scholarly journals Efficient ITO-free Down-conversion White OLEDs with a Good Color Rendering Property

2012 ◽  
Author(s):  
Seunghyup Yoo
Keyword(s):  
White Oleds ◽  
Color Rendering ◽  
Down Conversion

scholarly journals Improving color rendering index of top-emitting white OLEDs with single emitter by using microcavity effects

2022 ◽  
Vol 100 ◽  
pp. 106381
Author(s):  
Minqiang Wan ◽  
Wenqing Zhu ◽  
Lu Huang ◽  
Yunping Zhao ◽  
Zixing Wang ◽  
...  
Keyword(s):  
Color Rendering Index ◽  
Single Emitter ◽  
White Oleds ◽  
Color Rendering

scholarly journals Chromaticity Study of Curcumin Dye Extracted from Curcuma longa L. Using for UV Light down Conversion for White Light Emitting Diode

2019 ◽  
Vol 290 ◽  
pp. 183-189
Author(s):  
Mahmood Al Shafouri ◽  
Naser Mahmoud Ahmed ◽  
Zainuriah Hassan ◽  
Munirah Abdullah Almessiere
Keyword(s):  
White Light ◽  
Uv Light ◽  
Light Emitting Diode ◽  
Curcuma Longa ◽  
Color Temperature ◽  
Light Emitting ◽  
Chromaticity Coordinates ◽  
Major Factors ◽  
Color Rendering ◽  
Down Conversion

In thus study, Turmeric phosphor dye was extracted from Curcuma Longa L. via a simple technique using silica gel. The phosphor was used for light down-conversion of UV light for the manufacture white light emitting diode (WLED). The UV-LED was analyzed over 395nm wavelengths. The characteristics of the white light chromaticity were controlled by tuning the current and phosphor concentration. An optimum color rendering index (CRI) value of 63.4 was obtained. The chromaticity coordinates (CIE) and correlated color temperature (CCT) were measured for various currents and phosphor concentrations. The white phosphor exhibited CIE value of 0.355,0.338 and CCT of 4567 K. The concentration of phosphor and amount of applied current were confirmed to be major factors that control the intensity of white light emitted from the sample, where CIE and CRI of the emitted light steadily increased with the concentration of phosphor and current. Thus, phosphor concentration has a critical effect on conversion efficiency. Key words: Turmeric, phosphor, WLED, curcumin

Efficient phosphorescent white OLEDs with high color rendering capability

2010 ◽  
Vol 11 (3) ◽  
pp. 412-418 ◽  
Author(s):  
Chih-Hao Chang ◽  
Kun-Cheng Tien ◽  
Chung-Chia Chen ◽  
Ming-Shiang Lin ◽  
Hsing-Chieh Cheng ◽  
...  
Keyword(s):  
White Oleds ◽  
Color Rendering

DOWN-CONVERSION WHITE OLEDS: Down-Conversion White Organic Light-Emitting Diodes Using Microcavity Structure (Adv. Energy Mater. 2/2011)

2011 ◽  
Vol 1 (2) ◽  
pp. 173-173
Author(s):  
Jaewon Lee ◽  
Neetu Chopra ◽  
Debasis Bera ◽  
Sergey Maslov ◽  
Sang-Hyun Eom ◽  
...  
Keyword(s):  
Light Emitting Diodes ◽  
Organic Light Emitting Diodes ◽  
Light Emitting ◽  
Organic Light ◽  
White Oleds ◽  
Down Conversion ◽  
Energy Mater

Phosphorescent White OLEDs for Solid-state Lighting

2009 ◽  
Vol 1212 ◽  
Author(s):  
Sean Xia ◽  
Peter Levermore ◽  
Vadim Adamovich ◽  
Chun Lin ◽  
Raymond C. Kwong ◽  
...  
Keyword(s):  
Energy Transfer ◽  
Solid State ◽  
Energy Efficient ◽  
High Efficiency ◽  
Solid State Lighting ◽  
Energy Star ◽  
Lighting Industry ◽  
Partial Energy ◽  
White Oleds ◽  
Color Rendering

AbstractWhite OLEDs (WOLEDTMs) fabricated using energy efficient phosphorescent OLED (PHOLEDTM) technology open up exciting new ways to develop efficient white lighting. WOLEDs have the potential to transform the lighting industry. In this presentation, phosphorescent WOLEDs with high conductivity transport layers will be discussed. White light can be generated by partial energy transfer from blue to green and red. Single WOLED stacks are demonstrated that match the Energy Star® lighting color criteria for 2700K and 3000K with high efficiency (˜80 lm/W) and high color rendering indices (˜80). Both devices had operational lifetimes (LT70%) over 30,000 hours measured from an initial luminance of 1,000 cd/m2. Different techniques to improve optical outcoupling will also be discussed.

scholarly journals Chromaticity Properties of Curcuminoids Dye Nanofibers Prepared by Electrospinning for White Light Down-Conversion

2020 ◽  
Vol 301 ◽  
pp. 77-84
Author(s):  
M. Al Shafouri ◽  
Naser Mahmoud Ahmed ◽  
Zainuriah Hassan ◽  
Munirah Abdullah Almessiere
Keyword(s):  
Methyl Methacrylate ◽  
White Light ◽  
Light Emitting Diode ◽  
Curcuma Longa ◽  
Average Diameter ◽  
Color Temperature ◽  
Light Emitting ◽  
Poly Methyl Methacrylate ◽  
Color Rendering ◽  
Down Conversion

In this study, the chromaticity properties of curcuminoids nanofibers were studied. Recent studies revealed that the nature of emitted light from curcuminoids and the poor stability which limits their illumination applications can be further improved using nanofibers and nanoparticles of curcuminoids. Motivated by this idea, we prepared some Poly(methyl methacrylate) (PMMA) integrated curcuminoids nanofibers via electrospinning. Poly(methyl methacrylate) (PMMA) were used in three types of concentration (5,10 and15wt%) which were mixed with (curcuma longa L.) powder to produce curcuminoids solution by using the centrifuge to separate the curcuminoids solution from the impurities. Different amounts of polymer solution mixed with curcuminoids (1 to 5ml) were spun by electrospinning to study its properties. The effect of annealing on samples was studied. The chromatic study of the samples and the effect of the amount and concentration of the solution were studied by pumping the samples in three different light emitting diode (LED) wavelengths (365, 390 and 445nm). The white light chromaticity coordinates (CIE), correlated color temperature (CCT) and color rendering index (CRI) were measured. The optimum CIE, CRI and CCT values of (X= 0.3051; Y= 0.3370), 64 and 6809K, respectively were obtained. By using field emission scanning electron microscope (FESEM) device, the curcuminoids nanofibers diameter was measured, where the values obtained ranged between 191 to 234nm. After the annealing process, curcuminoids nanoparticles average diameter 13-19 nm were obtained.

scholarly journals Fluorescent white OLEDs with a high color‐rendering index using a silicon‐cored anthracene derivative as a blue host

2010 ◽  
Vol 11 (3) ◽  
pp. 123-127
Author(s):  
Jeonghun Kwak ◽  
Yi‐Yeol Lyu ◽  
Hyunkoo Lee ◽  
Kookheon Char ◽  
Changhee Lee
Keyword(s):  
Anthracene Derivative ◽  
Color Rendering Index ◽  
White Oleds ◽  
Color Rendering
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