Open AccessEfficiency enhancement of quantum dot–phosphor hybrid white-light-emitting diodes using a centrifugation-based quasi-horizontal separation structure
Author(s) -
Zongtao Li,
Jialong Zheng,
Jiasheng Li,
Wanting Zhan
Publication year - 2020
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.392900
Subject(s) - phosphor , materials science , luminous flux , light emitting diode , diode , optics , optoelectronics , quantum dot , quantum efficiency , luminescence , physics , light source
In this paper, a centrifugation-based quasi-horizontal separation (c-HS) structure is proposed to enhance the QD light extraction of QD-phosphor hybrid white LEDs (WLEDs), effectively suppressing the backscattered loss from phosphor at the top region of the QD layer. Results indicate that a large centrifugation speed and dispensing mass of the QD layer is more beneficial to reducing the local density of phosphor at the top region, realizing quasi-horizontal separation between phosphor and QDs. Moreover, WLEDs with c-HS structure and conventional vertically layered packaging reference structure were compared at different correlated color temperatures (CCT). The radiant power and luminous flux achieved by the c-HS structure were 13.6% and 10.8%, respectively, higher than the reference structure at a typical warm white color of ∼4000 K. Consequently, this study can provide a new perspective on designing the separation structure for QD-phosphor hybrid WLEDs considering the backscattering loss of QD light.