Discoloration Modes and Mechanism Discussion of Packaging Materials in White LEDs
Solid state lighting technology has achieved great progress in recent years,especially in white light emitting diodes (LEDs).However,some problems are found in the packaging technology and widespread application.Under long time exposing to high temperature and photon energy,packing materials will be resulted in an obvious discoloration and yellowing phenomenon which will adversely affect the light efficiency of white LEDs.Discoloration may occur at various packaging materials,such as reflector cup,die-attach adhesive,phosphor and silicone.Different materials have different discoloration mechanisms.In this paper,some major discoloration modes and possibilities of white LED packaging materials are discussed.To better understand the discoloration of different materials,some pictures and examples by our lab and the other researchers are presented.Moreover,some experiments about LED leadframes with Energy Dispersive X-Ray Spectroscopy (EDX) results are designed to verify the reasons of the reflector cup discoloration.
国内会议
宜昌
英文
1-5
2014-05-15（万方平台首次上网日期，不代表论文的发表时间）