COB LED光源封装密度对发光效率的影响
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摘要
采用镜面率基板,制作了18 W、24 W和36 W等不同封装密度的COB LED光源,研究了脉冲驱动时不同封装密度COB LED光源发光效率的电流依赖关系和恒流驱动时的发光效率维持率。通过采用沉粉技术,提高了高密度封装COB光源的发光效率和恒流发光效率维持率。研究结果表明:随着封装密度的增加,光源的发光效率呈现下降趋势,恒流(300 m A)驱动时,24 W、36 W光源发光效率分别下降了1. 31%和10. 87%。相比于传统荧光粉涂覆工艺,恒流驱动时,发光效率初始值提高了1. 00%,表现出更好的光效维持率;在持续点亮30 min时,发光效率维持率达到97. 60%,高于传统荧光粉涂覆工艺2. 16%。
Using the mirror aluminum substrate,the COB LED light sources are produced with different package densities such as 18 W,24 W and 36 W. The current dependence under pulse drive of the luminous efficiency of the COB LED light source with different package densities and the maintenance rate of the luminous efficiency with the constant current drive are studied. The luminous efficiency and constant current luminous efficiency maintenance rate of the high density package COB light source is improved by using the technology of deposited phosphor process. The results show that the luminous efficiency of the 24 W and 36 W light sources is decreased by 1. 31% and 10. 87%,when is driven by constant current( 300 mA). Compared with the traditional phosphor coating process,when driven by the constant current,the initial value of the luminous efficiency is increased by 1. 00%. At the same time,the light efficiency maintenance rate is better,the luminous efficiency of the light emitting efficiency is 97. 60% with 30 minutes continuous lighting,higher than the traditional phosphor coating process by 2. 16%.
Using the mirror aluminum substrate,the COB LED light sources are produced with different package densities such as 18 W,24 W and 36 W. The current dependence under pulse drive of the luminous efficiency of the COB LED light source with different package densities and the maintenance rate of the luminous efficiency with the constant current drive are studied. The luminous efficiency and constant current luminous efficiency maintenance rate of the high density package COB light source is improved by using the technology of deposited phosphor process. The results show that the luminous efficiency of the 24 W and 36 W light sources is decreased by 1. 31% and 10. 87%,when is driven by constant current( 300 mA). Compared with the traditional phosphor coating process,when driven by the constant current,the initial value of the luminous efficiency is increased by 1. 00%. At the same time,the light efficiency maintenance rate is better,the luminous efficiency of the light emitting efficiency is 97. 60% with 30 minutes continuous lighting,higher than the traditional phosphor coating process by 2. 16%.
引文
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[4]古志良,李炳乾,范广涵,等.COB白光LED的光提取效率研究[J].半导体光电,2015,36(5):753-755.
[5]兰海,邓种华,刘著光,等.LED的COB封装热仿真设计[J].发光学报,2012,33(5):535-539.
[6]KIM J K,LUO H,SCHUBERT E F,et al.Strongly enhanced phosphor efficiency in Ga In N white light-emitting diodes using remote phosphor configuration and diffuse reflector cup[J].Jpn.J.Appl.Phys.,2005,44(21):L649-L651.
[7]KANG D Y,WU E B,WANG D M.Modeling white lightemitting diodes with phosphor layers[J].Appl.Phys.Lett.,2006,89(23):231102-1-3.
[8]YU R Y,JIN S Z,CEN S Y,et al.Effect of the phosphor geometry on the luminous flux of phosphor-converted lightemitting diodes[J].IEEE Photon.Technol.Lett.,2010,22(23):1765-1767.
[9]肖华,吕毅军,徐云鑫,等.传统白光LED与远程荧光粉白光LED的发光性能比较[J].发光学报,2014,35(1):66-72.