Enhancement of angular CCT by hybrid phosphor structure in White Light-emitting Diodes

Abstract

The hybrid phosphor structure for white light-emitting diodes application was reported. It was demonstrated that the improvement of the luminous efficiency as well as the good uniform angular correlated color temperature (CCT) in hybrid phosphor structure compared with the conventional dispense method. The experimental results showed the CCT deviation was improved from 453K to 280K in the range of -70 to 70 degrees, which could be attributed to the large divergent angle of blue light. Moreover, the high lumen output was also achieved, as compared with dispense and conformal phosphor structures. Therefore, the experimental results indicated that the hybrid phosphor structure was feasible to use in the solid state lighting.