Browsing by Author "Wang, Kuan-Yu"

Now showing 1 - 4 of 4

A high quality liquid-type quantum dot white light-emitting diode
(2016-01-01)
Sher, Chin-Wei
;
Lin, Chin-Hao
;
Lin, Huang-Yu
;
Lin, Chien-Chung
;
Huang, Che-Hsuan
This study demonstrates a novel package design to store colloidal quantum dots in liquid format and integrate them with a standard LED. The high efficiency and high quality color performance at a neutral white correlated color temperature is demonstrated. The experimental results indicate that the liquid-type quantum dot white light-emitting diode (LQD WLED) is highly efficient and reliable. The luminous efficiency and color rendering index (CRI) of the LQD WLED can reach 271 lm W-op(-1) and 95, respectively. Moreover, a glass box is employed to prevent humidity and oxygen erosion. With this encapsulation design, our quantum dot box can survive over 1000 hours of storage time.
A high quality liquid-type quantum dot white light-emitting diode (vol 8, pg 1117, 2016)
(2018-04-07)
Sher, Chin-Wei
;
Lin, Chih-Hao
;
Lin, Huang-Yu
;
Lin, Chien-Chung
;
Huang, Che-Hsuan
Improvement of light quality by DBR structure in white LED
(2015-02-09)
Lin, Huang-Yu
;
Chen, Kuo-Ju
;
Wang, Sheng-Wen
;
Lin, Chien-Chung
;
Wang, Kuan-Yu
This study demonstrates the application of DBR structure into the remote phosphor structure to improve the angular correlated color temperature (CCT) deviation in white light-emitting diodes (WLEDs). In the experiment, the LED device with DBR structure yielded a higher luminous efficiency than a conventional structure. The CCT deviation can be improved from 1758K to 280K in a range of -70 to 70 degree and the luminous flux increases more than 10% due to the enhancement of the light extraction of the blue light. Moreover, the reflectance of the different DBR structures is analyzed with different angles to reveal the reasons of such improvements. As the result, this LED device with DBR structure shows the great potential to use as the next generation lighting source. (C) 2014 Optical Society of America
Wide-Range Correlated Color Temperature Light Generation From Resonant Cavity Hybrid Quantum Dot Light-Emitting Diodes
(2015-07-01)
Chen, Kuo-Ju
;
Lin, Chien-Chung
;
Han, Hau-Vei
;
Lee, Chia-Yu
;
Chien, Shih-Hsuan
This study presents extremely uniform colloidal quantum dot white light-emitting diodes (QD-WLEDs) that demonstrate a high color rendering index (CRI) and correlated color temperatures (CCTs) ranging from 2500 to 4500 K. Experimental results indicate that the structure of the distributed Bragg reflector (DBR) containing a stopband in the UV region enhances the intensity output of both monochromatic QD-LEDs and QD-WLEDs by reflecting the unconverted UV light back onto the package to excite the QDs further. Furthermore, the angular CCT uniformity of the QD-WLEDs also improved considerably because of the dependence of the DBR structure on the incident angle. The angular CCT deviation in the range of -70 degrees to 70 degrees decreased to 39 K and the CRI of the WLED is higher than 90. The high-CRI and uniform angular CCT QD-WLED containing the DBR demonstrates potential applicability as the lighting source of next-generation display devices and solid-state lighting.