Improved Color Uniformity In White Light-Emitting Diodes Using LiLu(MoO4)2:Sm3+ Combined SiO2 Composite

Abstract

The research herein concerns the composite of red phosphor of LiLu(MoO4)2:Sm3+ (LMOS), yellow phosphor YAG:Ce3+, SiO2 particles, and silicone gel. The LMOS phosphor is created via the sol-gel procedure and supposed to yields significant heat consistency. The concentration of this LMOS phosphor is fixed at around 10 wt.% and the concentration of SiO2 particles is modifed. This is to influence the scattering performance of the composite to achieve the better color distribution. After sample creation, we analyzed the luminescence of the LMOS in the composite and the effects of the composite with different SiO2 dosages on the commercial light-emitting diode (LED). When excited via 405-nm ultraviolet, the samples generate red ray under 648 nm matching the shift between 4G5/2 and 6H9/2 for the ion of Sm3+. With high SiO2 amounts, the color difference is reduced, and the luminosity is enhanced. The correlated color temperature is also lower, resulting in a warmer white light for the packed LED. However, the color rendering index declines, which could be attributed to the green and blue color deficiency while the red color is dominant. From the tested outcomes, LiLu(MoO4)2:Sm3+@SiO2­ composite is validated to be effective at improving chromatic uniformity for white-ray diodes.

Keywords

• blue ingan chips
• color rendering index
• correlated color temperature
• white-light-emitting diodes