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Author Ho, C.Y.; Lin, H.T.; Huang, K.Y. url  doi
openurl 
  Title A Study on Energy Saving and Light Pollution of LED Advertising Signs Type Journal Article
  Year 2011 Publication Applied Mechanics and Materials Abbreviated Journal Amm  
  Volume 121-126 Issue Pages (down) 2979-2984  
  Keywords Advertising Sign; LED; Light Trespass; Luminance Limit; Saving Energy; Vertical Illuminance; *Lighting  
  Abstract Lighting advertising signs not only play an important role in outdoor lighting environment in Taiwan, but also become the main factor of energy consumption in urban areas at night. Light-emitting diode (LED) has been gradually used in advertising signs due to its advantages. However, in order to be conspicuous and legible in the daytime, signs that are excessively bright may result in considerable light pollution and energy waste at nighttime. Therefore, this research aims to measure the luminance of LED signs and traditional internally lighted signs, and analyze the light trespass from each signage. Based on the research results, the energy consumption from a LED full color screen is 12 times more than a traditional internally lighted sign per day. Statistically, all kinds of LED signs are much higher than traditional internally lighted signs in the percentage of excessive brightness and average luminance value. As for the light trespass, since the vertical illuminance on facade facing the signs increases with the increase of the sign area or the decrease of the distance between the sign and the facade, the vertical illuminance on facade facing the signs would exceed the limit of CIE even if the luminance of the signs achieves the standard of CIE in terms of the general conditions in Taiwan. This happens to LED full color screens in particular and thus results in considerable obtrusive light. To sum up, in order to reduce unnecessary energy consumption and improve the nighttime lighting quality for outdoor environment, this research recommends the luminance limitation for light dimming of LED advertising signs should refer to the zoning, time period, and sign area.  
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  ISSN 1662-7482 ISBN Medium  
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  Notes Approved no  
  Call Number IDA @ john @ Serial 126  
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Author Yoon, H.C.; Oh, J.H.; Lee, S.; Park, J.B.; Do, Y.R. url  doi
openurl 
  Title Circadian-tunable Perovskite Quantum Dot-based Down-Converted Multi-Package White LED with a Color Fidelity Index over 90 Type Journal Article
  Year 2017 Publication Scientific Reports Abbreviated Journal Sci Rep  
  Volume 7 Issue 1 Pages (down) 2808  
  Keywords Lighting  
  Abstract New metrics of the color and circadian performances of down-converted white light-emitting diodes (DC-WLEDs) are rapidly becoming popular in smart lighting systems. This is due to the increased desire for accurate analytical methods to measure the effects of newly developed quantum dot (QD)-based lighting on the vision, color, and circadian sensors of retina cells in the human eye. In this regard, a two-measure system known as technical memorandum TM-30-2015 (Illuminating Engineering Society of North America), encompassing the color fidelity index (CFI, R f ) and the color gamut index (CGI, R g ), has been developed as a new metrics of color to replace the currently utilized color rendering index (CRI, R a ). In addition, the tunability of the circadian efficacy of radiation (CER) is now more important due to its effect on the control of melatonin suppression/secretion, resetting of the central/local clocks of individuals given their daily cycles, and benefits to human health. In this paper, we developed and analyzed six-colored perovskite (Pe; cyan, green, yellowish green, amber, orange, and red colors) QDs-based multi-package WLED, and optimized the SPDs of tunable PeQD-based multi-package WLEDs in terms of promising human-centric lighting device, given its optimized visual energy, color qualities and health-promoting effects.  
  Address Department of Chemistry, Kookmin University, Seoul, 136-702, Republic of Korea. yrdo@kookmin.ac.kr  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 2045-2322 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:28584229; PMCID:PMC5459832 Approved no  
  Call Number LoNNe @ kyba @ Serial 1667  
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Author Kayumov, L.; Casper, R.F.; Hawa, R.J.; Perelman, B.; Chung, S.A.; Sokalsky, S.; Shapiro, C.M. url  doi
openurl 
  Title Blocking low-wavelength light prevents nocturnal melatonin suppression with no adverse effect on performance during simulated shift work Type Journal Article
  Year 2005 Publication The Journal of Clinical Endocrinology and Metabolism Abbreviated Journal J Clin Endocrinol Metab  
  Volume 90 Issue 5 Pages (down) 2755-2761  
  Keywords Lighting; Adult; *Circadian Rhythm; Female; Humans; *Light; Male; Melatonin/*secretion; *Work Schedule Tolerance  
  Abstract Decreases in melatonin production in human and animals are known to be caused by environmental lighting, especially short-wavelength lighting (between 470 and 525 nm). We investigated the novel hypothesis that the use of goggles with selective exclusion of all wavelengths less than 530 nm could prevent the suppression of melatonin in bright-light conditions during a simulated shift-work experiment. Salivary melatonin levels were measured under dim (<5 lux), bright (800 lux), and filtered (800 lux) light at hourly intervals between 2000 and 0800 h in 11 healthy young males and eight females (mean age, 24.7 +/- 4.6 yr). The measurements were performed during three nonconsecutive nights over a 2-wk period. Subjective sleepiness was measured by self-report scales, whereas objective performance was assessed with the Continuous Performance Test. All subjects demonstrated preserved melatonin levels in filtered light similar to their dim-light secretion profile. Unfiltered bright light drastically suppressed melatonin production. Normalization of endogenous melatonin production while wearing goggles did not impair measures of performance, subjective sleepiness, or alertness.  
  Address Sleep Research Laboratory, Department of Psychiatry, University Health Network, ECW 3D-035, 399 Bathurst Street, Toronto, Ontario, Canada M5T 2S8. lkayumov@uhnres.utoronto.ca  
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  ISSN 0021-972X ISBN Medium  
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  Notes PMID:15713707 Approved no  
  Call Number LoNNe @ kagoburian @ Serial 640  
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Author Falchi, F.; Cinzano, P.; Elvidge, C.D.; Keith, D.M.; Haim, A. url  doi
openurl 
  Title Limiting the impact of light pollution on human health, environment and stellar visibility Type Journal Article
  Year 2011 Publication Journal of Environmental Management Abbreviated Journal J Environ Manage  
  Volume 92 Issue 10 Pages (down) 2714-2722  
  Keywords Animals; Animals, Wild; Conservation of Natural Resources; Environment; *Environmental Pollution; Eye; *Health; Humans; Lighting/*adverse effects/standards; Melatonin/*antagonists & inhibitors; Sodium; Vision, Ocular/*physiology; Visual Perception  
  Abstract Light pollution is one of the most rapidly increasing types of environmental degradation. Its levels have been growing exponentially over the natural nocturnal lighting levels provided by starlight and moonlight. To limit this pollution several effective practices have been defined: the use of shielding on lighting fixture to prevent direct upward light, particularly at low angles above the horizon; no over lighting, i.e. avoid using higher lighting levels than strictly needed for the task, constraining illumination to the area where it is needed and the time it will be used. Nevertheless, even after the best control of the light distribution is reached and when the proper quantity of light is used, some upward light emission remains, due to reflections from the lit surfaces and atmospheric scatter. The environmental impact of this “residual light pollution”, cannot be neglected and should be limited too. Here we propose a new way to limit the effects of this residual light pollution on wildlife, human health and stellar visibility. We performed analysis of the spectra of common types of lamps for external use, including the new LEDs. We evaluated their emissions relative to the spectral response functions of human eye photoreceptors, in the photopic, scotopic and the 'meltopic' melatonin suppressing bands. We found that the amount of pollution is strongly dependent on the spectral characteristics of the lamps, with the more environmentally friendly lamps being low pressure sodium, followed by high pressure sodium. Most polluting are the lamps with a strong blue emission, like Metal Halide and white LEDs. Migration from the now widely used sodium lamps to white lamps (MH and LEDs) would produce an increase of pollution in the scotopic and melatonin suppression bands of more than five times the present levels, supposing the same photopic installed flux. This increase will exacerbate known and possible unknown effects of light pollution on human health, environment and on visual perception of the Universe by humans. We present quantitative criteria to evaluate the lamps based on their spectral emissions and we suggest regulatory limits for future lighting.  
  Address Istituto di Scienza e Tecnologia dell'Inquinamento Luminoso, Via Roma 13, I-36106 Thiene, Italy. falchi@lightpollution.it  
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  Series Volume Series Issue Edition  
  ISSN 0301-4797 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:21745709 Approved no  
  Call Number IDA @ john @ Serial 131  
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Author Gaston, K.J.; Holt, L.A. url  doi
openurl 
  Title Nature, extent and ecological implications of night‐time light from road vehicles Type Journal Article
  Year 2018 Publication Journal of Applied Ecology Abbreviated Journal  
  Volume 55 Issue 5 Pages (down) 2296-2307  
  Keywords Animals; Ecology; Lighting; Review  
  Abstract The erosion of night‐time by the introduction of artificial lighting constitutes a profound pressure on the natural environment. It has altered what had for millennia been reliable signals from natural light cycles used for regulating a host of biological processes, with impacts ranging from changes in gene expression to ecosystem processes.

Studies of these impacts have focused almost exclusively on those resulting from stationary sources of light emissions, and particularly streetlights. However, mobile sources, especially road vehicle headlights, contribute substantial additional emissions.

The ecological impacts of light emissions from vehicle headlights are likely to be especially high because these are (1) focused so as to light roadsides at higher intensities than commonly experienced from other sources, and well above activation thresholds for many biological processes; (2) projected largely in a horizontal plane and thus can carry over long distances; (3) introduced into much larger areas of the landscape than experience street lighting; (4) typically broad “white” spectrum, which substantially overlaps the action spectra of many biological processes and (5) often experienced at roadsides as series of pulses of light (produced by passage of vehicles), a dynamic known to have major biological impacts.

The ecological impacts of road vehicle headlights will markedly increase with projected global growth in numbers of vehicles and the road network, increasing the local severity of emissions (because vehicle numbers are increasing faster than growth in the road network) and introducing emissions into areas from which they were previously absent. The effects will be further exacerbated by technological developments that are increasing the intensity of headlight emissions and the amounts of blue light in emission spectra.

Synthesis and applications. Emissions from vehicle headlights need to be considered as a major, and growing, source of ecological impacts of artificial night‐time lighting. It will be a significant challenge to minimise these impacts whilst balancing drivers' needs at night and avoiding risk and discomfort for other road users. Nonetheless, there is potential to identify solutions to these conflicts, both through the design of headlights and that of roads.
 
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  Call Number GFZ @ kyba @ Serial 1841  
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