针对LED高光效、低功耗的要求,在分析LED光学性能的基础上,采用了COB（chip on board）即板上芯片封装技术。研究了不同电流下和点亮不同时间后,分析其LED光通量、光效和色温。研究分析影响LED光学性能的因素并进行测试。结果表明,用两...针对LED高光效、低功耗的要求,在分析LED光学性能的基础上,采用了COB（chip on board）即板上芯片封装技术。研究了不同电流下和点亮不同时间后,分析其LED光通量、光效和色温。研究分析影响LED光学性能的因素并进行测试。结果表明,用两种色温接近3 000 K的样品,电流由500 m A增大到900 m A,色温升高了1.685%、2.626%,光通量也随着电流的变大而升高68.532%、84.625%,但相反光效却降低了13.535%、9.971%;而在电流保持不变的情况下,点亮的时间由0~1 min、0~5 min、0~10 min,其色温分别上升了0.537%、1.209%、2.384%;0.369%、1.104%、2.943%,同时,光通量分别降低1.474%、4.855%、7.493%;2.073%、3.859%、7.793%,光效也分别降低2.527%、4.617%、6.671%;2.171%、4.903%、7.579%。实验发现,电流与点亮时间直接影响LED光学性能。展开更多
Increasing light extraction efficiency is an important task when it comes to manufacturing a powerful white light emitting diode with high luminous flux per watt. In this paper the fabrication of a pyramid-shaped 3-di...Increasing light extraction efficiency is an important task when it comes to manufacturing a powerful white light emitting diode with high luminous flux per watt. In this paper the fabrication of a pyramid-shaped 3-dimensional phosphor coating is reported. It is represented by a phosphor cover, shaped into an array of pyramid like formations. It is proposed that such a structure can improve the light extraction efficiency and the color distribution characteristics of any phosphor-converted white LED. The luminous flux and luminous efficacy are being studied as a function of the forward current across the die. It was found out that with this kind of technique it was possible to achieve an 8% - 14% increase in the efficacy of the pc-LED. This increase of light output power is being attributed to the reduction of the phenomena of total internal reflection (TIR) inside the packaging module.展开更多
基于蒙特卡罗方法模拟、计算并分析了芯片类型、大小、间距、数量以及布局对GaN基发光二极管(LED)集成封装器件COB(Chip On Board)能效的影响。计算结果表明:在芯片间距小于200μm且芯片尺寸或布局等参数相同的条件下,正装LED COB的能...基于蒙特卡罗方法模拟、计算并分析了芯片类型、大小、间距、数量以及布局对GaN基发光二极管(LED)集成封装器件COB(Chip On Board)能效的影响。计算结果表明:在芯片间距小于200μm且芯片尺寸或布局等参数相同的条件下,正装LED COB的能效最低,其次为倒装LED COB,垂直结构芯片的能效最大。当芯片间距大于200μm,3种LED COB的能效趋向饱和。芯片尺寸增加或数量减少可使正装和倒装芯片COB的能效上升,而垂直结构COB的能效基本保持不变。加入图形衬底可提高同样尺寸或布局的正装芯片COB封装器件的能效,但使倒装芯片COB的能效恶化。分析表明:芯片的侧面出光量占整个芯片出光量的比值以及相邻芯片材料的吸收对3种类型COB封装器件的能效有决定性影响。文中还针对正装芯片COB设计了新型菱形芯片布局,与常规正方形芯片布局的COB相比,其能效提高了6.2%。展开更多
文摘针对LED高光效、低功耗的要求,在分析LED光学性能的基础上,采用了COB（chip on board）即板上芯片封装技术。研究了不同电流下和点亮不同时间后,分析其LED光通量、光效和色温。研究分析影响LED光学性能的因素并进行测试。结果表明,用两种色温接近3 000 K的样品,电流由500 m A增大到900 m A,色温升高了1.685%、2.626%,光通量也随着电流的变大而升高68.532%、84.625%,但相反光效却降低了13.535%、9.971%;而在电流保持不变的情况下,点亮的时间由0~1 min、0~5 min、0~10 min,其色温分别上升了0.537%、1.209%、2.384%;0.369%、1.104%、2.943%,同时,光通量分别降低1.474%、4.855%、7.493%;2.073%、3.859%、7.793%,光效也分别降低2.527%、4.617%、6.671%;2.171%、4.903%、7.579%。实验发现,电流与点亮时间直接影响LED光学性能。
文摘Increasing light extraction efficiency is an important task when it comes to manufacturing a powerful white light emitting diode with high luminous flux per watt. In this paper the fabrication of a pyramid-shaped 3-dimensional phosphor coating is reported. It is represented by a phosphor cover, shaped into an array of pyramid like formations. It is proposed that such a structure can improve the light extraction efficiency and the color distribution characteristics of any phosphor-converted white LED. The luminous flux and luminous efficacy are being studied as a function of the forward current across the die. It was found out that with this kind of technique it was possible to achieve an 8% - 14% increase in the efficacy of the pc-LED. This increase of light output power is being attributed to the reduction of the phenomena of total internal reflection (TIR) inside the packaging module.
