scholarly journals Recent progress in red light-emitting diodes by III-nitride materials

2021 ◽  
Author(s):  
Daisuke Iida ◽  
Kazuhiro Ohkawa
Keyword(s):  
Recent Progress ◽  
Light Emitting Diodes ◽  
Red Light ◽  
Strain Engineering ◽  
Research Field ◽  
Material System ◽  
Light Emitting ◽  
Light Emitting Devices ◽  
Highly Efficient ◽  
Red Leds

Abstract GaN-based light-emitting devices have the potential to realize all visible emissions with the same material system. These emitters are expected to be next-generation RGB displays and illumination tools. These emitting devices have been realized with highly efficient blue and green light-emitting diodes (LEDs) and laser diodes (LDs). Extending them to longer wavelength emissions remains challenging from an efficiency perspective. In the emerging research field of micro-LED displays, III-nitride red LEDs are in high demand to establish highly efficient devices like conventional blue and green systems. In this review, we describe fundamental issues in the development of red LEDs by III-nitrides. We also focus on the key role of growth techniques such as higher temperature growth, strain engineering, nanostructures, and Eu doping. The recent progress and prospect of developing III-nitride-based red light-emitting devices will be presented.

Recent progress on defect modulation for highly efficient metal halide perovskite light-emitting diodes

2021 ◽  
Vol 22 ◽  
pp. 100946
Author(s):  
Le Ma ◽  
Boning Han ◽  
Fengjuan Zhang ◽  
Leimeng Xu ◽  
Tao Fang ◽  
...  
Keyword(s):  
Recent Progress ◽  
Light Emitting Diodes ◽  
Metal Halide ◽  
Light Emitting ◽  
Highly Efficient ◽  
Metal Halide Perovskite ◽  
Halide Perovskite

(K0.5Na0.5)NbO3:Eu3+/Bi3+: a novel, highly efficient, red light-emitting material with superior water resistance behavior

RSC Advances ◽  
2015 ◽  
Vol 5 (6) ◽  
pp. 4707-4715 ◽  
Author(s):  
Qiwei Zhang ◽  
Haiqin Sun ◽  
Tao Kuang ◽  
Ruiguang Xing ◽  
Xihong Hao
Keyword(s):  
Blue Light ◽  
White Light ◽  
High Performance ◽  
Water Resistance ◽  
Light Emitting Diodes ◽  
Red Light ◽  
Light Emitting ◽  
Highly Efficient ◽  
White Light Emitting Diodes

Materials emitting red light (∼611 nm) under excitation with blue light (440–470 nm) are highly desired for fabricating high-performance white light-emitting diodes (LEDs).

Multifunctional emitters for efficient simplified non-doped blueish green organic light emitting devices with extremely low efficiency roll-off

2017 ◽  
Vol 5 (26) ◽  
pp. 6527-6536 ◽  
Author(s):  
Amjad Islam ◽  
Dongdong Zhang ◽  
Xinhua Ouyang ◽  
Rongjuan Yang ◽  
Tao Lei ◽  
...  
Keyword(s):  
Light Emitting Diodes ◽  
Scientific Research ◽  
Industrial Applications ◽  
Organic Light Emitting Diodes ◽  
Light Emitting ◽  
Light Emitting Devices ◽  
Highly Efficient ◽  
Organic Light ◽  
Device Structures ◽  
Low Efficiency

Highly efficient organic light-emitting diodes (OLEDs) with simplified device structures are widely desired for both scientific research and industrial applications.

scholarly journals Specific Light-Emitting Diodes Can Suppress Sporulation of Podosphaera pannosa on Greenhouse Roses

Plant Disease ◽  
2010 ◽  
Vol 94 (9) ◽  
pp. 1105-1110 ◽  
Author(s):  
A. Suthaparan ◽  
S. Torre ◽  
A. Stensvand ◽  
M. L. Herrero ◽  
R. I. Pettersen ◽  
...  
Keyword(s):  
Wind Tunnel ◽  
White Light ◽  
Light Emitting Diodes ◽  
Dark Period ◽  
Red Light ◽  
Suppressive Effect ◽  
Continuous Illumination ◽  
Light Emitting ◽  
Dark Interval ◽  
Red Leds

When rose plants bearing colonies of Podosphaera pannosa were placed in a wind tunnel, the number of conidia trapped was directly proportional to intensity of daylight-balanced (white) light from 5 to 150 μmol m–2 s–1. Illumination of samples using blue (420 to 520 nm) light-emitting diodes (LEDs) increased the number of conidia trapped by a factor of approximately 2.7 over white light but germination of conidia under blue light was reduced by approximately 16.5% compared with conidia germination under white light. The number of conidia trapped under far-red (>685 nm) LEDs was approximately 4.7 times higher than in white light, and 13.3 times higher than under red (575 to 675 nm) LEDs, and germination was not induced compared with white light. When mildewed plants were exposed to cycles of 18 h of white light followed by 6 h of blue, red, far-red light, or darkness, light from the red LEDs reduced the number of conidia trapped by approximately 88% compared with darkness or far-red light. Interrupting the above dark period with 1 h of light from red LEDs also reduced the number of conidia trapped, while a 1-h period of light from far-red following the 1 h of light from red LEDs nullified the suppressive effect of red light. Our results indicate that brief exposure to red light during the dark interval may be as effective as continuous illumination in suppressing powdery mildew in greenhouse rose plant (Rosa × hybrida).

scholarly journals Synthesis and properties of hyperbranched polymers for white polymer light-emitting diodes

RSC Advances ◽  
2019 ◽  
Vol 9 (62) ◽  
pp. 36058-36065 ◽  
Author(s):  
Xuefeng Li ◽  
Haocheng Zhao ◽  
Long Gao ◽  
Xiaoling Xie ◽  
Weixuan Zhang ◽  
...  
Keyword(s):  
Light Emitting Diodes ◽  
Three Dimensional ◽  
Hyperbranched Polymers ◽  
Light Emitting ◽  
Light Emitting Devices ◽  
Highly Efficient ◽  
Polymer Light Emitting Diodes ◽  
Polymer Light Emitting Devices ◽  
Hyperbranched Structure

A potential hyperbranched structure with fluorene-alt-carbazole branches, a three-dimensional-structured SDF core and red Ir(piq)2acac light adjusting units is synthesized for using in highly efficient white polymer light-emitting devices.

Stress engineering for reducing the injection current induced blue shift in InGaN-based red light-emitting diodes

CrystEngComm ◽  
2021 ◽  
Author(s):  
Weizhen Yao ◽  
Lianshan Wang ◽  
Yulin Meng ◽  
Shaoyan Yang ◽  
Xianglin Liu ◽  
...  
Keyword(s):  
Sapphire Substrate ◽  
Light Emitting Diodes ◽  
Red Light ◽  
Blue Shift ◽  
Ingan Layer ◽  
Patterned Sapphire Substrate ◽  
Light Emitting ◽  
Stress Engineering ◽  
Engineering Strategy ◽  
Red Leds

Red LEDs with a small blue shift are fabricated by using a stress engineering strategy through the growth of the pre-stained InGaN layer and dual-wavelength QWs on a cone-shape patterned sapphire substrate.

scholarly journals Growth, Nutritional Quality, and Energy Use Efficiency of Hydroponic Lettuce as Influenced by Daily Light Integrals Exposed to White versus White Plus Red Light-emitting Diodes

HortScience ◽  
2019 ◽  
Vol 54 (10) ◽  
pp. 1737-1744 ◽  
Author(s):  
Zhengnan Yan ◽  
Dongxian He ◽  
Genhua Niu ◽  
Qing Zhou ◽  
Yinghua Qu
Keyword(s):  
Nutritional Quality ◽  
Energy Use ◽  
Light Emitting Diodes ◽  
Red Light ◽  
Dry Weight ◽  
Light Emitting ◽  
Energy Use Efficiency ◽  
White Leds ◽  
Use Efficiency ◽  
Red Leds

Few researchers examined different red light amounts added in white light-emitting diodes (LEDs) with varied daily light integrals (DLIs) for hydroponic lettuce (Lactuca sativa L.). In this study, effects of DLI and LED light quality (LQ) on growth, nutritional quality, and energy use efficiency of hydroponic lettuce were investigated in a plant factory with artificial lighting (PFAL). Hydroponic lettuce plants (cv. Ziwei) were grown for 20 days under 20 combinations of five levels of DLIs at 5.04, 7.56, 10.08, 12.60, and 15.12 mol·m−2·d−1 and four LQs: two kinds of white LEDs with red to blue ratio (R:B ratio) of 0.9 and 1.8, and two white LEDs plus red chips with R:B ratio of 2.7 and 3.6, respectively. Results showed that leaf and root weights and power consumption based on fresh and dry weights increased linearly with increasing DLI, and light and electrical energy use efficiency (LUE and EUE) decreased linearly as DLI increased. However, no statistically significant differences were found in leaf fresh and dry weights and nitrate and vitamin C contents between DLI at 12.60 and 15.12 mol·m−2·d−1. Also, no effects of LQ on leaf dry weight of hydroponic lettuce were observed at a DLI of 5.04 mol·m−2·d−1. White plus red LEDs with an R:B ratio of 2.7 resulted in higher leaf fresh weight than the two white LEDs. LUE increased by more than 20% when red light fraction increased from 24.2% to 48.6%. In summary, white plus red LEDs with an R:B ratio of 2.7 at DLI at 12.60 mol·m−2·d−1 were recommended for commercial hydroponic lettuce (cv. Ziwei) production in PFALs.

scholarly journals Growth and Carbohydrate Metabolism of Wheat Plants Grown with Red-light Emitting Diodes

HortScience ◽  
1995 ◽  
Vol 30 (4) ◽  
pp. 863C-863
Author(s):  
N.C. Yorio ◽  
M. Sanwo ◽  
C.S. Brown
Keyword(s):  
Light Emitting Diodes ◽  
Starch Content ◽  
Red Light ◽  
Fold Increase ◽  
Sucrose Phosphate Synthase ◽  
Small Mass ◽  
Fluorescent Light ◽  
Light Emitting ◽  
Carbohydrate Concentration ◽  
Red Leds

Light-emitting diodes (LEDs) are a potential light source for growing plants in space flight systems because of their superior safety and reliability, small mass and volume, electrical efficiency, and longevity. To determine the influence of narrow-spectrum LEDs on plant growth and metabolism, wheat (Triticum aestivum L. `Superdwarf') plants were grown under red LEDs (peak emission 660 nm) and compared to plants grown under daylight fluorescent, red LEDs + 1% blue fluorescent light (BL), and red LEDs + 10% BL. Plants were taller, had longer flag leaves, and delayed seed development when grown under red LEDs or red LEDs + 1% BL compared to those grown with 10% BL or under daylight fluorescent. Viable seeds (290% germination) were produced in all plants regardless of the light treatment. Total dry matter (DM), head DM, and seed DM were similar in the plants grown under the four light regimes, and there were no differences in the starch content of the seeds. Starch levels were 4-times greater and sucrose levels were 2.5-times greater in leaves of plants grown under the red LEDs compared to daylight fluorescent. Daylight fluorescent leaves showed a 1.8-fold increase in sucrose phosphate synthase (SPS) activity, a regulatory enzyme of sucrose synthesis. These results indicate that wheat can be grown successfully under red LEDs, but there are differences in carbohydrate concentration and metabolism in photosynthetic tissue.

scholarly journals The theory of thermally activated delayed fluorescence for organic light emitting diodes

2018 ◽  
Vol 54 (32) ◽  
pp. 3926-3935 ◽  
Author(s):  
T. J. Penfold ◽  
F. B. Dias ◽  
A. P. Monkman
Keyword(s):  
Recent Progress ◽  
Organic Molecules ◽  
Light Emitting Diodes ◽  
Delayed Fluorescence ◽  
Organic Light Emitting Diodes ◽  
Thermally Activated Delayed Fluorescence ◽  
Light Emitting ◽  
Thermally Activated ◽  
Highly Efficient ◽  
Organic Light

The recent progress in the theory of organic molecules exhibiting thermally activated delayed fluorescence (TADF) is discussed with a particular focus upon their application in highly efficient purely organic light emitting diodes (OLEDs).

scholarly journals HIGHLY EFFICIENT RED LIGHT-EMITTING DIODES BASED ON SILOLE-CONTAINING POLYCARBAZOLE

2009 ◽  
Vol 009 (9) ◽  
pp. 845-851 ◽  
Author(s):  
Zhitian LIU ◽  
Jianhua ZOU ◽  
Junwu CEHN ◽  
Yongqiang LIU ◽  
Junbiao PENG ◽  
...  
Keyword(s):  
Light Emitting Diodes ◽  
Red Light ◽  
Light Emitting ◽  
Highly Efficient
Sign in / Sign up

Export Citation Format

Share Document