Korean Institute of Surface Engineering

pISSN : 1225-8024 | eISSN : 3399-8403


한국표면공학회지 (40권2호 103-106)

Effect of Yellow Phosphor on Characteristics of White Light Emitting Diode

백색 발광다이오드의 특성에 대한 황색 형광체의 영향

Chang, Ho-Jung;Son, Chang-Sik;Hur, Jae-Sung;

단국대학교 전기공학과;신라대학교 광전자공학과;고려대학교 재료공학과;
Dept. of Electronics Engineering, Dankook Univ.;Dept. of Photonics, Silla Univ.;Dept. of Materials of Engineering, Korea Univ.;

DOI : 10.5695/JKISE.2007.40.2.103


We have investigated the optical and electrical properties of surface mounted white light emitting diode (LED) chips prepared by using yellow phosphors on the blue LED chip. The yellow phosphor mixed with transparent epoxy was coated on the prepared LED chip. The optimum mixing conditions with epoxy and yellow phosphor is obtained at the mixing ratio of epoxy:yellow phosphor = 97:3 wt%. The maximum luminance and light emitting efficiency are above $80,000cd/m^2$ and 23.2 lm/W, respectively, at the bias voltage of 2.9 V. There was no distinct change in the luminance strength with changing of the yellow phosphor ratios. The current of the white LED chip is about 30 mA at 2.9 V.


White LED;Yellow phosphor;Luminance;