White LED Light Characteristics as a Function of Phosphor Particle Size

摘要

The influence of phosphor particle size on phosphor concentration in white LEDs and on the optical performance of the resulting device was investigated. Phosphor photoluminescent properties show that increasing particle sizes result in higher emission intensities. White LEDs were fabricated based on YAG phosphor of narrow particle size distribution. The phosphor concentration required to obtain LEDs of the same chromaticity is higher for large phosphor particles. Luminous efficacy increases with increasing phosphor particle size. Monte-Carlo ray tracing was used to simulate the changes of LED light emission related to particle size variation. Simulated results matched well with experimental data.