Open AccessUsing SiO2 nano-particles for better color uniformity and lumen output in 8500 K conformal and in-cup white LEDs
Author(s) -
My Hanh Nguyen Thi,
Nguyen Thi Phuong Loan,
Thuc Minh Bui,
Tri-Vien Vu
Publication year - 2021
Publication title -
international journal of power electronics and drive systems/international journal of electrical and computer engineering
Language(s) - English
Resource type - Journals
eISSN - 2722-2578
pISSN - 2722-256X
DOI - 10.11591/ijece.v11i5.pp3897-3902
Subject(s) - light emitting diode , phosphor , materials science , doping , optics , refractive index , optoelectronics , analytical chemistry (journal) , chemistry , physics , chromatography
In the effort of improving the performance of white light LEDs devices (WLEDs), the SiO 2 nano-particles were applied and have shown a significant impact on the optical properties. Specifically, the light output of the lighting devices is enhanced when a mixture of SiO 2 particles and silicone gel is diffused on the encapsulation layer surface. This enhancement is the result of light scattering from SiO 2 that strengthens the emitted blue light at further angles and reduces the color discrepancy. The evidence is that CCT deviation in SiO 2 -doped structure decline from 1000 K to 420 K in -70° to 70°. In addition, the SiO 2 with refractive index in between the phosphor material and outside environment allows light to be emitted outward more effectively. This lighting enhancement of SiO 2 -doped structure increases the lumen output by 2.25% at 120 mA power source in comparison to structure without SiO 2 . These experimental outcomes suggest that SiO 2 is an effective material to add in WLEDs structure for better lighting efficiency.