摘要
In this study, small- and large-particle-diameter phosphor powders were mixed together(hybrid phosphors)to balance light efficacy and angular color uniformity and pursue optimal results. Phosphor with small-particlediameter of 4 lm was employed and it was mixed into each large-particle-diameter phosphor of 10, 16, 22, and 26 lm,at mass percentage from 0 % to 50 % with an interval of10 %, respectively. Remote phosphor package was adopted and overall phosphor concentration was kept constant for better comparison. Moreover, absorption coefficient labs,scattering coefficient lscaand extinction coefficient lext of each hybrid phosphors were calculated based on Mie theory to further discuss the experiment results. Results show that, the introduction of small-particle-diameter phosphor to large one can highly improve angular color uniformity while only slightly reduce light efficacy. The optimal performance with angular color uniformity of91.6 % as well as normalized light efficacy of 95.7 % is achieved in the white light emitting diode with hybrid phosphors consisting of 60 wt% powder of 22 μm and40 wt% powder of 4 μm.
In this study, small- and large-particle-diameter phosphor powders were mixed together(hybrid phosphors)to balance light efficacy and angular color uniformity and pursue optimal results. Phosphor with small-particlediameter of 4 lm was employed and it was mixed into each large-particle-diameter phosphor of 10, 16, 22, and 26 lm,at mass percentage from 0 % to 50 % with an interval of10 %, respectively. Remote phosphor package was adopted and overall phosphor concentration was kept constant for better comparison. Moreover, absorption coefficient labs,scattering coefficient lscaand extinction coefficient lext of each hybrid phosphors were calculated based on Mie theory to further discuss the experiment results. Results show that, the introduction of small-particle-diameter phosphor to large one can highly improve angular color uniformity while only slightly reduce light efficacy. The optimal performance with angular color uniformity of91.6 % as well as normalized light efficacy of 95.7 % is achieved in the white light emitting diode with hybrid phosphors consisting of 60 wt% powder of 22 μm and40 wt% powder of 4 μm.
基金
financially supported by the National Natural Science Foundation of China (No. 51272027)