修车大队一品楼qm论坛51一品茶楼论坛,栖凤楼品茶全国楼凤app软件 ,栖凤阁全国论坛入口,广州百花丛bhc论坛杭州百花坊妃子阁

oe1(光电查) - 科学论文

过滤筛选

出版时间
  • 2018
研究主题
  • sodium lighting system
  • modeling
  • radiation curves
  • LED lighting system
  • software goniophotometer
  • upper half-space
  • light-emitting diode (LED)
  • bulb's replacement
  • lighting parameters at the workplace
  • light sources for household
应用领域
  • Electrical Engineering and Automation
机构单位
  • VSB-TU Ostrava
  • Poznan University of Technology
  • Central Institute for Labour Protection - National Research Institute
188 条数据
?? 中文（中国） ▾

  • Full-visible-spectrum lighting enabled by an excellent cyan-emitting garnet phosphor

    摘要： The development of phosphor materials with outstanding photoluminescence properties is critical for next-generation high-quality solid-state white lighting. As there is a blue-green cavity existed in the emission spectra of the traditional phosphor-converted white-light-emitting diodes (w-LEDs), cyan-emitting phosphor serves an important function in compensating the spectral gap to realize the “full-visible-spectrum lighting”. Herein, we reported the discovery of an efficient cyan-emitting Ce3+-doped Ca2YHf2Al3O12 (CYHAO) garnet phosphor with good thermal stability. The as-prepared CYHAO:Ce3+ phosphor exhibited a broad excitation band in the range of 360 to 460 nm with a maximum at 408 nm, making this phosphor compatible with an efficient 400 nm NUV-emitting LED chip. Under the 408 nm excitation, the optimal sample of CYHAO:0.03Ce3+ exhibited bright broadband cyan emission (λem = 493 nm; bandwidth = 100 nm) together with extra-high internal quantum efficiency (IQE) of 89.5% and external quantum efficiency (EQE) of 69.1%. Notably, the as-prepared CYHAO:0.03Ce3+ phosphor showed good thermal stability (64.2% of emission intensity retained at 423K) and excellent color stability when working in the temperature range of 303-463 K. Importantly, the constructed w-LED device exhibited bright well-distributed warm white light with high color rendering index (CRI; Ra = 93.5 and R12 = 90.4) and low correlated color temperature (3700 K) under 60 mA driven current, indicating that the title cyan phosphor can be utilized as the compensation of the blue-green cavity to apply in full-visible-spectrum lighting. Furthermore, these findings provide new insights into exploring high-performance cyan phosphors for NUV-pumped high-CRI warm w-LEDs.

    关键词： White LEDs,Color rendering index,Cyan emissions,Phosphors,Full-visible-spectrum lighting

    更新于2025-09-23 15:21:01

  • [IEEE 2019 4th International Conference on Information Technology, Information Systems and Electrical Engineering (ICITISEE) - Yogyakarta, Indonesia (2019.11.20-2019.11.21)] 2019 4th International Conference on Information Technology, Information Systems and Electrical Engineering (ICITISEE) - The Mapping of Lighting Intensity from the Light Distribution on LED and CFL Lamps

    摘要： Electricity is an essential need for humans, specifically for the lighting function. Lighting is needed to aid humans visually perceive objects in areas that require lighting, both at night and during the day. At this day, there are two type of lamps that are extensively employed, paticularly the type of Light-Emitting Diode (LED) and Compact Fluorescent Lamp (CFL). The adoption of lights in an area takes a lot of energy, so it is particularly crucial to choose the appropriate type of lamp that is adequate to perform effectively and efficiently. To determine the light distribution of the two types of lights, it is crucial to investigate the distribution of light. The investigation was carried out by the direct measurement technique on 6 and 8 watt LED lamps, as well as on CFL lamps 11 and 14 watt using luxmeter in an area projecting 3x4 meters. The analysis range is varied in several horizontal and vertical points. From the assessment results it was noticed that the LED and CFL lamps the value of the light intensity reduces if the horizontal and vertical distance of the measurement point are far from the lamp. The ends of the light distribution mapping discovered that the light distribution on the LED lights is better indeed and brighter at each point. This is because all the electrons recombine with holes. Whereas in the CFL lamp there has been a filament heating and ionization between the electrons with argon gas and mercury vapor which generates another energy which is relatively large heat energy.

    关键词： CFL,Light Distribution,Lighting Intensity,Mapping,LED

    更新于2025-09-23 15:21:01

  • [IEEE 2018 15th IEEE India Council International Conference (INDICON) - Coimbatore, India (2018.12.16-2018.12.18)] 2018 15th IEEE India Council International Conference (INDICON) - Safety of Light Emitting Diode (LED) Based Domestic Lighting in Rural Context

    摘要： As per 2011 census, 69% of Indians live in the rural settings, who are primarily dependent on subsistence agriculture. Rural house-holds use power lighting, operating household appliances and agricultural works. Home-lighting is one of the major components of power consumption in less affluent rural households. Many rural houses use kerosene lamps, lanterns, candles and inverter-based electric lamps as a light source. Therefore, artificial lighting in a rural scenario is expected to have certain characteristics such as a) illumination; b) Low cost; c) Low power appropriate consumption; d) Long life; e) Low maintenance. Light-emitting Diode (LED) has been a revolution in such scenarios with its long life, low cost, less power consumption and lesser pollution. While nowadays, low-cost white (cool daylight) LED lights have overtaken the Indian lighting market and are projected to reach $2.2billion by 2021. However, some reports have raised concern regarding various health hazards (circadian rhythm disruption and harm to the human eyes) due to sharp blue-peak in LED lights. Since the scientific literature is still inconclusive about the photo-biological safety of blue-rich white LEDs, usage of LEDs needs more awareness. The aim of this study is to assess the fraction of radiation in the blue region of the entire spectrum of white LED lights and propose low-cost filters to reduce the blue-rich components of LED lighting.

    关键词： Domestic Lighting,Rural Context,Light-Emitting Diode

    更新于2025-09-23 15:21:01

  • YAG:Ce <sup>3+</sup> Transparent Ceramic Phosphors Brighten the Next-Generation Laser-Driven Lighting

    摘要： Y3Al5O12:Ce3+ (YAG:Ce3+) transparent ceramic phosphors (TCPs) are regarded as the most promising luminescent converter for laser-driven (LD) lighting. High-quality YAG:Ce3+ TCPs are still urgent for high efficiency LD lighting devices. YAG:Ce3+ TCPs in a vacuum ambience by using nano-sized raw materials are prepared. Controlling defects by adding nano-sized MgO and SiO2 simultaneously enables a high transmittance nearly 80%. After annealing in air furthermore, the luminous efficiency is enhanced greatly from 106 to 223 lm W?1, which is the best result reported now for LD lighting. These results demonstrate that the optimizing YAG:Ce3+ TCPs in a fitting strategy will brighten once again in the next-generation LD lighting. Based on scanning electron microscopy (SEM) coupled with a cathodoluminescence system, defects and Ce3+ distributions in grains are identified directly for the first time.

    关键词： cathodoluminescence,laser-driven lighting,transparent ceramic phosphors,Mg2+–Si4+,YAG:Ce3+

    更新于2025-09-23 15:21:01

  • [IEEE 2018 IEEE 3rd International Conference on Cloud Computing and Internet of Things (CCIOT) - Dalian, China (2018.10.20-2018.10.21)] 2018 IEEE 3rd International Conference on Cloud Computing and Internet of Things (CCIOT) - Study on LED Color Mixing for Stage Lighting Based on Locus Fitting of Blackbody

    摘要： Aiming at overcoming the defects of basic lighting color rendering for LED stage lighting, this paper establishes a new mixing light method with RGBW four-color mixing model. Compared with traditional tricolor light mixing model, it uses the mixing light of white as the fourth input, with the three-basic color of red, green and blue to obtain a new mixing method. Then the original coefficients of RGBW are optimized after adjusting the two parameters of relative spectral power distribution and illuminance of mixing light for locus fitting of blackbody. Finally, better color rendering of white light can be acquired. By the MATLAB simulation and field testing, experimental results have shown that the proposed method will achieve ideal LED lighting performance, which is convenient for color management of lighting control system in modern theatre.

    关键词： LED stage lighting,CRI,RGBW four-color mixing model,the blackbody locus fitting

    更新于2025-09-23 15:21:01

  • [IEEE 2019 11th Electrical Engineering Faculty Conference (BulEF) - Varna, Bulgaria (2019.9.11-2019.9.14)] 2019 11th Electrical Engineering Faculty Conference (BulEF) - Experimental study of LED luminaire for Human Centric Lighting

    摘要： The article examines an experimental installation with a Human Centric Lighting illuminator to find out if new technologies such as Tunable White and Dali Device Type 8 meet the requirements for accurate and smooth change in the radiated color temperature of the illuminator. To this end, a number of real-time measurements have been carried out and analyzed. The measurement results are summarized in the graphs for the illuminator investigated

    关键词： Dali Device Type 8 (DT8),LED luminaire,Human Centric Lighting (HCL),Tunable White

    更新于2025-09-23 15:21:01

  • High Emission Quantum Yield Tb <sup>3+</sup> -Activated Organic-Inorganic Hybrids for UV-Down-Shifting Green Light-Emitting Diodes

    摘要： Solid-state light-emitting diodes (LEDs) are driving the lighting industry towards efficient and environmentally friendly lighting and displays. Current challenges encompass efficient and low-cost down-shifting phosphors with tuned emission colors. Green light lies on the low-loss optical transmission window in plastic optical fibers and plays a special role in human and plants circadian rhythm regulation. Moreover, green-emitting phosphors may suppress the ‘green gap’ found in semiconductor-based LEDs. In this work, a UV-photostable Tb(NaI)3(H2O)2, with (1-ethyl-1,4-dihydro-7-methyl-4-oxo-1,8-NaI= nalidixic naftiridine-3-carboxylic acid), was incorporated into tripodal organic-inorganic hybrid materials. The hybrid hosts boost the absolute emission quantum yield from ~0.11 (isolated complex) to ~0.82 (doped hybrid), being the largest value reported for Tb3+-based hybrid phosphors. A green-emitting LED was fabricated by coating a near-UV LED (365 nm) with a Tb3+-activated organic-inorganic hybrid showing pure-green light with Commission International de l’Eclairage color coordinates and an efficacy value of (0.33, 0.59) and 1.3 lm·W?1, respectively.

    关键词： near-UV light-emitting diodes,green light-emitting diodes,lanthanides,solid-state lighting,organic-inorganic hybrids

    更新于2025-09-23 15:21:01

  • Estimating the relative contribution of streetlights, vehicles, and residential lighting to the urban night sky brightness

    摘要： Under stable atmospheric conditions the brightness of the urban sky varies throughout the night following the time course of the anthropogenic emissions of light. Different types of artificial light sources (e.g. streetlights, residential, and vehicle lights) have specific time signatures, and this feature makes it possible to estimate the amount of brightness contributed by each of them. Our approach is based on transforming the time representation of the zenithal night sky brightness into a modal expansion in terms of time signatures of the different sources of light. The modal coefficients, and hence the absolute and relative contributions of each type of source, can be estimated by means of a linear least squares fit. A practical method for determining the time signatures of different contributing sources is also described, based on wide-field time-lapse photometry of the urban nightscape. Our preliminary results suggest that, besides the dominant streetlight contribution, artificial light leaking out of the windows of residential buildings may account for a significant share of the time-varying part of the zenithal night sky brightness at the measurement locations, whilst the contribution of the vehicle lights seems to be significantly smaller.

    关键词： streetlights,urban night sky brightness,vehicles,light pollution,time-lapse photometry,residential lighting

    更新于2025-09-23 15:21:01

  • THE EFFECTS OF CONTINUOUS LIGHTING (CL) METHOD ON THE GROWTH DEVELOPMENT OF BRASSICA CHINENSIS FOR LED PLANT FACTORY IN WSN APPLICATION

    摘要： This study was performed to investigate the best practise on using LED light for optimum growth of Brassica Chinensis and reduce turn around time at different kind of photoperiod study utilizing Wireless Sensor Network (WSN) technology as remote monitoring system. Growth performance of Brassica Chinensis under two different wavelengths (blue and red) 16:4 as light source has been used to determine plant growth performance and phytochemicals aspect of plant characteristics. Two experiments were conducted which is the pulse treatment (1 hour light and 1 hour dark) and continuous light (CL) photoperiod treatment in both trials. Observation such as leaves count, height, dry weight and chlorophy I & ll of both plants were analysed. It was noted that the CL photoperiod has significant effect on overall growth performance and remarkably lead to improve the efficiency of the plant factory. In order to reason on data and monitor the environmental parameters of the plant factory, an intelligent system using embedded system has been developed to automate the LED control and manipulation. The result shows that the system is stable and has referential significantly in the area of plant factory or indoor farming system.

    关键词： LED Light Spectrum,Intelligent Control Farming,Continuous Lighting,Sensor,Indoor Farming,Wireless Sensor Network,Plant Factory

    更新于2025-09-23 15:21:01

  • Enlightening Possibilities: Plastics Expand Role in Vehicle Lighting Applications

    摘要： Automotive lighting is something that few people spend much time thinking about—that is until something stops working or someone’s eyes are blasted by another car’s high beams at night. While lighting is rarely the reason people buy cars, it plays an important safety role in all personal and commercial vehicles—both in terms of making a vehicle more visible to humans and animals as well as improving a driver’s ability to see potential problems in the vehicle’s path. Not surprisingly, plastics play an important role in these applications and, in fact, are being used for visual branding on many passenger vehicles. Nominations for the SPE Automotive Innovation Awards Competition—organized by the SPE Automotive Division—show just how innovative lighting has become for increasing occupant comfort and safety, adding functionality, and making vehicles memorable to consumers.

    关键词： PC,Safety,Automotive lighting,Plastics,LED,PMMA,Visual branding,LCP

    更新于2025-09-23 15:21:01