scholarly journals Na3Ce(PO4)2:Tb3+ and Na(Mg2–xMnX)LiSi4O10F2:Mn phosphors: a suitable selection for enhancing color quality and luminous flux of remote white light-emitting diodes

2020 ◽  
Vol 18 (4) ◽  
pp. 2095
Author(s):  
Nguyen Thi Phuong Loan ◽  
Nguyen Doan Quoc Anh
Keyword(s):  
White Light ◽  
Light Emitting Diodes ◽  
Luminous Flux ◽  
Light Emitting ◽  
Color Quality ◽  
Selection For ◽  
White Light Emitting Diodes

scholarly journals (Y,Gd)BO3:Eu red phosphor for dual-layer phosphor structure to enhance the optical performance of white light-emitting diodes

2021 ◽  
Vol 10 (4) ◽  
pp. 1930-1935
Author(s):  
Phan Xuan Le ◽  
Le Hung Tien
Keyword(s):  
White Light ◽  
Light Emitting Diodes ◽  
Red Light ◽  
Phosphor Layer ◽  
Light Emitting ◽  
Conformal Coating ◽  
Color Quality ◽  
Remote Phosphor ◽  
White Light Emitting Diodes ◽  
Color Rendering

Among the structures using for fabricating white light-emitting diodes (WLEDs) such as the conformal coating or in-cup geometries, the remote phosphor structure gives the highest luminous efficacy. However, in terms of color quality, its performance is not as good as the others. The red-light compensation has been reported as the effective solution for enhancing the color quality of WLEDs. Hence, this study adopted the idea and applied to the dual-layer phosphor structure. The phosphor used to boost the red color in light formation is (Y,Gd)BO3:Eu particle. The dual-layer remote phosphor structure was simulated with the red (Y,Gd)BO3:Eu phosphor layer above the original yellow phosphor YAG:Ce3+ one. The WLEDs with different correlated color temperatures of 5600 K, 6600 K and 7700K were experimented. Mie-theory and Lambert-Beer law were applied to examine the results. The growth in color rendering index (CRI) and color quality scale (CQS) with the increase of (Y,Gd)BO3:Eu phosphor concentration was observed. Nevertheless, the lumen efficacy would be degraded if the concentration was over a certain number. The information provided in this article is useful for the development of high-power WLED production with greater color quality.

scholarly journals Mining Unexplored Chemistries for Phosphors for High-Color-Quality White-Light-Emitting Diodes

Joule ◽  
2018 ◽  
Vol 2 (5) ◽  
pp. 914-926 ◽  
Author(s):  
Zhenbin Wang ◽  
Jungmin Ha ◽  
Yoon Hwa Kim ◽  
Won Bin Im ◽  
Joanna McKittrick ◽  
...  
Keyword(s):  
White Light ◽  
Light Emitting Diodes ◽  
Light Emitting ◽  
Color Quality ◽  
White Light Emitting Diodes

Synthesis of narrow-band red-emitting K2SiF6:Mn4+ phosphors for a deep red monochromatic LED and ultrahigh color quality warm-white LEDs

2015 ◽  
Vol 3 (3) ◽  
pp. 607-615 ◽  
Author(s):  
Ji Hye Oh ◽  
Heejoon Kang ◽  
Yun Jae Eo ◽  
Hoo Keun Park ◽  
Young Rag Do
Keyword(s):  
White Light ◽  
Light Emitting Diodes ◽  
Narrow Band ◽  
Light Emitting ◽  
White Leds ◽  
Color Quality ◽  
Warm White Light ◽  
White Light Emitting Diodes

In this study, we synthesized and characterized narrow-band red-emitting K2SiF6:Mn4+ phosphors in order to improve the color qualities of warm white light-emitting diodes (LEDs).

Excellent Color Quality of White-Light-Emitting Diodes by Embedding Quantum Dots in Polymers Material

2016 ◽  
Vol 22 (1) ◽  
pp. 35-41 ◽  
Author(s):  
Huang-Yu Lin ◽  
Sheng-Wen Wang ◽  
Chien-Chung Lin ◽  
Kuo-Ju Chen ◽  
Hau-Vei Han ◽  
...  
Keyword(s):  
Quantum Dots ◽  
White Light ◽  
Light Emitting Diodes ◽  
Light Emitting ◽  
Color Quality ◽  
White Light Emitting Diodes ◽  
Excellent Color

The characteristic analysis of continuous light diodes

2021 ◽  
pp. 2150247
Author(s):  
I. T. Huseynov
Keyword(s):  
White Light ◽  
Light Emitting Diodes ◽  
Light Flux ◽  
Continuous Light ◽  
Luminous Flux ◽  
Characteristic Analysis ◽  
Light Emitting ◽  
White Leds ◽  
Composite Solution ◽  
White Light Emitting Diodes

Photoluminescence (PL) spectra, light flux, color temperatures and color coordinates of white light emitting diodes that are based on CaGa2S4:Eu[Formula: see text]–CaS:Eu[Formula: see text] composite solution and industrial phosphor were analyzed. The study was carried out continuously for a 1000 h with two white LEDs which based on an exciting InGaN wavelength of 450 nm with a power of 10 W. Luminous flux and color temperatures were investigated during 200, 400, 600, 800 and 1000 h. All experiments were carried out for both CaGa2S4:Eu[Formula: see text]–CaS:Eu[Formula: see text] and industrial phosphor and comparatively analyzed. Consequently, the application perspectives of CaGa2S4:Eu[Formula: see text]–CaS:Eu[Formula: see text] composite solution in the white LEDs technologies are presented.

Optimization Spectrum of White Light Emitting Diodes Based on Correlated Color Temperature and Luminous Flux

2015 ◽  
Vol 44 (10) ◽  
pp. 1030001
Author(s):  
黄马连 HUANG Ma-lian ◽  
陈焕庭 CHEN Huan-ting ◽  
周小方 ZHOU Xiao-fang ◽  
蔡嘉毅 CAI Jia-yi ◽  
周锦荣 ZHOU Jin-rong ◽  
...  
Keyword(s):  
White Light ◽  
Light Emitting Diodes ◽  
Luminous Flux ◽  
Color Temperature ◽  
Light Emitting ◽  
White Light Emitting Diodes

scholarly journals Excellent Luminous Efficacy and Color Homogeneity of White Light-Emitting Diodes with YPO4:Ce3+:Tb3+ Phosphor

2018 ◽  
Vol 72 ◽  
pp. 02002
Author(s):  
Vo Phu Thoai ◽  
Nguyen Doan Quoc Anh
Keyword(s):  
White Light ◽  
Light Emitting Diodes ◽  
White Led ◽  
Gradual Decline ◽  
Luminous Efficacy ◽  
Light Emitting ◽  
Color Quality ◽  
Quality Scale ◽  
Color Uniformity ◽  
White Light Emitting Diodes

In this paper, we focus on researching the method, which the color homogeneity and the lumen output of multi-chip white LED lamps (MCW-LEDs) need to support for increasing the efficiency. The successful results can be achieved by mixing the green YPO4:Ce3+:Tb3+ phosphor with their phosphor compounding. Through experiment results, we assert that the MCW-LEDs can achieve the significant consequence in performance by following that method and it is also again confirmed that when the concentration of YPO4:Ce3+:Tb3+ has tendency to increase, which impulse the development of the color uniformity and the luminous efficacy of MCW-LEDs with average correlated color temperatures (CCT) of 8500 K, while the color quality scale shows signs of gradual decline. It is not difficult to gain incredible presentation of MCW-LEDs if we are clever in choosing the suitable concentration and size of YPO4:Ce3+:Tb3+.

scholarly journals Improving Color Quality of Nanowire White Light-Emitting Diodes with Mn4+ Doped Fluoride Nanosheets

Micromachines ◽  
2021 ◽  
Vol 12 (8) ◽  
pp. 965
Author(s):  
Thi Hong Quan Vu ◽  
Thi Tuyet Doan ◽  
Barsha Jain ◽  
Ravi Teja Velpula ◽  
Tung Cao Thanh Pham ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
White Light ◽  
Light Emitting Diodes ◽  
Sodium Dodecyl ◽  
Color Temperature ◽  
Excellent Thermal Stability ◽  
Light Emitting ◽  
Color Quality ◽  
White Light Emitting Diodes ◽  
Red Emitting Phosphor

A two-dimensional nanostructured fluoride red-emitting phosphor with an excellent quantum yield of ~91% is studied for cost-effective and high-color quality nanowire white light-emitting diodes (WLEDs). K2TiF6:Mn4+ phosphors are synthesized via an emulsification method using surfactants as sodium dodecyl sulphonate and oleic acid. The K2TiF6:Mn4+ phosphors in ultra-thin and nanosheet crystals are observed via scanning electron microscopy and high-resolution transmission electron microscopy. The surfactants are found to play a key role in inhibition of KTFM crystal growth process and stabilization of Mn4+ ions doping into the K2TiF6 host. The prepared phosphors exhibited intensive red emission at approximately 632 nm and excellent thermal stability in the range of 300 K–500 K upon 460 nm light excitation. Moreover, the K2TiF6:Mn4+ nanosheets were integrated on InGaN/AlGaN nanowire WLEDs for color quality study. The results show that the nanowire WLEDs with red-emitting phosphor exhibit unprecedentedly high color rendering index ~96.4, and correlated color temperature ~4450 K.

Sign in / Sign up

Export Citation Format

Share Document