共查询到20条相似文献,搜索用时 906 毫秒
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LED路灯透镜的二次光学设计介绍 总被引:8,自引:1,他引:8
LED的二次光学元件设计对LED路灯的配光及光学输出效率至关重要。良好的道路照明要求LED路灯的配光为长方形的光型,路灯发出的所有光刚刚可以覆盖住马路,而马路之外的光污染几乎为零。非对称自由曲面二次光学元件的采用可以使LED路灯的长方形配光直接在单个LED模组上实现。整体路灯只需要将这些LED模组阵列按照相同方向排列即可,从而可以简化路灯机构、散热及控制电源的设计。本文介绍了LED路灯的二次光学设计,及一种用于LED路灯的自由曲面二次光学透镜的设计方法。 相似文献
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远程荧光LED器件影响因素研究 总被引:1,自引:0,他引:1
远程荧光技术是传统LED封装散热不良问题的解决方法之一。本文用红色和黄色荧光粉以及光固化树脂,通过光同化方式制备了荧光转换膜,并制备了简单的远程白光LED器件,研究了荧光粉组成、芯片与荧光转换膜的距离及输入电流对远程自光LED器件光学特性的影响,实验结果表明,荧光粉的组成比例对显色指数,色温等都有影响,而荧光转换膜与芯片的距离以及输入电流对器件的光学特性影响不大。本实验还通过添加光扩散剂解决了白光LED芯片发光刺眼问题。研究结果可为新型白光LED的结构设计提供参考。 相似文献
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学生宿舍照明环境与学生的学习和生活相关。为提升学生宿舍的光环境质量,提出了一款全新升级的学生宿舍用LED灯产品。该款LED灯以光学设计、散热分析、场景模拟的开发方法达到了相关要求,且具有弧形反光罩结构、三向线性发光等特点。 相似文献
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Grillot P. N. Krames M. R. Zhao H. Teoh S.-H. 《Device and Materials Reliability, IEEE Transactions on》2006,6(4):564-574
Both fixed current density and variable current density stress conditions are used to study light output degradation of (AlxGa1-x)0.5In0.5P light-emitting diodes (LEDs) as functions of LED stress current and LED stress time. Quantification of the resulting data indicates that (AlxGa1-x)0.5In0.5P LED degradation, D, is a linear function of current density, J, and a logarithmic function of stress time, t, for stress times as long as 60 000 hours in duration. For stress times long enough and current densities high enough to saturate any short-term effects (AlxGa1-x)0.5In0.5P LED degradation is therefore quantified by the empirical equation D=D1 +D2J+(D3+D4J)ln(t), where D1 , D2, D3, and D4 are independent of LED stress current and LED stress time. Within the limits of the data presented here, this equation is shown to accurately describe light output degradation of individual LED lamps, the average degradation behavior of individual LED wafers, and the average degradation behavior of a distribution of multiple LED wafers. The resulting expression may thus provide helpful guidance in quantifying the tradeoff between LED flux and LED degradation, both of which depend linearly on current density 相似文献
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