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白光LED技术及进展 总被引:3,自引:0,他引:3
半导体照明是本世纪最具发展前景的高技术领域之一,白光LED将成为21世纪的新一代光源——第四代电光源,可以替代白炽灯、荧光灯和高压气体放电灯等传统光源,白光LED孕育着巨大的商机。本文简介白光LED的基本原理、特点、发展和应用前景。 相似文献
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绿色照明的第4代光源白光LED已开始逐步在家庭照明、公司路照明、移动照明、军事照明、设备照明和汽车照明中得到应用。LED所组成的照明系统正越来越受到人们的重视。本文是大陆近年来照明用白光LED技术发展现状,着重讨论制造白光LED的主要技术途径和关键技术以及发展趋势和市场应用前景。 相似文献
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半导体照明是本世纪最具发展前景的高技术之一,白光LCD将成为21世纪的新一代光源——第四代电光源.可以替代白炽灯、荧光灯和高压气体放电灯等传统光源,白光LED孕育着巨大的商机。本文阐述了LED的基本原理、特点和发展及应用前景,并介绍了白光LED的市场和产业现状。 相似文献
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荧光粉受激发产生的白光LED照明光源存在显色指数较低的问题.对此提出一种利用光谱拟合反演高显指目标光谱的方法,针对已知白光LED计算提高该光源所需补充的单色光LED种类及光谱系数.利用光谱拟合方法分析添加不同波段的光谱对白光LED显指和色温的影响.并通过拟合反演的方法进行补光设计,使用一到两种单色光LED,将冷白光源和中性白光源的显指分别提高至92.3和96.8.实验结果表明,使用红光与蓝绿光、低波长绿光LED补光后,大幅度提高了荧光粉受激发产生的白光LED光源的显色性. 相似文献
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无论是手机还是液晶电视。凡是以LED为背光源的消费类电子产品不断地追求越来越小的背光源的尺寸,以匹配日益变薄的显示器,而且要求LED背光系统制造商用更少数量的LED实现更佳的性能,而且把系统做得更纤细。本文探讨的就是如何在不牺牲亮度以及均匀性的前提上,用背光所需的最少的LED来实现“更薄”的目的。 相似文献
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一种回路热管对大功率LED散热的研究 总被引:1,自引:3,他引:1
针对大功率LED散热能力较其它照明灯具差这一问题,研制了一种应用在多芯片大功率LED散热上的回路热管装置,并研究了热负荷、倾角等对热管的起动性、均温性和热阻等的影响。试验结果表明,所设计的热管散热器的热阻在0.48~1.47K/W之间;在蒸发器倾斜角为0°和30°时,蒸发器的均温性分别被控制在1.5℃和4.3℃以内。因此,将这种结构的热管应用在大功率LED散热系统中时,首先应该对蒸发器倾斜角度对系统散热性能的影响进行测试评估。 相似文献
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半导体照明中的非成像光学及其应用 总被引:28,自引:0,他引:28
以GaN基功率型发光二极管(LED)为代表的半导体照明光源,具有其他传统光源无法比拟的诸多优点,被公认为21世纪最有价值的新型光源。充分发挥功率型LED的优势,利用非成像光学进行面向实际应用的功率型LED封装光学系统设计,以高端半导体照明光源的制造为突破点,带动整个半导体照明产业的快速进步,已成为半导体照明技术发展的战略选择。回顾了非成像光学的历史、研究进展以及在半导体照明中的应用,并通过设计实例,介绍了面向功率型LED光线耦合、二维给定光分布以及三维给定光分布问题的非成像光学系统设计原理与解决方案。 相似文献
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近年来,我国LED产业发展非常迅速,LED也应用得越来越广泛。现在人们已经开始将LED光源应用于照明行业中,本文主要对LED灯在辐射安全方面进行探讨。并对LED灯辐射安全测试方法的研究做了相关介绍。 相似文献
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This paper is on a novel use of lighting or signaling devices constructed by light-emitting diodes (LEDs) as a positioning beacon. The idea is that the surface of the LED lighting device is divided into regions and used to show different visual patterns that are not noticeable by the human eye due to the high-frequency switching of the LEDs. A digital camera is used as a receiver to capture a sequence of images of the LED positioning beacon transmitter. Image-processing algorithms are used to decode the location code that is encoded in the visual patterns transmitted by the LED device. This idea can be applied to any LED traffic lights or signaling devices on the road and turn them into parts of a positioning beacon system. Such a system made up of high-brightness visible LEDs can provide the function of open-space wireless broadcasting of the positioning signal. The LED signaling method, transmission protocol, camera frame rate, LED flash rate, together with an implemented system and the experimental results, are presented in this paper. 相似文献
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Color rendering and luminous efficacy of trichromatic and tetrachromatic LED-based white LEDs 总被引:1,自引:0,他引:1
Zhang Lei Guo Xia Liang Ting Gu Xiaoling Lin Qiao Ming Shen Guangdi 《Microelectronics Journal》2007,38(1):1-6
White light-emitting diode (LED) spectra for general lighting should be designed for high luminous efficacy as well as good color rendering, which are generally in a trade-off relationship. White LEDs have uncountable metameres, they have different luminous efficacy and color rendering. Appropriate designed trichromatic and tetrachromatic LED-based white LEDs are presented that have acceptable color rendering as well as good luminous efficacy. Triachromatic white LEDs, with a wavelength combination of 460, 540, and 615 nm, offer high general color rendering index exceeding 89, and luminous efficacy 336 lm/W. The general color rendering index of tetrachromatic LED-based white LEDs combined from 460, 525, 590, and 640 nm is 95, the luminous efficacy is 306 lm/W. Further analysis shows the changing trends of the luminous efficacy, color rendering and the chromaticity coordinate of the optimized trichromatic and tetrachromatic white LEDs depending on the wavelength shift of the primary LEDs. For the optimized trichromatic white LEDs, both the luminous efficacy and color rendering change more with the wavelength shifts of the primary red LEDs than with the wavelength shifts of the blue and green LEDs. For the optimized tetrachromatic white LEDs, the changes of the luminous efficacy caused by the wavelength shifts of one red LED are smaller than the changes of trichromatic white LEDs. And the wavelength shifts of the red primary LED that have shorter wavelength affect the color rendering more than the other primary LEDs. The wavelength shifts of the blue primary LED change the chromaticity coordinate of the white LEDs more. The small changes of the chromaticity coordinate of the white LED do not mean small changes of the k and Ra. 相似文献
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LED路灯产品质量的提升对策探讨 总被引:1,自引:1,他引:0
我国的LED产业在最近几年发展得很迅速,得到越来越广泛的应用,而将LED光源应用于道路照明中却是一项新兴产业。文中主要探讨台湾颁布的CNS15233标准的要求对国内目前生产的LED路灯在耐久性、配光特性、光效、环境适应性等方面的影响,并总结了LED路灯在设计时需注意的方面,急切呼吁国内有关道路照明灯具性能要求的标准尽快出台。 相似文献
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LED信号灯二次光学设计 总被引:1,自引:0,他引:1
随着科学技术的发展,LED在很多领域中被应用得越来越广泛,如在信号灯中的应用,因此就需要对LED发出的光线进行二次光学设计。文中介绍了一种LED信号灯的二次光学设计思路和方法,通过对光通量的估算,设计出合理的LED分布、光学面罩和菲涅耳透镜。 相似文献
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D.A. van den Ende R.H.L. Kusters M. Cauwe A. van der Waal J. van den Brand 《Microelectronics Reliability》2013
Integration of LEDs on flexible foil substrates is of interest for flexible lighting applications and for backlights for flexible displays. Such a large area lighting device can be made by integrating a matrix of closely spaced LEDs on a flexible foil substrate. Preferably, these LEDs are integrated unpackaged, i.e. as bare dies, as this reduces footprint, thickness and cost. As substrates, low cost materials like polyethylene terephthalate (PET) should preferably be used. However, the use of these materials also imposes limitations. Especially, their low thermal stability limits the maximum temperatures during the processing and the thermal dissipation of the LED during operation will pose constraints on the thermal design. This paper describes the results of research on possibilities for integrating bare die LEDs with such low cost flexible PET foils. Bonding of LED dies on PET substrates with copper circuitry using conductive adhesives was performed. Both anisotropic conducting adhesives and isotropic conducting adhesives were investigated. An experimental comparison is made between the different techniques based on temperature/humidity reliability and flexural stability of the bonded LEDs. Additionally, finite element (FE) thermal modeling results of adhesively bonded LED-on-foil configurations are presented. The role of the different materials and the effect of their geometries on the temperature distribution in the simulated devices are discussed. The results are compared to experimentally observed temperature distributions using infrared thermal imaging in LED on PET foil reference devices. Finally a demonstrator device of 64 LEDs on flexible copper–PET substrate is presented. 相似文献