量子点Wide Range Correlated Color Temperature Light Generation From Resonant Cavity Hybrid Quantum Dot Light-Emitting Diodes.pdfVIP

IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS, VOL. 21, NO. 4, JULY/AUGUST 2015 1900407 Wide-Range Correlated Color Temperature Light Generation From Resonant Cavity Hybrid Quantum Dot Light-Emitting Diodes Kuo-Ju Chen, Chien-Chung Lin, Senior Member, IEEE, Hau-Vei Han, Chia-Yu Lee, Shih-Hsuan Chien, Kuan-Yu Wang, Sheng-Huan Chiu, Zong-Yi Tu, Jie-Ru Li, Teng-Ming Chen, Xiuling Li, Min-Hsiung Shih, Member, IEEE, and Hao-Chung Kuo, Fellow, IEEE Abstract—This study presents extremely uniform colloidal low cost [5], [6]. These types of WLEDs have been commer- quantum dot white light-emitting diodes (QD-WLEDs) that cialized and YAG:Ce has already been developed as a down- demonstrate a high color rendering index (CRI) and correlated converting material; however, the problem of the instability of color temperatures (CCTs) ranging from 2500 to 4500 K. Ex- the color quality remains a critical challenge for phosphor based perimental results indicate that the structure of the distributed Bragg reflector (DBR) containing a stopband in the UV region WLEDs [7]. In general, the characteristics of WLEDs such as enhances the intensity output of both monochromatic QD-LEDs the homogenous correlated color temperature (CCT) and high and QD-WLEDs by reflecting the unconverted UV light back onto color rendering index (CRI) are considered the key factors that the package to excite the QDs further. Furthermore, the angular must be used in solid-state lighting (SSL). Therefore, several CCT uniformity of the QD-WLEDs also improved considerably studies have prop