Flexible active matrix addressed displays manufactured by printing and coating techniques

A flexible electrochromic active matrix addressed display, including 8 × 8 pixels, is demonstrated by using solution processing based on standard printing and coating manufacturing techniques. Each organic electrochromic display (OECD) pixel and its corresponding organic electrochemical transistor (OECT) are located on different sides of the flexible PET substrate. Electronic vias generated through the plastic substrate connects each OECD pixel with one addressing OECT. When comparing this display with actively addressed OECDs with all its components located on the same side, the present approach based on this electronic via substrate provides an enhanced pixel resolution and a relatively more simplified manufacturing process. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012     

High-performance and current crowding-free InGaN-GaNbased LEDs integrated by an electrically-reverse-connected Schottky diode and a Mg-delta doped p-GaN

This work demonstrates high-performance and current crowding-free InGaN/GaN light-emitting diodes (LEDs) using an electrically-reverse-connected Schottky diode (SD) and an Mg-delta (δ) doped layer.Poss...     

Reliability and optical properties of LED lens plates under high temperature stress

In this investigation the thermal degradation mechanisms of Bisphenol A Polycarbonate (BPA-PC) plates at the temperature range 100–140 °C are studied. The BPA-PC plates are currently used both in light conversion carriers in LED modules and optical lenses in LED-based products. In this study BPA-PC plates are aged at elevated temperature of 100–140 °C for a period up to 3000 h. Optical and chemical properties of the thermally-aged plates were studied using UV–Vis spectrophotometer, FTIR–ATR spectrometer, and integrated sphere. The results show that increasing the thermal ageing time leads to yellowing, loss of optical properties, and decrease of the light transmission and of the relative radiant power value of BPA-PC plates. The results also depict that there is not much discoloration within the first 1500 h of thermal ageing. The rate of yellowing significantly increases at the end of this induction period. Formation of oxidation products is identified as the main mechanism of yellowing. An exponential-based reliability model is also presented to calculate the rate of degradation reaction and to predict the life-time of BPA-PC plates.     

户外LED显示屏图像质量主观评价初探

当前户外LED显示屏的图像质量主要靠业内人士进行简单的主观评价，不确定因素多，尚未形成规范的评价标准。本文参考通用的图像质量主观评价方法，针对LED显示屏显示特性，探讨了主观评价中的各个环境因素的控制方法，并定义了一系列主观评价测试图像的类型，能对显示屏的均匀性、对比度、色彩还原性等显示性能进行更规范更全面的评价。     

LED节能灯的安规要求

根据CTL发布的DSH 0743决议,归纳了LED节能灯测试标准中的要求,主要包含对灯头、防触电、灯头温升、绝缘材料、异常状态、结构的考核,以及灯的光生物学安全考核。     

InGaN基高压LED和传统大功率LED的发光效率比较

主要从三个不同角度探究并分析了基于In Ga N材料的高压LED的发光效率优于传统大功率LED的原因。为了保证实验结论的可靠性,文中所采用的实验样品具有相同的芯片尺寸和材料以及相同的封装结构。经过大量的实验证明,更均匀的电流分布和小芯片间隙的出光,使得高压LED的发光效率优于传统大功率LED。结果显示,在相同的1 W输入功率下,高压LED的发光效率比传统大功率LED高大约4.5%。     

基于蓝宝石纳米图形衬底上氮化镓生长的研究

利用两步生长法在蓝宝石纳米图形衬底（NPSS）上生长得到高质量的氮化镓薄膜。通过XRD和SEM对薄膜质量的表征和研究发现,为得到高质量的氮化镓（GaN）薄膜,在NPSS上生长时得到的最优缓冲层厚度为15nm,而在微米级尺寸的图形衬底（MPSS）上得到的最优缓冲层厚度远大于15nm。同时,在NPSS上生长氮化镓薄膜的过程中观察到一个有趣的现象,即GaN在NPSS上生长的初始阶段,氮化镓晶粒主要在图形之间的平面区域生长,极少量的GaN在衬底图形的侧面上聚集生长。这一有趣的现象明显不同于GaN在MPSS上的生长过程。接着,又在NPSS上生长了GaN基LED结构,并对其光电性能进行了研究。     

光栅数显装置的优化设计与实现

本文针对传统的数显装置设计方案,提出一种基于CPLD和单片机的数显装置的优化设计方案,本方案采用CPLD芯片EPM240对光栅尺输出信号进行处理,单片机读取EPM240处理后的数据并实时显示。全文给出了CPLD设计的仿真结果,制作了装置实物,并进行了相关比对实验。实验证明所设计的数显装置具有数据处理和实时显示等功能,并有着较高的测量精度和稳定性,可用于实际的光栅位移测量输出系统。     

平板显示设备贴附技术分析

随着国内平板显示设备日新月异的发展,其生产中的关键技术贴附技术也得到了长足发展。在整个平板显示器的生产过程中,很多地方都用到了贴附技术。由于材料及工艺的不同,选择的贴附方式也不尽相同。针对目前几种常见的贴附技术进行详细分析,提出不同贴附技术的优缺点及注意事项。在实际的生产过程中要根据材料及工艺要求选择合适的贴附技术。     

LED外延片上芯片静电击穿的测试分析

利用静电仪和HBM模型研究了GaN基LED外延片上芯片的抗静电性能,并根据pn结势垒电容的特性,对实验结果进行了分析.实验结果表明,缺陷击穿与外延片的工艺有着密切的关系;随着外延片上芯片尺寸的增大,其抗静电能力也随之增强.