Performance Optimization of Blue-light Blocking Lens Through Analysis of Blue Light Emitted from LED Light Sources

2016 ◽  
Vol 21 (4) ◽  
pp. 393-400 ◽  
Author(s):  
Younghyun Son ◽  
Seok-Jun Yang ◽  
Chang Jin Kim ◽  
Gyeong Sun Lee ◽  
Su Mi Choi ◽  
...  
Keyword(s):  
Blue Light ◽  
Performance Optimization ◽  
Light Sources ◽  
Led Light

Spectral Design and Optimization of White LED Light Sources with Low Blue Light Hazard

2019 ◽  
Vol 56 (18) ◽  
pp. 182302
Author(s):  
周孟欣 Mengxin Zhou ◽  
朱大庆 Daqing Zhu ◽  
廖欣怡 Xinyi Liao
Keyword(s):  
Blue Light ◽  
Light Sources ◽  
White Led ◽  
Led Light ◽  
Design And Optimization ◽  
Spectral Design

Highly efficient and dual broad emitting light convertor: an option for next-generation plant growth LEDs

2019 ◽  
Vol 7 (12) ◽  
pp. 3617-3622 ◽  
Author(s):  
Mingcai Li ◽  
Xuejie Zhang ◽  
Haoran Zhang ◽  
Weibin Chen ◽  
Li Ma ◽  
...  
Keyword(s):  
Gallium Nitride ◽  
Plant Growth ◽  
Blue Light ◽  
Red Light ◽  
Light Sources ◽  
Full Width ◽  
Half Maximum ◽  
Next Generation ◽  
Led Light ◽  
Generation Plant

At present, blue-red composite LED light sources used for plant lighting are mainly composed of blue light and red light; the blue light is provided by gallium nitride LED chips, but the full-width at half-maximum (FWHW) is only approximately 25 nm, while the blue light required by plants for photosynthesis is wider.

scholarly journals Assessment of blue light retinal hazard of lamps and lights used in automotive

2018 ◽  
Vol 19 (6) ◽  
pp. 548-551
Author(s):  
Marcin Legierski ◽  
Piotr Michałek
Keyword(s):  
Blue Light ◽  
Self Assembly ◽  
Luminous Intensity ◽  
Light Sources ◽  
Colour Temperature ◽  
Led Light ◽  
Chromaticity Coordinates ◽  
Daytime Running Lights

The article contains results of the research on the assessment of the blue light retinal hazard by lighting devices used in the automotive with LED light sources. The study was subject to daytime running lights and work lamps available on the market for self-assembly in vehicles. The study method was presented using a matrix luminance meter and spectroradiometer. The necessary photometric and radiometric tests were carried out. Assessment of blue light hazard according to the PN-EN 62471: 2010 was made. Obtained results were referred to maximum luminous intensity, chromaticity coordinates and correlated colour temperature of tested devices.

Design of Solar-Powered LED Road Lighting System

2019 ◽  
pp. 75-85
Author(s):  
Canan Perdahci ◽  
Hamdi Ozkan
Keyword(s):  
High Pressure ◽  
Renewable Energy Sources ◽  
Junction Temperature ◽  
Mercury Vapour ◽  
Light Sources ◽  
Street Lighting ◽  
Led Light ◽  
Road Lighting ◽  
Lighting Systems ◽  
High Pressure Sodium Lamp

Turkey is rich in terms of renewable energy sources and, therefore, is now encouraging the use of sustainable clean lighting systems in road applications. High pressure sodium lamp is the most widely used type in main roads, but other types of lamps such as mercury vapour lamps or metal halide lamps can be utilized for street lighting. Since it enables energy and money saving, LED light technology has replaced high pressure sodium lamps nowadays. Once solar power system (PV) is integrated with LED lamp for street lighting, the amount of saving and local impact might be enriched. LEDs used as light sources in road lighting luminaires with rising lumen values, decreasing junction temperature, higher colour rendering efficiency, longer lifetime have become more efficient than many light sources with the latest developments. Since the structure of the luminaires in which the LED light sources are used differs from that of the conventional light sources, the optical, thermal and electrical design of the LED luminaires must be considered differently. Thus, this study concentrates upon design considerations and the operating principle of solarpowered LED road lighting luminaire in details. Also, a simple solar panel system was designed and the economical values obtained at the end of 20 years were compared when using the ongrid system and the off-grid system.

scholarly journals Analysis on High-Power Seaport LED Luminaire with Uniform Light Distribution Based on Optimized Lens and Heatsink

2021 ◽  
Vol 11 (9) ◽  
pp. 4035
Author(s):  
Jinsheon Kim ◽  
Jeungmo Kang ◽  
Woojin Jang
Keyword(s):  
Light Source ◽  
High Power ◽  
Heat Dissipation ◽  
Light Emitting Diode ◽  
Light Distribution ◽  
Light Sources ◽  
Led Light ◽  
High Power Led ◽  
Distribution Requirement ◽  
Lighting Application

In the case of light-emitting diode (LED) seaport luminaires, they should be designed in consideration of glare, average illuminance, and overall uniformity. Although it is possible to implement light distribution through auxiliary devices such as reflectors, it means increasing the weight and size of the luminaire, which reduces the feasibility. Considering the special environment of seaport luminaires, which are installed at a height of 30 m or more, it is necessary to reduce the weight of the device, facilitate replacement, and secure a light source with a long life. In this paper, an optimized lens design was investigated to provide uniform light distribution to meet the requirement in the seaport lighting application. Four types of lens were designed and fabricated to verify the uniform light distribution requirement for the seaport lighting application. Using numerical analysis, we optimized the lens that provides the required minimum overall uniformity for the seaport lighting application. A theoretical analysis for the heatsink structure and shape were conducted to reduce the heat from the high-power LED light sources up to 250 W. As a result of these analyses on the heat dissipation characteristics of the high-power LED light source used in the LED seaport luminaire, the heatsink with hexagonal-shape fins shows the best heat dissipation effect. Finally, a prototype LED seaport luminaire with an optimized lens and heat sink was fabricated and tested in a real seaport environment. The light distribution characteristics of this prototype LED seaport luminaire were compared with a commercial high-pressure sodium luminaire and metal halide luminaire.

scholarly journals Single Wavelengths of LED Light Supplement Promote the Biosynthesis of Major Cyclic Monoterpenes in Japanese Mint

Plants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1420
Author(s):  
Takahiro Ueda ◽  
Miki Murata ◽  
Ken Yokawa
Keyword(s):  
Blue Light ◽  
Solid Phase ◽  
Glandular Trichomes ◽  
Red Light ◽  
Glandular Trichome ◽  
Pulse Amplitude ◽  
Light Treatment ◽  
Led Light ◽  
Trichome Formation ◽  
Japanese Mint

Environmental light conditions influence the biosynthesis of monoterpenes in the mint plant. Cyclic terpenes, such as menthol, menthone, pulegone, and menthofuran, are major odor components synthesized in mint leaves. However, it is unclear how light for cultivation affects the contents of these compounds. Artificial lighting using light-emitting diodes (LEDs) for plant cultivation has the advantage of preferential wavelength control. Here, we monitored monoterpene contents in hydroponically cultivated Japanese mint leaves under blue, red, or far-red wavelengths of LED light supplements. Volatile cyclic monoterpenes, pulegone, menthone, menthol, and menthofuran were quantified using the head-space solid phase microextraction method. As a result, all light wavelengths promoted the biosynthesis of the compounds. Remarkably, two weeks of blue-light supplement increased all compounds: pulegone (362% increase compared to the control), menthofuran (285%), menthone (223%), and menthol (389%). Red light slightly promoted pulegone (256%), menthofuran (178%), and menthol (197%). Interestingly, the accumulation of menthone (229%) or menthofuran (339%) was observed with far-red light treatment. The quantification of glandular trichomes density revealed that no increase under light supplement was confirmed. Blue light treatment even suppressed the glandular trichome formation. No promotion of photosynthesis was observed by pulse-amplitude-modulation (PAM) fluorometry. The present result indicates that light supplements directly promoted the biosynthetic pathways of cyclic monoterpenes.

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