The mesopic effect of different correlated color temperature LED light sources on road lighting

2010 ◽  
Author(s):  
Xuan Li ◽  
Shangzhong Jin ◽  
Yanhua Wang ◽  
Songyuan Cen ◽  
Pei Liang ◽  
...  
Keyword(s):  
Color Temperature ◽  
Light Sources ◽  
Led Light ◽  
Road Lighting

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 An Efficient Method for LED Light Sources Characterization

Electronics ◽  
2019 ◽  
Vol 8 (10) ◽  
pp. 1089 ◽  
Author(s):  
Sara Raggiunto ◽  
Alberto Belli ◽  
Lorenzo Palma ◽  
Piergiovanni Ceregioli ◽  
Massimo Gattari ◽  
...  
Keyword(s):  
Efficient Method ◽  
Least Squares Method ◽  
Color Temperature ◽  
Experimental Setup ◽  
Light Sources ◽  
Careful Study ◽  
Source Characterization ◽  
Led Light ◽  
Lighting Systems ◽  
Led Drivers

Digital LED drivers capable of blending the spectrum of two LED fixtures with different Correlated Color Temperatures through the LEDs’ power supply control are widespread. However, the digital control of lighting systems is possible only after a careful study of the LED’s response, in terms of illuminance and Correlated Color Temperature. The proposed work takes advantage of the Tunable White technology for the realization of an efficient method for LED light source characterization. In order to evaluate how the light changes as a function of the electric power supplied by the LED drivers, an experimental setup to characterize LED light sources has been designed. Starting from the data acquired from the experimental setup, a model for dimming the LED driver and obtaining the desired values of quality of light has been developed. The proposed model is based on the least squares method and its accuracy is evaluated by comparing the obtained values of illuminance and Correlated Color Temperature with those measured by an illuminance spectrophotometer. Results achieved an error of 0.3% for Correlated Color Temperature and 1.5% for illuminance using the proposed approximation functions.

Optimization Algorithm of Correlated Color Temperature for LED Light Sources by Dichotomy

2009 ◽  
Vol 29 (10) ◽  
pp. 2791-2794 ◽  
Author(s):  
林岳 Lin Yue ◽  
叶烈武 Ye Liewu ◽  
刘文杰 Liu Wenjie ◽  
吕毅军 Lü Yijun
Keyword(s):  
Optimization Algorithm ◽  
Color Temperature ◽  
Light Sources ◽  
Led Light

Secondary Optical Design of LED Road Lights

2011 ◽  
Vol 301-303 ◽  
pp. 223-228
Author(s):  
Tie Cheng Gao ◽  
Yan Jin Ai ◽  
Xiu Yan Li
Keyword(s):  
Optical Properties ◽  
Full Advantage ◽  
High Power ◽  
Optical Design ◽  
Light Sources ◽  
Led Light ◽  
Road Lighting

Aiming to the application of high-power LEDs in road lights, this article discusses the requirements of optical properties of LED road lights. It carries out the reflector-based secondary optical design of the selected LEDs, which is simulated with ASAP. The results show that this design can take full advantage of the optical properties of LED light sources, greatly improve the efficiency of LED road lights, and improve the uniformity of road lighting, so as to achieve the effects with which those effects produced from the traditional lights cannot be compared.

scholarly journals The Circadian Effect Versus Mesopic Vision Effect in Road Lighting Applications

2020 ◽  
Vol 10 (19) ◽  
pp. 6975
Author(s):  
Min Li ◽  
Peiyu Wu ◽  
Jianhua Ding ◽  
Qi Yao ◽  
Jiaqi Ju
Keyword(s):  
Threshold Value ◽  
Lighting Design ◽  
Color Temperature ◽  
Light Sources ◽  
Good Strategy ◽  
Significant Issue ◽  
Mesopic Vision ◽  
Road Lighting ◽  
Circadian Effect

Several models on the circadian effect have been applied to indoor circadian lighting design, but applications in road lighting have not yet been clarified. Based on existing models and circadian research, we examined equivalent melanopic lux (EML), circadian light (CLA), and circadian stimulus (CS) representing the circadian effect and the S/P ratio representing the mesopic vision effect, among a dataset of light sources at photopic adaptation illuminance values of 1, 3, 10, 30, and 100 lx. The results show that the S/P ratio correlates with EML and CS (or CLA) much stronger than it correlates with color temperature. The EMLs of light sources are below 50 EML in mesopic vision, and the CSs of most light sources are below or around the threshold value of 0.05. We conclude that the circadian effect is not a significant issue in mesopic vision under most conditions and that optimization for mesopic efficiency is still a good strategy. There are quite a few light sources that may achieve both ideal mesopic efficiency and low CS. This work clarifies the circadian effect and mesopic vision effect performance of light sources in mesopic vision and will help guide choosing suitable light sources and optimization strategies for road lighting.

Sign in / Sign up

Export Citation Format

Share Document