Metasurface integrated high energy efficient and high linearly polarized InGaN/GaN light emitting diode

Nanoscale ◽  
2017 ◽  
Vol 9 (26) ◽  
pp. 9104-9111 ◽  
Author(s):  
Miao Wang ◽  
Fuyang Xu ◽  
Yu Lin ◽  
Bing Cao ◽  
Linghua Chen ◽  
...  
Keyword(s):  
Energy Efficient ◽  
Light Emitting Diode ◽  
High Energy ◽  
Light Emitting ◽  
Linearly Polarized

scholarly journals LED Rail Signals: Full Hardware Realization of Apparatus with Independent Intensity by Temperature Changes

Electronics ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 1291
Author(s):  
Giuseppe Schirripa Schirripa Spagnolo ◽  
Fabio Leccese
Keyword(s):  
Temperature Sensor ◽  
Energy Efficient ◽  
Light Emitting Diode ◽  
Junction Temperature ◽  
Light Emitting ◽  
Temperature Changes ◽  
Wide Range ◽  
International Regulations ◽  
Long Lifetime ◽  
Set Up

Nowadays, signal lights are made using light-emitting diode arrays (LEDs). These devices are extremely energy efficient and have a very long lifetime. Unfortunately, especially for yellow/amber LEDs, the intensity of the light is closely related to the junction temperature. This makes it difficult to design signal lights to be used in naval, road, railway, and aeronautical sectors, capable of fully respecting national and international regulations. Furthermore, the limitations prescribed by the standards must be respected in a wide range of temperature variations. In other words, in the signaling apparatuses, a system that varies the light intensity emitted according to the operating temperature is useful/necessary. In this paper, we propose a simple and effective solution. In order to adjust the intensity of the light emitted by the LEDs, we use an LED identical to those used to emit light as a temperature sensor. The proposed system was created and tested in the laboratory. As the same device as the ones to be controlled is used as the temperature sensor, the system is very stable and easy to set up.

Opportunities and Challenges in Perovskite LEDs Commercialization

2021 ◽  
Author(s):  
Kai Zhang ◽  
Ningning Zhu ◽  
Mingming Zhang ◽  
Lei Wang ◽  
Jun Xing
Keyword(s):  
Energy Saving ◽  
Energy Efficient ◽  
Light Emitting Diode ◽  
Environment Friendly ◽  
Light Emitting ◽  
Lighting Technology

Recently, the light-emitting diode (LED) has been considered as an energy-saving and environment-friendly lighting technology，which is ten times more energy efficient than conventional incandescent lights. As an emerging photoelectric material,...

Light Emitting Diode Technology: Lowering Build and Maintenance Costs

2013 ◽  
Author(s):  
Roger Buelow ◽  
Keith Kazenki ◽  
Greg Flies
Keyword(s):  
Energy Efficient ◽  
Light Emitting Diode ◽  
Efficient Technology ◽  
Maintenance Costs ◽  
Light Emitting ◽  
Fluorescent Lamps ◽  
Feasible Option ◽  
Energy Efficient Technology

Due to the recent push for energy efficient technology, LEDs have developed to be able to meet and surpass fluorescent lamps in terms of efficiency and lifetime. Additional focus on LEDs has allowed the initial investment price to decrease allowing LEDs to become a feasible option. Installing LEDs during the construction of ships allows for a greater TOC savings from increased energy efficacy, lower maintenance costs and a simpler electrical design schematic. There are three options available to incorporate LEDs on a ship: LED lamps, LED fixtures or a combination of the two.

scholarly journals Recycling the GaN Waste from LED Industry by Pressurized Leaching Method

Metals ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 861 ◽  
Author(s):  
Wei-Sheng Chen ◽  
Li-Lin Hsu ◽  
Li-Pang Wang
Keyword(s):  
Energy Gap ◽  
Light Emitting Diode ◽  
Economic Value ◽  
Acid Leaching ◽  
High Hardness ◽  
High Energy ◽  
Light Emitting ◽  
Valuable Metals ◽  
Leaching Solution ◽  
Leaching Efficiency

In recent years, with the increasing research and development of the light-emitting diode (LED) industry, which contains gallium nitride (GaN), it is expected that there will be a large amount of related wastes in the future. Gallium has an extremely high economic value, therefore, it is necessary to establish a recycling system for the GaN waste. However, GaN is a direct-gap semiconductor and with its high energy gap, high hardness, and high melting point, these make it difficult to recycle. Therefore, this study will analyze the physical characteristics of LED wastes containing GaN and carry out various leaching methods to leach the valuable metals from the waste optimally. Different acids are used to find out the best reagent for gallium leaching. Different experimental parameters are discussed, such as the effect of the different acid agents, concentration, pressure, liquid-solid mass ratio, temperature and time, which influence the leaching efficiency of gallium. Finally, acid leaching under high pressure is preferred to leach the GaN waste, and hydrochloric acid is used as the leaching solution because of its better leaching efficiency of gallium. Optimally, the leaching efficiency of gallium can reach 98%.

scholarly journals Cell Phone Acne: New Acne Clinical Features in the Coronavirus Disease-19 Era

2021 ◽  
Vol 9 (F) ◽  
pp. 481-485
Author(s):  
Kristin Stephanie Sembiring ◽  
Nelva Karmila Jusuf
Keyword(s):  
Cell Phone ◽  
Heat Dissipation ◽  
Prolonged Exposure ◽  
Light Emitting Diode ◽  
Electronic Devices ◽  
High Energy ◽  
Light Spectrum ◽  
Oil Accumulation ◽  
Light Emitting ◽  
Technological Developments

Technological developments in telecommunications, especially cell phone, enable us to keep communicate without meeting each other. Especially during the latest coronavirus outbreak, when people need to keep up social distance. Meanwhile, electronic devices such as smartphone, tablets, laptops, and light-emitting diode screens are the sources of visible lights that can emit high levels of short-wavelength visible light (blue region in the light spectrum). Prolonged exposure to high-energy blue light, heat dissipation from cell phone, friction, trapped sweat and oil, accumulation of dust, and increased bacterial growth can cause cell phone acne. Management of cell phone acne from prevention to combination therapy based on the results of the evaluation of the severity of acne is needed.

scholarly journals Improved Exposure To Blue Light For Bacterial Death Of Staph

2019 ◽  
Vol 21 (1) ◽  
pp. 13
Author(s):  
Endah Robbiyati
Keyword(s):  
Staphylococcus Aureus ◽  
Light Source ◽  
Blue Light ◽  
Staphylococcus Epidermidis ◽  
Energy Analysis ◽  
Light Emitting Diode ◽  
High Energy ◽  
Light Emitting ◽  
Blue Led ◽  
Correct Energy

ABSTRACTIn this study, bacteria Gram-positive Staphylococcus aureus is exposed to a blue LED light source (light-emitting diode) to determine the appropriate energy to kill the exposure-caused bacteria. The longest exposure times are 1200, 1800, 2400, 3000 seconds, and power 28.098, 56.561, 74.882, and 96.369 MW. The number of bacterial colonies incubated by TPC (total plate number) at 37 degrees 24-48 hours while the plant is alive. Determine the correct energy caused by exposure to the blue LED lamp, therefore, perform mold analysis, non-compliance, and quantitative energy analysis. These results show that the death of streptococcus skin is generally affected by high energy. From this study, we found that 74,882 MW of energy and 179,716.8 MJ of bacteria per 2,400 seconds were the best energy week.Keywords: Staphylococcus epidermidis, a blue LED, exposure time, the power of                   exposure, CFU

scholarly journals Comparing Flowering Responses of Long-day Plants under Incandescent and Two Commercial Light-emitting Diode Lamps

2014 ◽  
Vol 24 (4) ◽  
pp. 490-495 ◽  
Author(s):  
Fumiko Kohyama ◽  
Catherine Whitman ◽  
Erik S. Runkle
Keyword(s):  
Plant Height ◽  
Energy Efficient ◽  
Light Emitting Diode ◽  
Node Number ◽  
Light Emitting ◽  
Daily Light Integral ◽  
Low Intensity ◽  
Long Day ◽  
Long Day Plants ◽  
Light Integral

When the natural daylength is short, commercial growers of ornamental long-day plants (LDP) often provide low-intensity lighting to more rapidly and uniformly induce flowering. Incandescent (INC) lamps have been traditionally used for photoperiodic lighting because their spectrum, rich in red [R (600 to 700 nm)] and far-red [FR (700 to 800 nm)] light, is effective and they are inexpensive to purchase and install. Light-emitting diodes (LEDs) are much more energy efficient, can emit wavelengths of light that specifically regulate flowering, and last at least 20 times longer. We investigated the efficacy of two new commercial LED products developed for flowering applications on the LDP ageratum (Ageratum houstonianum), calibrachoa (Calibrachoa ×hybrida), two cultivars of dianthus (Dianthus chinensis), and two cultivars of petunia (Petunia ×hybrida). Plants were grown under a 9-hour short day without or with a 4-hour night interruption (NI) delivered by one of three lamp types: INC lamps (R:FR = 0.59), LED lamps with R and white (W) diodes [R + W (R:FR = 53.35)], and LED lamps with R, W, and FR diodes [R + W + FR (R:FR = 0.67)]. The experiment was performed twice, both at a constant 20 °C, but the photosynthetic daily light integral (DLI) during the second replicate (Rep. II) was twice that in the first (Rep. I). In all crops and in both experimental replicates, time to flower, flower or inflorescence and node number, and plant height were similar under the R + W + FR LEDs and the INC lamps. However, in Rep. I, both petunia cultivars developed more nodes and flowering was delayed under the R + W LEDs compared with the INC or R + W + FR LEDs. In Rep. II, petunia flowering time and node number were similar under the three NI treatments. Plant height of both dianthus cultivars was generally shorter under the NI treatment without FR light (R + W LEDs). These results indicate that when the DLI is low (e.g., ≤6 mol·m−2·d−1), FR light is required in NI lighting for the most rapid flowering of some but not all LDP; under a higher DLI, the flowering response to FR light in NI lighting is apparently diminished.

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