초록 |
Solid-state lighting based on phosphor converted white-emitting diodes has attracted considerable attention as a replacement for conventional incandescent and fluorescent light sources due to their advantages compared with their conventional counterparts, such as luminous efficiency, lower energy consumption, diversity of packaging forms, long operating lifetime, and environmental safety. The YAG:Ce3+ can be applied in various forms such as phosphor in resins, the phosphor in silicone and phosphor in the glass, but these are not thermally stable. On the other hand, polycrystalline phosphors have an advantage of good thermal stability. Therefore, studies on polycrystalline phosphors are under way. YAG:Ce3+ ceramic phosphor plate (CPP) improved both yellow-ring phenomenon and the light-extraction efficiency Because of Al2O3 particle embedded in the cubic YAG:Ce3+ CPP as the second phase. Also, the Al2O3 particle has a birefringence effect due to its hexagonal structure, and its scattering of the light reduces the yellow-ring effect. In this study, we prepared YAG:Ce3+ CPP with various amounts of Al2O3. The characteristics were investigated according to the addition amount of Al2O3 and optimized. The luminous properties of the YAG:Ce3+ and Al2O3 are improved when compared to the YAG:Ce3+ alone, and hence, the luminous emittance, luminous flux, and conversion efficiency are improved. We suggest that CPP is a next-generation material for solid-state laser lighting(SSL) in automotive applications. |