Browsing by Author "Huang, Che-Hsuan"

Now showing 1 - 9 of 9

A high quality liquid-type quantum dot white light-emitting diode
(2016-01-01)
Sher, Chin-Wei
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Lin, Chin-Hao
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Lin, Huang-Yu
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Lin, Chien-Chung
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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
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Lin, Chih-Hao
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Lin, Huang-Yu
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Lin, Chien-Chung
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Huang, Che-Hsuan
CIGS solar cell integrated with high mobility microcrystalline Si TFTs on 30X40 cm(2) glass panels for self powered electronics
(2012-01-01)
Shen, Chang-Hong
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Shieh, Jia-Min
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Wu, Tsung-Ta
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Huang, Jung Y.
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Huang, Che-Hsuan
For the first time, we report a novel self-powered TFT panel (30X40cm(2)) by integration of sputtering/non-toxic Se vapor selenization copper-indium-gallium-selenide (CIGS) solar cell (conversion efficiency of 8%) and high electron-mobility (172 cm(2)/V-s) micro-crystalline (mu c)-Si TFTs.
High-efficiency and low assembly-dependent chip-scale package for white light-emitting diodes
(2015-04-21)
Huang, Che-Hsuan
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Chen, Kuo-Ju
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Tsai, Ming-Ta
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Shih, Min-Hsiung
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Sun, Chia-Wei
This article presents a chip-scale package (CSP) with conformal and uniform structures for white light-emitting diodes used in lighting and backlight unit (BLU) applications. The CSP structures produce higher light extraction efficiency and lower assembly-dependent packaging compared with conventional surface-mounted devices (SMDs). Simulation results show that compared with SMDs, the luminous efficiency of CSP structures is 8.81% higher in lighting applications and 9.43% higher in BLU applications. This is likely due to light loss in the light bowl of the SMDs. Moreover, CSPs with a conformal phosphor structure exhibit low assembly dependence and redundancy, and rb-CSPs with a conformal structure are a more effective light source in both lighting and BLU applications. (C) 2015 Society of Photo-Optical Instrumentation Engineers (SPIE)
Novel Method for Estimating Phosphor Conversion Efficiency of Light-Emitting Diodes
(2018-12-01)
Lin, Chih-Hao
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Huang, Che-Hsuan
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Pai, Yung-Min
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Lee, Chung-Fu
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Lin, Chien-Chung
This study presents a novel method for estimating the phosphor conversion efficiency of white light-emitting diodes (WLEDs) with different ratios of phosphors. Numerous attempts have been made for predicting the phosphor conversion efficiency of WLEDs using Monte Carlo ray tracing and the Mie scattering theory. However, because efficiency depends on the phosphor concentration, obtaining a tight match between this model and the experimental results remains a major challenge. An accurate prediction depends on various parameters, including particle size, morphology, and packaging process criteria. Therefore, we developed an efficient model that can successfully correlate the total absorption ratio to the phosphor concentration using a simple equation for estimating the spectra and lumen output. The novel and efficient method proposed here can accelerate WLED development by reducing costs and saving fabrication time.
Research on a Novel GaN-Based Converted Mini-LED Backlight Module via a Spectrum-Decouple System
(2020-01-01)
Huang, Che-Hsuan
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Chang, Shu Hsiu
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Liaw, Been-Yu
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Liu, Cheng-Yi
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Chou, Chia-Yueh
Owing to the development of modern display technology, micro- and mini-light-emitting diodes (LEDs) have affected technological advancements in the display industry. The structure of mini-LEDs is completely different than that of traditional LED backlights because the former employs a display technology with an LED array structure, optical resonant cavity, and color conversion layer. Display backlight technology encounters difficulty in achieving a truly effective energy-loss mechanism when designing or measuring mini-LED performance. The present study proposes three major mini-LED energy loss mechanisms: cross-talk, resonant, and quantum conversion losses. Herein, the spectrum was obtained through the integrating sphere system, and the calculation mechanism was formed by the down-conversion theorem as the decoupling principle, which successfully calculated the independent energy-loss efficiency of each mechanism and effectively deduced the brightness and color saturation performance of this design combination.
Spectral Model of Multiple-Layer of Hybrid Colloidal Quantum Dots for Light Emitting Diodes
(2017-01-01)
Huang, Che-Hsuan
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Hsu, Shun-Chieh
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Kee, Li-Ann
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Chung, Meng-Ting
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Chen, Teng-Ming
A semi-empirical model is developed to model the multiple-layer structure of hybrid colloidal quantum dots in light emitting diodes. The layer-sequence effect of the quantum dots matches with the measured data and the optimal condition is obtained.
The effect of free-standing GaN substrate on carrier localization in ultraviolet InGaN light-emitting diodes
(2014-12-13)
Tsai, Ming-Ta
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Chu, Chung-Ming
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Huang, Che-Hsuan
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Wu, Yin-Hao
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Chiu, Ching-Hsueh
In this study, we have grown 380-nm ultraviolet light-emitting diodes (UV-LEDs) based on InGaN/AlInGaN multiple quantum well (MQW) structures on free-standing GaN (FS-GaN) substrate by atmospheric pressure metal-organic chemical vapor deposition (AP-MOCVD), and investigated the relationship between carrier localization degree and FS-GaN. The micro-Raman shift peak mapping image shows low standard deviation (STD), indicating that the UV-LED epi-wafer of low curvature and MQWs of weak quantum-confined Stark effect (QCSE) were grown. High-resolution X-ray diffraction (HRXRD) analyses demonstrated high-order satellite peaks and clear fringes between them for the UV-LEDs grown on the FS-GaN substrate, from which the interface roughness (IRN) was estimated. The temperature-dependent photoluminescence (PL) measurement confirmed that the UV-LEDs grown on the FS-GaN substrate exhibited better carrier confinement. Besides, the high-resolution transmission electron microscopy (HRTEM) and energy-dispersive spectrometer (EDS) mapping images verified that the UV-LEDs on FS-GaN have fairly uniform distribution of indium and more ordered InGaN/AlInGaN MQW structure. Clearly, the FS-GaN can not only improve the light output power but also reduce the efficiency droop phenomenon at high injection current. Based on the results mentioned above, the FS-GaN can offer UV-LEDs based on InGaN/AlInGaN MQW structures with benefits, such as high crystal quality and small carrier localization degree, compared with the UV-LEDs on sapphire.
Ultra-High Light Extraction Efficiency and Ultra-Thin Mini-LED Solution by Freeform Surface Chip Scale Package Array
(2019-04-01)
Huang, Che-Hsuan
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Kang, Chieh-Yu
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Chang, Shu-Hsiu
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Lin, Chih-Hao
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Lin, Chun-Yu
In this study, we present a novel type of package, freeform-designed chip scale package (FDCSP), which has ultra-high light extraction efficiency and bat-wing light field. For the backlight application, mainstream solutions are chip-scale package (CSP) and surface-mount device package (SMD). Comparing with these two mainstream types of package, the light extraction efficiency of CSP, SMD, and FDCSP are 88%, 60%, and 96%, respectively. In addition to ultra-high light extraction efficiency, because of the 160-degree bat-wing light field, FDCSP could provide a thinner and low power consumption mini-LED solution with a smaller number of LEDs than CSP and SMD light source array.