【摘要】 利用发射波长为470nm的蓝光发光二极管作为基础光源,通过荧光粉转换方法制备白光发光二极管,荧光粉主要采用稀土激活的铝酸盐Y3Al5O12∶Ce3+(YAG)。在工作电流为15mA条件下,所研制的白光LED的法向光强为2890mcd;色坐标为x=0 29,y=0 33;显色指数为77;流明效率为14 9lm/W。研究制备了不同色温的白光LED,色温范围从2700～8000K,研究了色温与色坐标之间的对应关系。并且与国外同类产品进行比较,部分指标已经超过了国外同类产品水平。更多还原

【Abstract】 White lightemitting diodes were fabricated by phosphor conversion. The blue LED chip (470nm, GaNbased) was used as primary light source and Y3Al5O12∶Ce3+ (YAG) phosphors was used as light changing materials. The excitation spectrum peak of the phosphor is the same as the luminescent peak of blue chip at 470nm. The PL spectrum peak of the phosphors is at 570nm. The white light was yielded by mixing 470nm with 570nm. The luminescent intensity of white LED is 2 890mcd. The color coordinates of white LED is x=029, y=033 and the color index is 77. The efficiency of the white LED is 149 lm/W. The light conversion efficiency of phosphors is 269 from blue LED to white LED. The white LEDs with different color temperature from 2 700～8 000K were fabricated. The relationship between the color temperature and the color coordinates of white LED was investigated. When the color temperature is under 3 700K, the color coordinates x and y are bigger than 04. When the color temperature is above 8 000K, the color coordinates x and y are smaller than 03. When the color coordinates x and y are 033 respectively, the color temperature is about 5 500K. 更多还原