Enhancing spectral uniformity in full-spectrum white LEDs using an SiO₂ aerogel encapsulant

Achieving high luminous efficacy and spectral uniformity in full-spectrum white LEDs (FS-WLEDs) remains challenging due to phosphor sedimentation during encapsulant curing. This study introduces an SiO₂ aerogel-doped composite that provides direct evidence of sedimentation suppression via Ce-line scan EPMA. Incorporating 1.0 wt% SiO₂ aerogel into a four-phosphor InGaN-based FS-WLED package not only mitigated phosphor precipitation but also enhanced light conversion efficiency, leading to a 7.8% increase in luminous efficacy (110 lm/W), an average color rendering index improvement from 91 to 95, and a 194 K reduction in angular color temperature deviation. Long-term tests (1008 h at 150°C) confirmed its stability. This scalable, low-cost approach combines sedimentation control, material savings, and proven reliability for next-generation solid-state lighting.