采用阳极浮动技术，提高驱动系统的驱动电压，增加FED显示屏的显示亮度，得到了较好的显示结果。针对64×64线和96×72线的FED显示屏，采用分离元件和行列驱动芯片，分别实现了字符滚动显示和16级灰度图像的动态显示。在字符滚动显示实验中，利用FPGA内服的存储资源存储显示信息；在16级灰度图像的动态显示实验中，采用外部EPPROM存储显示信息。在论文的最后，进行了视频显示系统的研究。在碳纳米管FED驱动系统的基础上，引入视频解码系统，组成较完整的视频显示系统。视频解码板采用SV1600，接收DVD机输出的RGB视频信号，在主控电路中进行高4位灰度信号的截取，在96×72线的FED上实现16级灰度图像的显示。更多还原

【Abstract】 Field Emission Display (FED) is one of the cathode ray fluorescent display devices, falls into the catalogue of flat p anel display (FPD). Nowadays, FEDs using nano-carbon tubes as cathode ejecting materials are the most hotspot for research. Its driver circuit, containing high technology, occupies a big percent in the whole cost of device.This paper analyzes the difference in structure between flat panel display and traditional CRT, whose pixel structure and corresponding driver circuit are quite different from each other. As one of the FPDs, CNT -FEDs adop t matrix scanning as dynamic display method and realize grayscales by voltage pulse width modulation (PWM). The whole driver system includes connection circuit, logic controlling circuit, data storage circuit and line & row driver circuit.This paper desig ns a dynamic display driver circuit for diode 7 -segment number FEDs with all anodes connected together . Using logic control signals generated from CPLD of main control circuit to control the high voltage MOSFETs switch circuit for cathode to realize scanning display.This paper designs the driver circuit for dynamic character and image display according to matrix FED. As for 32 × 32 FEDs, on the basis of simple MOSFET driver circuit, using a couple of MOSFETs to overcome the defect of long charge time and realize the dynamic character shifting. Anode voltage floating technology is used to increase the driver voltage of circuit and brighten the display screen. As for 64 X 64 and 96 × 72 FEDs, driven by separate components and line & row driver chips, separately realizes the character scrolling and dynamic image of 16 grayscales, using FPGA inside memory and outside EPPROM for cathode data storage respectively.In the end of the paper, we discuss the video display system. On the basis of original driver system, introducing video decode system to form a relatively integral video display system. Using video decode board SV1600 to translate VGA signals from DVD machine to separate RGB signals for driver circuit, taking the higher 4 bits of the 8 bits data in program to realize the 16 grayscales image display in 96×72 FEDs.更多还原