Full-Color Fluorescent Display Devices Using a Near-UV Light-Emitting Diode

1996 ◽  
Vol 35 (Part 2, No. 7A) ◽  
pp. L838-L839 ◽  
Author(s):  
Yuichi Sato ◽  
Nobuyuki Takahashi ◽  
Susumu Sato
1998 ◽  
Vol 37 (Part 2, No. 2A) ◽  
pp. L129-L131 ◽  
Author(s):  
Yuichi Sato ◽  
Nobuyuki Takahashi ◽  
Susumu Sato

2016 ◽  
Vol 697 ◽  
pp. 727-732 ◽  
Author(s):  
Bo Cui ◽  
Qing Hong Zhang ◽  
Hong Zhi Wang ◽  
Yao Gang Li

A new kind of Ca4Si2O7F2:Ce3+, Tb3+, Sm3+ oxyfluoride phosphor micron belt mat was obatained by simply electrospinning process and subsequent heat treatment. XRD result shows that a pure Ca4Si2O7F2 phase can be obtained at low temperature of around 900 °C. The micron belt precursor has a smooth surface and uniform morphology, and the width and thickness of the belt is about 2 μm and 200 nm. The morphology of micron belt is well retained after heat treatment, forming a plat phosphor mat consisting of uniform micron belt network. Ca4Si2O7F2:Ce3+, Ca4Si2O7F2:Tb3+, and Ca4Si2O7F2:Sm3+ exhibit the characteristic emissions of Ce3+ (4f7→4f65d1, blue), Tb3+ (4f8→4f75d, green), and Sm3+ (4f6→4f65d, red) under the excitation of near-UV light, respectively. By adjusting the doping concentration of Ce3+, Tb3+, Sm3+ ions a white emission in a single phase was obtained under the excitation of 360 nm. We have demonstrated that Ca4Si2O7F2:Ce3+, Tb3+, Sm3+ phosphor mat can be a promising candidate for a color-tunable phosphor mat applied in a near-UV White light emitting diodes.


Author(s):  
Xuyong Yang ◽  
Evren Mutlugun ◽  
Yuan Gao ◽  
Yongbiao Zhao ◽  
Swee Tiam Tan ◽  
...  

2018 ◽  
Vol 49 ◽  
pp. 267-270 ◽  
Author(s):  
CHIH-HAO LIN ◽  
CHUN-FU LEE ◽  
CHIEN-CHUNG LIN ◽  
CHEN-HSIEN CHU ◽  
CHIN-WEI SHER ◽  
...  

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Fumiya Osawa ◽  
Kazuhiro Marumoto

Abstract Spin-states and charge-trappings in blue organic light-emitting diodes (OLEDs) are important issues for developing high-device-performance application such as full-color displays and white illumination. However, they have not yet been completely clarified because of the lack of a study from a microscopic viewpoint. Here, we report operando electron spin resonance (ESR) spectroscopy to investigate the spin-states and charge-trappings in organic semiconductor materials used for blue OLEDs such as a blue light-emitting material 1-bis(2-naphthyl)anthracene (ADN) using metal–insulator–semiconductor (MIS) diodes, hole or electron only devices, and blue OLEDs from the microscopic viewpoint. We have clarified spin-states of electrically accumulated holes and electrons and their charge-trappings in the MIS diodes at the molecular level by directly observing their electrically-induced ESR signals; the spin-states are well reproduced by density functional theory. In contrast to a green light-emitting material, the ADN radical anions largely accumulate in the film, which will cause the large degradation of the molecule and devices. The result will give deeper understanding of blue OLEDs and be useful for developing high-performance and durable devices.


2016 ◽  
Author(s):  
Renjie Wang ◽  
Yong-Ho Ra ◽  
Yuanpeng Wu ◽  
Songrui Zhao ◽  
Hieu P. T. Nguyen ◽  
...  

2019 ◽  
Vol 13 ◽  
pp. 102285 ◽  
Author(s):  
Chia-Yen Huang ◽  
Tsung-Yen Liu ◽  
Shih-Ming Huang ◽  
Kai-Hsiang Chang ◽  
Tsu-Ying Tai ◽  
...  

2019 ◽  
Vol 290 ◽  
pp. 183-189
Author(s):  
Mahmood Al Shafouri ◽  
Naser Mahmoud Ahmed ◽  
Zainuriah Hassan ◽  
Munirah Abdullah Almessiere

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


ACS Omega ◽  
2018 ◽  
Vol 3 (10) ◽  
pp. 13798-13807 ◽  
Author(s):  
You-Ting Tsai ◽  
Shoou-Jinn Chang ◽  
Liang-Wen Ji ◽  
Yu-Jen Hsiao ◽  
I-Tseng Tang ◽  
...  

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