2-phosphor-converted white light-emitting diodes using oxynitrideitride phosphors

摘要

Green α-sialon: Yb~(2+) and red Sr_2Si_5N_8: Eu~(2+) oxynitrideitride phosphors have been demonstrated as potential downconversion luminescent materials for white light-emitting diodes (LEDs). In this letter, the authors attempt to fabricate white LEDs by combining α-sialon: Yb~(2+) and Sr_2Si_5N_8: Eu~(2+) with a blue LED die and report their optical properties. These two phosphors lend themselves for use in 2-phosphor-converted white LEDs with promising properties: a wide range of tunable correlated color temperature (2700-6700 K), acceptable color rendering index (82-83), and luminous efficacy (17-23 lm/W). These LEDs are acceptable for general lighting.