基于 In$_{{\bf 1}-x}$Ga$_{x}$P 梯度合金核无镉量子点的制备及 LED 应用

低毒性磷化铟量子点(indium phosphide quantum dot, InP QD)作为最有可能取代有毒重金属镉基量子点的材料, 已经在下一代商业显示和照明领域中显示出巨大潜力. 然而, 合成具有高荧光量子产率(photoluminescence quantum yield, PL QY)的InP QD 仍然具有挑战性. 因此, 提出了以乙酰丙酮镓作为镓源, 在高温下通过乙酰丙酮基对表面配体的活化作用, 生成具有梯度合金核的 In$_{1-x}$Ga$_{x}$P/ZnSe/ZnS 量子点, 有效解决了原有的 InP 与 ZnSe 之间晶格失配的问题; 同时减少核壳界面缺陷, 使量子点的荧光量子产率高达 82%, 所制备量子点发光二极管(quantum dot light-emitting diode, QLED)的外量子效率(external quantum efficiency, EQE)达到 3.1%. 相比传统的 InP/ZnSe/ZnS 结构量子点, In$_{1-x}$Ga$_{x}$P/ZnSe/ZnS 量子点荧光量子产率提高了 25%, 器件的外量子效率提高了近一倍. 该方案为解决 InP 量子点荧光量子产率低、发光器件性能差等问题提供了新的思路.     

纳米压印技术制备表面二维光子晶体发光二极管

研究利用纳米压印技术在氮化镓(GaN)基发光二极管(LED)表面制备二维光子晶体结构对器件出光的影响.利用聚合物(IPS)软模板二次压印技术,在样品表面形成较为完整的掩膜,通过感应耦合等离子体(ICP)刻蚀工艺分别在p-GaN层与ITO层成功制备了较大面积的光子晶体结构,结构周期为465nm,孔状结构直径为245nm.制成芯片后对样品进行测试,结果表明在LED表面制备二维光子晶体结构会导致LED芯片光谱峰值位置发生偏移,同时在p-GaN层制备二维光子晶体结构能够将LED芯片的发光强度提高39%,而在ITO层所制备的光子晶体结构并未对器件的性能有显著的改善.     

大功率发光二极管路灯的一次光学仿真设计

利用反光碗对芯片出射光的角度限制,应用自由透镜曲面对光的聚光和散光作用,研究大功率发光二极管(LED)的配光曲线.设计反光碗和一次光学透镜,通过优化一次光学系统的参数,实现路灯用大功率LED配光曲线具有蝙蝠翼型,接受面上的光斑呈矩形分布的特征.仿真结果表明:设计可以达到路灯要求的光分布,可实现照度均匀度高达0.846,...     

Dependence of the stability of organic light-emitting diodes on driving mode

We investigated the effects of pulsed current (PC) and direct current (DC) driving modes on the stability of organic light-emitting diodes with and without hole-injection layers (HILs).Two different HIL materials were used:copper phthalocyanine (CuPc) and 4,4’,4″-tris(3-methylphenylphenylamino)triphenylamine (m-MDTATA).It was found that the half-lives of devices using PC driving modes were different from those of comparable devices using DC driving modes.For the devices without HILs,with CuPc HILs and with MTDATA HILs,the half-lives of the devices were changed by factors of 1.91,1.41 and 0.86,respectively,when operated in PC rather than DC driving modes.Our analysis of the electrical characteristics of the corresponding hole-only devices showed that the number of holes injected into devices was greatly reduced by inserting an m-MTDATA layer compared with other designs.The results indicate that different ratios of injected electrons and holes can be obtained in these devices.Moreover,these ratios play a dominant role in the dependence of the stability of the device on the driving mode.     

Highly efficient stacked organic light-emitting devices employing a novel intermediate layer

Highly efficient stacked organic light-emitting devices(OLEDs) have been fabricated using Mg:Alq3:BCP/WO3 as a novel intermediate layer,which connects two identical emissive units.The stacked OLEDs consisting of NPB/Alq3 exhibited high current efficiency and brightness characteristics over conventional single-unit device.At 200 mA/cm2,the current efficiency of the stacked OLEDs using the intermediate layers of Mg:Alq3:BCP/WO3 were about 6.85 cd/A,doubling that of the conventional device.The results may prov...     

基于FPGA的智能照明控制系统的设计与分析

使用高性能的可编程FPGA作为控制芯片,以FPGA为核心控制,设计PWM信号输出模块、键盘输入模块、传感器模块、遥控输入模块,分别完成LED调光功能、键盘控制功能、传感器检测功能、遥控控制功能,通过软件实现功能的仿真.     

利用双空穴注入层提高顶发射有机电致发光器件的性能

以铝（Al）为阴极和阳极制备了顶发射有机发光器件。与单独使用三氧化钼（M000或富勒烯（C60）作为空穴注入层相比,利用MoO3/C60双空穴注入层能显著提高器件的性能。表明在Al／MoO3/C60界面处存在较强的偶极作用,极大地降低空穴注入势垒,提高器件性能。     

表面等离激元调控自发辐射研究进展

表面等离激元可以有效地调控自发辐射体的内量子效率和外量子效率,为发展高效新能源提供了可行的方案。特别是近年来,国内外研究人员将该技术应用到固体发光器件中,取得了许多有价值的研究成果。基于这些研究成果,文章介绍了表面等离激元调控固体发光器件自发辐射的原理和实验进展。     

风传感器风向编码器的改进

测风传感器测量风向的主要部件是一种利用格雷码编码的编码器，在已有编码器结构的基础上，通过对发光管和光敏管及码道的重新排列，重新设计转动部件，改进了风向编码器的结构，使新型风传感器的机体体积更小、重量更轻，结构简化。     

Stability study of saturated red polymer light-emitting diodes

Saturated red polymer light-emitting diodes have been fabricated with a single emitting polymer blend layer of poly[2-(2-ethylhexyloxy)-5-methoxy-1,4-phenylenevinylene] (MEH-PPV) and poly[9,9-dioc- tylfluorene-co-4,7-di-2-thienyl-2,1,3-benzothiadiazole] (PFO-DBT15). Saturated red emission with the Commission Internationale de l’Eclairage (CIE) coordinates of (0.67, 0.33) was obtained. The device stability was investigated. The results showed that energy transfer occurred from MEH-PPV to PFO-DBT15, and MEH-PPV improved the hole injection and transportation.