T. Kashiwao, T. Takiguchi, T. Miyamura, K. Ikeda, T. Shimomura
{"title":"Development of a 2D Optical Simulator for SMD LED Packaging","authors":"T. Kashiwao, T. Takiguchi, T. Miyamura, K. Ikeda, T. Shimomura","doi":"10.2150/JLVE.IEIJ140000539","DOIUrl":"https://doi.org/10.2150/JLVE.IEIJ140000539","url":null,"abstract":"This paper reports on the development of a two-dimensional (2D) optical simulator for surface mount device (SMD) light emitting diode (LED) packaging (PKG). In the early phase of the development of an LED, an optical simulator is important for designing the LED PKG; thus, we have developed a 2D optical simulator specialized for this purpose. This simulator provides an easy and simple interface for setting simulation parameters. In addition, simulations can be executed quickly because the method used by the simulator produces a result by multiplying the vertical and horizontal results from a 2D simulation. In this paper, we present simulation results showing the relative intensity distribution of the light emitting surface of a side view (SV) LED.","PeriodicalId":311488,"journal":{"name":"Journal of Light & Visual Environment","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123676094","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}
Sakura Kano, D. Ito, Etsuko Mochizuki, T. Iwata, Yoshiki Nakamura
{"title":"Pilot Study of Reconsideration of the Lighting Environment in Train Stations under the Restriction of Power Use due to the Aftermath of the Great East Japan Earthquake","authors":"Sakura Kano, D. Ito, Etsuko Mochizuki, T. Iwata, Yoshiki Nakamura","doi":"10.2150/JLVE.IEIJ140000495","DOIUrl":"https://doi.org/10.2150/JLVE.IEIJ140000495","url":null,"abstract":"Field measurements were conducted to identify how the actual lighting environment has changed in train stations due to the aftermath of the Great East Japan Earthquake. Horizontal illuminance on the floor on the way from the platform to the exit of the station and the number of the lighted luminaires in each area of each station were measured. The measurements were conducted twice, in the summer and in the autumn 2011, to identify the continuity of electricity saving measures and the transition of the lighting environment. From the results of the measurements in the summer, it was identified that nearly 80% of the luminaires was lighted off in maximum. The results of our survey showed the possibility to lower the floor illuminance level for some areas where the passengers felt no inconvenience in walking, such as the ticket gates area and concourse.","PeriodicalId":311488,"journal":{"name":"Journal of Light & Visual Environment","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124595241","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}
Kimura Masayoshi, Satoshi Hirakawa, Uchino Hirohito, H. Motomura, M. Jinno
{"title":"Energy Savings in Tunnel Lighting by Improving the Road Surface Luminance Uniformity—A New Approach to Tunnel Lighting—","authors":"Kimura Masayoshi, Satoshi Hirakawa, Uchino Hirohito, H. Motomura, M. Jinno","doi":"10.2150/JLVE.IEIJ120000487","DOIUrl":"https://doi.org/10.2150/JLVE.IEIJ120000487","url":null,"abstract":"The authors propose a new method for tunnel illumination using LED lights. The luminous characteristics of tunnel lighting employing LED luminaires were measured in the Shiratori tunnel on the Japanese expressway. The results show that this method achieves over 0.9 of luminance uniformity. Moreover, the visual impression evaluation that was conducted using 29 subjects, shows that roads with over 0.9 luminance uniformity and luminance of 2.3 cd/m2, have equivalent or better visibility than roads with low uniformity and luminance of 3.5 cd/m2. This result suggests that the High Luminance Uniformity Method which we propose could save up to 20% of the energy used for illumination and improve safety due to","PeriodicalId":311488,"journal":{"name":"Journal of Light & Visual Environment","volume":"455 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120976297","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":"A Requisite of a Permittivity of the Interfacing Medium for the Electromagnetic Surface Excitation by a Vertical Electric Dipole nearby the Interface","authors":"Y. Ishido","doi":"10.2150/JLVE.IEIJ140000538","DOIUrl":"https://doi.org/10.2150/JLVE.IEIJ140000538","url":null,"abstract":"In planer-type optical devices such as OLED, the loss-propagating surface plasmon polaritons (SPPs) at the interface on a metallic cathode has been regarded as holding the key to the efficiency improvement. It complicates the characteristics of SPPs, however, that the existence of the classical or phenomenological surface electromagnetic (EM) propagation modes at the interface. With the aid of tracing the predecessorsʼ prior achievements, we clarify theoretically the characteristic of surface EM modes over a comprehensive variety of a permittivity of the interfacing medium. As a result, we prove that there is a requisite in order that the surface EM excitations might be quasi independently observed in a vertical dipole radiation nearby the interface, which is non-positive real part of a permittivity of the medium interfacing to the air, such as a real metal, involving the condition for existence of SPPs.","PeriodicalId":311488,"journal":{"name":"Journal of Light & Visual Environment","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129484138","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":"Difference of Predicted Values by Near-infrared Spectrometers Caused by Wavelength Resolution","authors":"T. Okura, S. Piao, S. Kawano","doi":"10.2150/JLVE.IEIJ140000537","DOIUrl":"https://doi.org/10.2150/JLVE.IEIJ140000537","url":null,"abstract":"Near-infrared spectroscopy (NIRS) is an efficient and non-destructive method for quantitatively analyzing ingredients in a material. However, this method requires an expensive and time-consuming process to establish a calibration model. As a consequence, once the calibration model is established, it usually is used for many other spectrometers. Then, more or less a disparity in the predicted ingredient content of the material is observed. This phenomenon is called the instrumental difference and gives a difficulty in the application of NIRS. The reason is that waveform of near-infrared (NIR) spectrum is influenced by the characteristics of the spectrometer. We examined the process of measurement and found the spectral waveform was distorted by the variation of spectral response within wavelength resolution of the spectrometer. Therefore, the large spectral response variation and low wavelength resolution causes the big waveform distortion and then the big difference of predicted value of contents. Using seven linear array spectrometers, we analyzed this distortion and evaluated the difference of the predicted value. The results coincided with the analysis. By understanding the mechanisms of instrumental difference, we can design a spectrometer with minimal instrumental difference. This result could be applied to any other spectroscopy that acquires spectral waveform by dividing the sample waveform by the reference waveform.","PeriodicalId":311488,"journal":{"name":"Journal of Light & Visual Environment","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125767289","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":"A Study on the Effect of Interior Gradation Pattern on Sense of Roominess in Car Room","authors":"T. Koga, Y. Tabuchi, Y. Suda","doi":"10.2150/JLVE.IEIJ130000526","DOIUrl":"https://doi.org/10.2150/JLVE.IEIJ130000526","url":null,"abstract":"Cars are requested to obtain a wide room space and a compact package at the same time. Expression of depth through gradation of brightness is known well in general, and in this study, subjects were experi-mented whether car room could be shown larger when this method using a gradation tunnel pattern, was applied to the interior of a car. Following results were derived from the experiment, by sorting and analyzing subjects ʼ comments and analyzing variances of numerical data, and it was clarified that the method is influential in the sense of depth.","PeriodicalId":311488,"journal":{"name":"Journal of Light & Visual Environment","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130753219","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":"Science and Technology in Lighting and Vision for Transportation","authors":"Y. Suda","doi":"10.2150/JLVE.IEIJ14A00005","DOIUrl":"https://doi.org/10.2150/JLVE.IEIJ14A00005","url":null,"abstract":"","PeriodicalId":311488,"journal":{"name":"Journal of Light & Visual Environment","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129281745","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":"Estimation Method and Simulation of Brightness of Monochromatic LED Point Source Perceived by the Elderly and Protanopes","authors":"Taka-aki Suzuki, Saki Sukoyaka","doi":"10.2150/JLVE.IEIJ130000532","DOIUrl":"https://doi.org/10.2150/JLVE.IEIJ130000532","url":null,"abstract":"This study aimed at estimating the brightness of a monochromatic LED point source as perceived by the elderly and protanopes. In order to estimate the perceived brightness of the monochromatic LED point source for the elderly and protanopes, we defined an index, brightness perception efficiency, which is a ratio of perceived luminosity with spectral luminous efficiency of the elderly or protanopes to the luminosity with standard spectral luminous efficiency. The brightness perception efficiency was calculated using both the LED spectral radiant intensity defined by a peak wavelength and a full width at half maximum (FWHM) of the LED, and the spectral luminous efficiencies of the elderly in their 70s and protanopes. The brightness perception efficiency indicated that monochromatic LED point sources with a broad FWHM effectively attenuate the reduction in perceived brightness of the elderly and protanopes. It is expected that in the case of a peak wavelength of 475 nm the elderly perceive brightness equivalent to 1.6 times luminosity for the LED with a FWHM of 100 nm compared to that with a FWHM of 15 nm, and in the case of a peak wavelength of 635 nm protanopes perceived brightness equivalent to about 3 times luminosity for the LED with a FWHM of 100 nm compared to that with a FWHM of 15 nm. Based on the brightness perception efficiency, we developed an LED illumination simulator that allows the young observers with normal color vision to experience the brightness perceived by the elderly and protanopes.","PeriodicalId":311488,"journal":{"name":"Journal of Light & Visual Environment","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131503776","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":"Symbolized Intersection Sign \"Co Co Mark\"","authors":"T. Yoshii","doi":"10.2150/JLVE.IEIJ130000530","DOIUrl":"https://doi.org/10.2150/JLVE.IEIJ130000530","url":null,"abstract":"This paper introduces a system of symbolized intersection and its effectiveness. In the system, each intersection has been named as one of alphabet, and the guide sign of an alphabet is placed at each intersection. The guide sign can be clearly distinguished by drivers and also it can be understandable from longer distance. Because of these properties, sudden deceleration or dull traveling is expected to be decreased and consequently safety/smoothness of the traffic is expected to be improved. Also, the guide signs are expected to bring more understandable route guidance. The guide signs named “ Co Co Mark ” are proposed and are actually used in Kochi city. The knowledge of the benefit acquired through the experiment on the actual road network is shown below.","PeriodicalId":311488,"journal":{"name":"Journal of Light & Visual Environment","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126103687","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":"High Color Rendering Properties of Full-color LED Light Equipment at AIST","authors":"S. Tamura, T. Hiraga, Hideo Sugimoto","doi":"10.2150/JLVE.IEIJ130000519","DOIUrl":"https://doi.org/10.2150/JLVE.IEIJ130000519","url":null,"abstract":"Color rendering property (Ra) is one of the important indexes to evaluate the performance of illuminant. Controlling the light intensities for the four kinds of color LEDs (red, green, blue and white) on the porta-ble-sized full-color LED panel, and then adding blue LED with different wavelength, the authors gained the high rendering property of Ra = 96. At that time the Ra of the white LED was 87. This result concludes that it is possible to obtain superior color rendering property (Ra) even if the Ra of the white illumination alone is not high.","PeriodicalId":311488,"journal":{"name":"Journal of Light & Visual Environment","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132725100","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}