Luminous efficacy enhancement of phosphor-in-glass based white light-emitting diodes through patterned structure

A patterned packaging structure was proposed to enhance the luminous efficacy of multiple phosphor-in-glass (PiG) based white light-emitting diodes (WLEDs). In this work, a red and yellow patterned PiG was prepared by using screen-printing and low temperature sintering. The comparison experiments between the conventional mixed PiG structure and patterned PiG structure were conducted. Compared with the mixed PiG structure, the luminous efficacy of patterned PiG structure is increased by 7.7% at the driving current of 350 mA. This is a beginning of luminous efficacy enhancement through patterned phosphor layer, and it may inspire new LED packaging structures.