QQ客服 官方微博 反馈留言

题名	高功率白光用Ce:YAG单晶和陶瓷光源的研究
作者	靳亚硕
文献子类	硕士
导师	李海兵
关键词	Ce:YAG Ce:YAG 单晶 single crystal 陶瓷 ceramic 高密度激光 high density laser 高功率LED high power LED
其他题名	The Study of Ce:YAG Single Crystal and Ceramic Applied in High Power White Light
英文摘要	白光LED由于其节能、光效高、寿命长和反应快的特点被广泛的应用于照明领域。但是随着LED（Light Emitting Diode）芯片功率的不断提高和人们对高功率白光LED的需求，传统的荧光粉配合蓝光芯片的缺点逐渐暴露出来。当LED芯片在高功率下工作时，有一半以上的电能转换为热能，而采用的荧光粉混合硅胶具有不耐高温、光衰大、均匀性差的问题，这使得荧光粉+LED芯片在高功率白光光源的应用上出现了瓶颈。 本文提出采用Ce:YAG单晶和陶瓷取代目前的商用荧光粉来制作高功率白光光源。通过提拉法制备了不同Ce离子掺杂浓度的Ce:YAG单晶，由高温固相法制备了Ce:YAG陶瓷。采用X射线衍射仪、紫外可见吸收光谱仪、积分球测试系统对激光激发的单晶和陶瓷的光学性能做了分析。使用T3ster热瞬态测试仪、FloEFD散热模拟软件等对单晶封装的高功率白光LED光源进行了光学和热学的性能分析。实验的结果如下： XRD的测试表明Ce离子的掺杂并未改变单晶和陶瓷的YAG相。由紫外可见吸收光谱可得，掺Ce的YAG单晶和陶瓷都在460nm附近出现强烈的吸收，表明二者均可以与蓝光LED芯片和LD激光的波长相匹配。而荧光谱的分析表明，采用445nm的光去激发单晶和陶瓷，二者均在530nm的中心附近出现较宽的发射峰。积分球的光电测试分析表明，对于厚度1mm的单晶和陶瓷，在注入电流2.6A的激光激发下，掺杂浓度为0.3mol%的陶瓷和1.5mol%的单晶光通量最高，对应为617.2lm和615.40lm。不过即使在激光输出功率为2.61W，材料中心功率密度达10.8W/mm2的激发下，单晶和陶瓷均未达到饱和，对应的光光转换效率约为240lm/W。实验过程中，Ce:YAG的单晶和陶瓷均未出现温度猝灭的现象。采用T3ster对LED模块的传热进行测试分析，结果表明制作的模块热阻小，传热性能好，不过随着外部温度的提升其散热性能会稍微下降。对模块的光电性能分析表明，在1A的注入电流下，光效为87.3lm/W。 实验中无论是Ce:YAG单晶还是陶瓷，均面临转换光缺少红光的问题，这一问题有待后期进一步研究。不过其显色指数依旧在Ra=60以上，完全可以满足在高功率汽车大灯方面的应用。; White LEDs are widely used in lighting because of their energy saving, high light efficiency, long life and quick response. But as the power of LED (Light Emitting Diode) chips continuously improves and people's demand for high power white LED, shortcomings of the traditional phosphor with blue chips gradually exposed. When LED chips work under high power, there will be more than half of the electrical energy converting into heat energy. Using phosphor powder mixed silicone is not high temperature resistant, and it also has light failure and the problem of poor uniformity. Those problems cause the phosphor powder with LED chip to have a bottleneck in the application of high power white light source In this paper, commercial fluorescence powder was replaced by Ce: YAG single crystal and ceramic to make high power white light source. Ce:YAG single crystal and ceramics, respectively, were prepared by the method of jacquard and high temperature solids. The optical properties of single crystal and ceramic were analyzed by X-ray diffractometer, ultraviolet visible absorption spectrometer. We also used integrating ball test system to analyze their photoelectric properties with laser excitation. Using T3ster thermal transient test instrument, FloEFD radiation simulation software, etc., the properties of optical and heat with the high power white light LED light source with single crystal encapsulation were carried out. The results of the experiment were as follows: The XRD tests showed that the doping of the Ce ions did not change the YAG phase of the single crystal and ceramic. By absorption spectrum analysis, Ce: YAG single crystal and ceramic appeared strong absorption near 460 nm. That meant that they could match the wavelength of blue LED chips and the LD laser. The fluorescence analysis showed that when we used 445nm light to excite single crystal and ceramics, both of them had a wide range of emission peaks near the center of 530nm. Integrating sphere of photoelectric test and analysis showed that for 1 mm thickness of single crystal and ceramic, when the injection current was 2.6 A, Moore doping concentration of 0.3% of ceramic and 1.5% of single crystal had the highest luminous flux, corresponding to 617.2 lm and 615.4 lm. But even when the laser output power was 2.61 W and the materials center power density was 10.8 W/mm2 under the lase excitation, the single crystal and ceramic were still not saturated, corresponding light conversion efficiency was about 240 lm/W. And Ce:YAG single crystal and ceramics did not appear to be quenched in temperature. Using T3ster testing LED module,the results showed that the preparation of the module of thermal resistance was low, the heat transfer performance was good. But as the external temperature increased, its heat dissipation performance would decrease slightly.The photoelectric performance analysis of the module showed that when the injected current was 1A, its photoelectric conversion efficiency was 87.3 lm/W. Whether it was the single crystal or the ceramic, both of them subjected to the question of the lack of red light in the emission light. So we still need to have further investigation. However, the color index was still above 60, which fully satisfied with the application of high power car headlights.
学科主题	光学工程
内容类型	学位论文
源URL	[http://ir.siom.ac.cn/handle/181231/30979]
专题	中国科学院上海光学精密机械研究所
作者单位	中国科学院上海光学精密机械研究所
推荐引用方式 GB/T 7714	靳亚硕. 高功率白光用Ce:YAG单晶和陶瓷光源的研究[D].

个性服务

查看访问统计

相关权益政策

暂无数据

收藏/分享

除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。