White Light-Emitting Diodes Using Sr-Containing Sialon Phosphors

We have successfully developed white light-emitting diodes (LEDs) that are highly luminescent with excellent color rendering by utilizing a green-emitting phosphor (Sr3Si13Al3O2N21:Eu2+) and a red-emitting phosphor (Sr2Si7Al3ON13:Eu2+). The LEDs have luminous efficacy of 53-60 lm/W and color rendering index Ra of 95-98 in a wide range of tunable correlated color temperatures (3200-6100 K). We found that white LEDs using these phosphors have excellent properties at high power output. Hence, these phosphors have potential applications in white LEDs for lighting. (C) 2012 The Japan Society of Applied Physics