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YAG:Ce~(3+)玻璃陶瓷白光LED的发光特性 总被引:3,自引:1,他引:2
用化学共沉淀法制备掺铈钇铝石榴石(YAG:Ce3+)前驱体,以B2O3-Al2O3-SiO2-Na2O为玻璃基质制作Ce3+掺杂YAG玻璃陶瓷,并封装成玻璃陶瓷白光发光二极管(LED)。改变玻璃陶瓷基片厚度和外形,测量玻璃陶瓷白光LED的光电色参数,并与常规涂敷YAG荧光粉方法制作的白光LED进行对照比较。结果表明,玻璃陶瓷白光LED发射光谱波形与普通白光LED光谱基本一致。玻璃陶瓷基片从0.50mm变化到0.90mm厚时,相关色温(CCT)从4 182 K增加到8862K。0.60mm厚平板玻璃陶瓷基片封装成的白光LED荧光能量转换效率约为20%,中心CCT为6396K,-85°和+85°视角CCT分别为5921K和5898K;而平凸玻璃陶瓷基片封装成的白光LED,-85°和+85°视角CCT变化范围可控制在150K范围内。 相似文献
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通过高温固相法制备了白光LED用Sb3+掺杂的Y1.94-yGdSbyAl5O12:0.06Ce荧光粉,使用荧光分光光度计研究了样品的发光性能,并采用紫外-可见-近红外光谱分析系统分析了所制荧光粉的封装性能。结果表明,Y1.94-yGdSbyAl5O12:0.06Ce荧光粉为立方晶系,其发射中心波长为550 nm,Sb3+掺杂有助于提高YAG:Ce的发光强度。将合成的Y1.92GdSb0.02Al5O12:0.06Ce(CL-Y-550)荧光粉封装成白光LED,其平均色温为5 376 K,属于冷白;平均显色指数为81.2,达到了基本的应用水平。 相似文献
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运用基于蒙特卡罗的光线追迹方法,对采用"光转换"兼"多色混合"技术的白光LED的显色指数、相关色温、光通量、光辐射功率、荧光粉颗粒密度和色坐标进行了仿真计算和优化选择。通过改变红、绿、蓝三种LED芯片的组合方式和红、绿、黄三种荧光粉的混合方式及各色荧光粉的密度,在保证有合理的光通量输出的条件下,得到了不同色温区的高显色指数白光LED。从显色指数角度看,冷白、正白和暖白光应分别选择BBB芯片+绿、红色荧光粉、BBB芯片+黄、红色荧光粉和RBB芯片+黄色荧光粉组合。实验上测试了采用这几种组合方式的白光LED光谱、显色指数、色温、光通量和色坐标,实验数据与仿真结果基本吻合。 相似文献
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文章介绍了小颗粒 YAG:Ce 荧光粉的三种合成方法.这种荧光粉受到蓝光 LED 发出的光线的激发会发出黄光.在合成的 pcLEDs 里,蓝光和黄光混合形成了白光.本文解释了这种涂有 YAG:Ce 荧光粉的 pcLED 的色点的依赖性以及通过添加修复晶格点阵的催化剂以改变这种依赖型的方法.另外,文章还讨论了 Ce3 聚集中心的YAG:Ce 荧光粉的效率的测量、烧成温度、激发波长. 相似文献
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通过分析LED封装材料中固晶胶对白光的影响,给出了不同固晶胶对白光LED光衰的效果图;通过分析荧光粉对白光LED光性能的影响,给出了用同一成分荧光粉加不同波长蓝光芯片形成的CCT/Ra关系图、同一波长蓝光芯片加不同成分荧光粉CCT/Ra关系图和蓝光芯片激发下荧光粉的相对亮度随温度的变化;通过分析配粉胶对白光LED光性能的影响,给出了不同折射率硅胶封装的白光LED光衰情况和膜清洗后不同折射率硅胶封装的白光LED光衰情况影响。从而可以依据光性能的需要,选择相应封装材料,并进行白光LED的封装设计与制造。 相似文献
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YU Xin-mei RAO Hai-bo HU Yue LI Jun-fei HOU Bin 《半导体光子学与技术》2007,13(2):97-103
As the blue and yellow lights are complementary colors, a blue InGaN LED chip is coated hy a yellow phosphor film to generate white light based on luminescence conversion mechanism. The emitted light of a blue LED is used as the primary source for exciting fluorescent material such as cerium doped yttrium aluminum garnet with the formula Y3Al2O12 : Ce^3+ (in short: YAG : Ce^3+ ). The matching of the spectrum of the blue LED chips and the YAG : Ce^3+ yellow phosphor is studied to improve the conversion efficiency. The packaging methods and manufacturing processes for high power single chip-white LEDs are introduced. The uniformity of the output white light is investigated. Based on the characteristics of the high power white LEDs, some approaches and processes are suggested to improve the light uniformity when they are fabricated. The effectiveness of those approaches on the improvement of LEDs is discussed in detail and some interesting conclusions are also presented. 相似文献
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We packaged a series of high power white LEDs by covering the blue LED chips with yellow phosphor, red phosphor and the two phosphors mixed by appropriate mass ratio,respectively,and discussed the excitation and emission spectrum of yellow phosphor and red phosphor and the characteristics of the LEDs.We found that the luminous efficacy of the white LEDs covered with the two phosphors mixed by appropriate mass ratio was lower than that of the white LEDs covered with yellow phosphor,but the color rendering index was improved observably. 相似文献
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We packaged a series of high power white LEDs by covering the blue LED chips with yellow phosphor, red phosphor and the two phosphors mixed by appropriate mass ratio, respectively, and discussed the excitation and emission spectrum of yellow phosphor and red phosphor and the characteristics of the LEDs. We found that the luminous efficacy of the white LEDs covered with the two phosphors mixed by appropriate mass ratio was lower than that of the white LEDs covered with yellow phosphor, but the color rendering index was improved observably. 相似文献