用于大功率LED/LD的YAG:Ce荧光陶瓷在固态照明的研究进展

Research Progress of YAG:Ce Fluorescent Ceramics for High-power LED/LD in Solid-state Lighting

荧光陶瓷是将荧光粉末直接烧结或配合其他烧结助剂在高温高压下烧结制备的透明陶瓷。在LED/LD芯片的激发下,不同的荧光陶瓷片会发出不同类别的光。在大功率LED/LD照明方面,相比于荧光有机材料和荧光玻璃,新型的YAG∶Ce荧光陶瓷具备热导率高、热稳定性好、高透光性等优点而被广泛研究,但由于缺乏热稳定性好的红光成分,制备的LED/LD照明设备偏向于冷色光,明显存在显色指数低、色温高的问题。随着LED/LD输出功率的提高,对荧光陶瓷热导率的要求也越高。综述了近年来研究者们在YAG∶Ce荧光陶瓷制备中如何提高照明器的发光效率、解决红色成分缺失问题以及控制热导率的最新进展。最后,对大功率LED/LD新型荧光陶瓷的发展趋势进行展望。

Fluorescent ceramics are transparent ceramics prepared by sintering fluorescent powder directly or with other sintering aids at high temperature and pressure.Under the excitation of LED/LD chip,different fluorescent ceramic plates will emit different types of white light.Compared to fluorescent polymer and fluorescent glass,the new YAG:Ce fluorescent ceramic applied to high-power LED/LD lighting has the advantages of high thermal conductivity,good thermal stability and high light transmittance,so the new YAG:Ce fluorescent ceramic has been widely studied.However,due to lack of thermally stable red phosphor,the prepared LED/LD lighting equipment is biased towards cold light,which obviously has the problems of low color rendering index and high correlated color temperature.With the increase of LED/LD output power,the requirements for the thermal conductivity of fluorescent ceramics are also higher.This article reviews the latest developments in how researchers have improved the luminous efficiency of luminaires and solved the problem of missing red components in the preparation of YAG:Ce fluorescent ceramics in recent years.Finally,this article prospects the development trend of new fluorescent ceramics based on application of high-power LED/LD.