{"title":"Comparison of Life Cycle Assessments of LED Light Sources","authors":"Leena Tähkämö, M. Puolakka, L. Halonen, G. Zissis","doi":"10.2150/JLVE.36.44","DOIUrl":"https://doi.org/10.2150/JLVE.36.44","url":null,"abstract":"Several life cycle assessments of light sources have been conducted during last two decades. This article compares their methods and results, and identifies the challenges. Light-emitting diode (LED) is considered as an environmentally friendly solution for lighting. The LEDs have the potential to be the most environmentally friendly light sources not least because of their increasing luminous efficacy and long lifetime. However, there are neither detailed data nor a profound life cycle assessment of a range of LED lighting products to undisputedly prove their environmental performance. Currently, the total life cycle environmental impacts of LED light sources are not known due to uncertainties and lack of peer-reviewed","PeriodicalId":311488,"journal":{"name":"Journal of Light & Visual Environment","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129006394","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Light-emission Properties of Europium-doped Tantalum-oxide Thin Films Deposited by Radio-frequency Magnetron Sputtering","authors":"K. Miura, Y. Arai, T. Osawa, O. Hanaizumi","doi":"10.2150/JLVE.36.64","DOIUrl":"https://doi.org/10.2150/JLVE.36.64","url":null,"abstract":"Light-emitting europium-doped tantalum-oxide thin films were prepared by radio-frequency magnetron sputtering. Red photoluminescence was obtained from the films after annealing by ultraviolet-laser excitation. Four peaks having wavelengths of around 600, 620, 650, and 700 nm were observed from films annealed at 600 to 900°C. The strongest intensity of the most remarkable 620-nm peak was obtained from the film annealed at 700°C for 20 min.","PeriodicalId":311488,"journal":{"name":"Journal of Light & Visual Environment","volume":"120 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133181273","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Energy Efficient Lighting System Design for Hospitals Diagnostic and Treatment Room—A Case Study","authors":"S. Alzubaidi, P. K. Soori","doi":"10.2150/JLVE.36.23","DOIUrl":"https://doi.org/10.2150/JLVE.36.23","url":null,"abstract":"Lighting plays an important role in the Hospital Diagnostic and Treatment Room. It shall be environmentally and functionally suitable for three groups of people: patients, hospital professionals and visitors. On the other hand lighting is considered a major consumer of electrical energy and therefore, hospital lighting design should consider the visual performance, visual comfort and energy efficiency. This article discusses the performance of different types of lighting installations used for hospital lighting system design applications: first the visual comfort and second to save energy consumptions in such applications. DIALux 4.8 simulation software is used to study and evaluate the efficient lighting scheme for the hospitals through the use of different types of lamps. Also, visual environment lighting system design procedure is explained. Economics of different lighting scenarios are highlighted.","PeriodicalId":311488,"journal":{"name":"Journal of Light & Visual Environment","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132039144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Characteristics of the Brightness Perception under the Dark Adaptation","authors":"K. Sendai, M. Takamatsu, Y. Nakashima","doi":"10.2150/JLVE.36.10","DOIUrl":"https://doi.org/10.2150/JLVE.36.10","url":null,"abstract":"Outdoor signboards on the street provide not only advertising but also effective scenery of the town, and they are useful for the activation of the town. Sometimes they have different faces according to the effect of the lighting systems in daytime and night time. In this experiment, we use lighted signboards to examine how human eyes see “object colors” under the dark conditions. Advertising signboards that we recognize as “object colors” begin to change into “light source colors,” when it darkens gradually in the night time. When this change occurs, the horizontal illuminance decreases from 1000 to 100 lx. In addition, “brightness feeling” and the ratio of “light source colors” rise rapidly when the luminance difference between the sky and signboard falls below 200 cd/m2. We think our results will be useful to develop and control signboard lighting in the field of energy saving technology.","PeriodicalId":311488,"journal":{"name":"Journal of Light & Visual Environment","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122712861","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Erratum: Mapping the World of Light Sources Research [J. Light Vis. Environ. 35(3): 283-284 (2011)]","authors":"S. Kitsinelis","doi":"10.2150/JLVE.36.35","DOIUrl":"https://doi.org/10.2150/JLVE.36.35","url":null,"abstract":"","PeriodicalId":311488,"journal":{"name":"Journal of Light & Visual Environment","volume":"304 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125828664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Challenges in This Year, Beyond the Earthquake Disaster","authors":"Tomohiko Ohno","doi":"10.2150/JLVE.36.5","DOIUrl":"https://doi.org/10.2150/JLVE.36.5","url":null,"abstract":"","PeriodicalId":311488,"journal":{"name":"Journal of Light & Visual Environment","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130348751","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Daylighting and Its Impact on Depth Perception in a Daylit Space","authors":"Nan-Ching Tai","doi":"10.2150/JLVE.36.16","DOIUrl":"https://doi.org/10.2150/JLVE.36.16","url":null,"abstract":"Visual perception within a daylit environment changes according to spatiality, sky conditions, time, and the point of observation. This paper focuses on the complex interrelationships among the architectural configuration of skylights, luminance distribution patterns resulting from changing sky conditions, and the perception of spatial depth. This study employed lighting simulation techniques that incorporate physically based rendering and perceptually based tone mapping to generate a pictorial environment. Daylighting conditions were parametrically changed and psychophysical experiments were conducted to measure the perception of distance to visual targets within architectural scenes illuminated by various daylighting conditions. Results reveal that perceived distance to visual targets increases with a decrease in the luminance contrast between the target and background. This paper concludes that variations in luminance within a space influence perceptions of spatial depth, providing the possibility of enriching the experience of architectural scenes through the incorporation of daylighting in design strategies.","PeriodicalId":311488,"journal":{"name":"Journal of Light & Visual Environment","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116923165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Kitaura, Ai Harima, R. Xie, T. Takeda, N. Hirosaki, A. Ohnishi, M. Sasaki
{"title":"Electron Spin Resonance Study on Local Structure of Manganese Ions Doped in Gamma-Aluminum Oxynitride Phosphors","authors":"M. Kitaura, Ai Harima, R. Xie, T. Takeda, N. Hirosaki, A. Ohnishi, M. Sasaki","doi":"10.2150/JLVE.36.6","DOIUrl":"https://doi.org/10.2150/JLVE.36.6","url":null,"abstract":"We have studied the local structure of manganese ion doped in gamma aluminum oxynitride phosphors ( γ -AlON: Mn) using electron spin resonance (ESR) experiment. Six sharp peaks appear in ESR spectra of γ -AlON: Mn, together with five weak doublets. These structures are caused by the hyperfine interaction of 3 d electrons with the 55 Mn nucleus of spin I = 5/2. The six peaks are attributed to the allowed transitions (Δ M I = 0) between hyperfine splitting states of M s =(cid:156) 1/2. The five doublets are interpreted as the forbidden transitions (Δ M I =(cid:156) 1) between the hyperfine splitting states. The spectral feature of γ -AlON: Mn resembles with the ESR spectrum of Mn 2 + doped MgAl 2 O 4 spinel, in which Mn 2 + ions are substituted for tetrahedral Mg 2 + sites. Since γ -AlON is also of the spinel structure, it is suggested that Mn 2 + ions occupy tetrahedral Al 3 + sites. We further chased the effect of Mg 2 + co-doping on ESR spectra of Mn 2 + ions in γ -AlON, in order to elucidate the luminescence enhancement in γ -AlON: Mn, Mg. It turned out that the Mg 2 + co-doping increases Mn 2 + ions at tetrahedral Al 3 + sites.","PeriodicalId":311488,"journal":{"name":"Journal of Light & Visual Environment","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132796367","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"BR30 Reflector Compact Fluorescent Lamp with Improved Run-up Performance","authors":"Xiangfen Feng","doi":"10.2150/JLVE.36.32","DOIUrl":"https://doi.org/10.2150/JLVE.36.32","url":null,"abstract":"The run up characteristics of BR30 re fl ector compact fl uorescent lamps are investigated to optimize lamp design for performance improvements. The design is optimized based on the current re fl ector amalgam lamp, characterized in that the solid mercury is added into the discharge tube and the paraf fi n wax is put at the bottom of the re fl ector to connect the discharge tube and the re fl ector bottom together. The experimental results show that the run-up time can be shortened by about 20 s, the light ef fi cacy can be increased by about 5 lm/W, and the bottom temperature of the discharge tube can be reduced by about 25 ° C by the optimized re fl ector lamp design.","PeriodicalId":311488,"journal":{"name":"Journal of Light & Visual Environment","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123820530","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Toward a Definition of Circadian Light","authors":"M. Rea","doi":"10.2150/JLVE.35.250","DOIUrl":"https://doi.org/10.2150/JLVE.35.250","url":null,"abstract":"Light is formally defined in terms of the photopic luminous efficiency function [V(λ)], but the spectral sensitivity of the human circadian system is poorly characterized by this spectral weighting function. A new definition of circadian light should be considered because of the impact that fabricated and natural light sources may have on human health and well-being. Establishment of a formal definition of circadian light could lay the foundation for a new generation of lighting professionals and better lighting standards.","PeriodicalId":311488,"journal":{"name":"Journal of Light & Visual Environment","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114349588","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}