Готові списки джерел за темами / LED lighting diodes

Зміст

Статті в журналах
Дисертації
Книги
Частини книг
Тези доповідей конференцій
Звіти організацій

Добірка наукової літератури з теми "LED lighting diodes"

Автор: Grafiati

Опубліковано: 8 червня 2022

Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями

Оберіть тип джерела:

Ознайомтеся зі списками актуальних статей, книг, дисертацій, тез та інших наукових джерел на тему "LED lighting diodes".

Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.

Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.

Статті в журналах з теми "LED lighting diodes"

Koksal, Nezihe, Meral Incesu, and Ahmet Teke. "Supplemental LED lighting increases pansy growth." Horticultura Brasileira 33, no. 4 (September 18, 2015): 428–33. http://dx.doi.org/10.1590/s0102-053620150000400004.

Повний текст джерела

Анотація:

ABSTRACT: Pansy (Viola cornuta) is a facultative long-day plant that flowers from October until March in Turkey. During the winter months, low light levels can limit plant growth and development. Light emitting diodes (LEDs) can provide supplemental lighting in greenhouses which produce same light intensity with less energy than conventional incandescent lighting. Light emitting diode technologies have enabled affordable and efficient light systems to be installed in greenhouses and plastic tunnels in the field. In this experiment we evaluated the effects of supplemental red-orange LED lightening on the growth and development of pansy cv. Blue Blotch grown in plastic tunnels. The energy, which LEDs are to consume, was provided through a solar panel system with the aim of drawing attention to the cleanliness of solar energy source. Five hours of supplement LED lighting was applied after dusk starting from November to February. Pansy growth and development parameters were compared with non-light supplied control plants. Supplemental LED lighting significantly increased plant biomass weight, flower number and leaves number at the rate of 52%, 72%, and 47%, respectively. Moreover, LED lighting increased plant growth rate (0.109 and 0.306 g of fresh weight), compared with the no light control. LED lighting, however, had no effect on length of stems, number of branches and the diameter of flowers. Thus, this study indicated that pansies are light limited during the winter months and supplemental LED lighting can significantly increase pansy growth and development.

Стилі APA, Harvard, Vancouver, ISO та ін.

Aladov, Andrey V., Alexander L. Zakgeim, Julia V. Semyashkina, and Anton E. Chernyakov. "Dynamically Controlled LED Luminaire for Contrast Visualisation of Biological Tissues During Surgical Procedures." Light & Engineering, no. 06-2021 (December 2021): 144–50. http://dx.doi.org/10.33383/2021-059.

Повний текст джерела

Анотація:

The article reviews the main theoretical, engineering and technological, circuit-engineering and software aspects of development of a dynamically controlled luminaire based on light emitting diodes for contrast visualisation of biological tissues during surgical procedures. The design concept of such surgical luminaire is proposed, which combines high-quality white lighting and coloured accent lighting increasing the contrast of visualisation of particular tissues and borders between them. The calculation model of the luminaire optical system allows maximising the level of illumination and uniformity of illuminance and colour of the surgical area. The software of the luminaire allows to independently modifying intensity of radiation of six coloured light emitting diodes with blue (460 nm), turquoise (505 nm), green (530 nm), green-yellow (550 nm), orange (590 nm) and red (630 nm) light colours for synthesis of coloured lighting of virtually any chromaticity. The level of general lighting by means of phosphor light emitting diodes can also be varied within a wide range. Chromaticity and level of lighting are adjusted by means of pulse-duration modulation of light emitting diode current and the light parameters of the luminaire are controlled by a remote computer via a radio channel. This medical luminaire is primarily designed for lighting during surgical procedures and it can also be used for visual diagnostics based on the colour of analysed tissues.

Стилі APA, Harvard, Vancouver, ISO та ін.

Pakhomova, E. E., and V. P. Gorkin. "LED lighting of automobiles and tractors." Izvestiya MGTU MAMI 7, no. 1-1 (January 10, 2013): 153–58. http://dx.doi.org/10.17816/2074-0530-68275.

Повний текст джерела

Анотація:

The article considers the possibilities of application of high-brightness semiconductor light-emitting diodes in lighting systems of automobiles and tractors. There are shown the main parameters of LEDs and circuit diagrams of their connection.

Стилі APA, Harvard, Vancouver, ISO та ін.

SHUR, MICHAEL, and ARTURAS ŽUKAUSKAS. "LIGHT EMITTING DIODES: TOWARD SMART LIGHTING." International Journal of High Speed Electronics and Systems 20, no. 02 (June 2011): 229–45. http://dx.doi.org/10.1142/s012915641100657x.

Повний текст джерела

Анотація:

We review the history and state-of-the-art of light emitting diode (LED). Unique properties of LEDs– high efficiency, long life time, flexibility in obtaining customized spectral power distribution, fast modulation rate, compact form factor, ability to generate radiation with wavelengths outside the visible range (infrared and ultraviolet, including deep ultraviolet) enable multiple applications for signage, display, general lighting, biology, medicine, agriculture, communications, industrial controls, security, and transportation. Many of emerging LED applications will be in "smart lighting", which are applications that are not possible or difficult to achieve using more traditional lighting sources.

Стилі APA, Harvard, Vancouver, ISO та ін.

Sun, Ching-Cherng, Shih-Hsin Ma, and Quang-Khoi Nguyen. "Advanced LED Solid-State Lighting Optics." Crystals 10, no. 9 (August 27, 2020): 758. http://dx.doi.org/10.3390/cryst10090758.

Повний текст джерела

Анотація:

Light-emitting diodes (LEDs) have been intensively studied for white-light lighting since their luminous efficacy exceeds 50 lm/W. Currently, the luminous efficacy of an LED light tube/bulb is almost above 100 lm/W. LED solid-state lighting (SSL) has unequivocally become the major light source in general lighting. The fact of high efficiency and other advantages of LED SSL is enough to penetrate all lighting scenarios. However, what people demand from new-generation lighting is not only in energy efficiency but also in lighting quality. Thus, how to make the lighting more user friendly is one of the important issues, and, here, optics is the key point. For making a collection with the discussions of the novel optical design in enhancing lighting efficiency in a more uniform illumination pattern, in higher sharpness for special lighting, in a higher signal-to-noise ratio for communication, in more functions for new applications, etc., this Special Issue of “Advanced LED Solid-State Lighting Optics” focuses on advanced applications in all aspects.

Стилі APA, Harvard, Vancouver, ISO та ін.

Kolesnyk, A. "Optical System for Led Luminaire." Metrology and instruments, no. 4 (September 7, 2019): 62–67. http://dx.doi.org/10.33955/2307-2180(4)2019.62-67.

Повний текст джерела

Анотація:

Lighting devices are an important element of a large number of technical systems, including road, living, industrial lighting, lighting systems of vehicles. It is known that the light instrument must fulfill two basic lighting tasks: to redistribute the light source of light source in the right way and to limit its dazzling effect. The introduction of light-emitting diodes (LEDs) for lighting necessitated a completely new quality in the construction of luminaires. The different production technology required new methods and designing tools. It also challenged designers with new problems to solve. LEDs are light sources emitting in one hemisphere, which requires a special approach to designing an LED lighting unit. However, for the illumination of premises with high spans or streets, roads such a light distribution is not suitable. For luminaires with solid-state light sources, other materials and new technology must be used; moreover, light distribution needs to be formed using different methods. This paper presents the design process of a LED luminaire from concept to implementation, exemplified by road lighting, and describes the methods and procedures used by the designer. Also, technological problems influencing the quality of the above lighting are addressed. Optical systems for LEDs are considered. The peculiarities of the use of secondary optical elements in the form of lenses for purpose of obtaining different diagrams of the spatial distribution of light intensity of light-emitting diodes are analyzed. Features and problems of calculation of secondary optical systems are considered. Massive collimators do not have to be elements that focus a narrow beam of light. They are able to form a beam in accordance with any accepted distribution that is appropriate for a given application. They are also able to form a beam in a specific way that is required for outdoor lighting luminaires. The stages of a project for designing a road luminaire require the application of the knowledge and experience gained in various research projects. The design methods described in this paper have been developed designing activity and are also to be used successfully in lighting production.

Стилі APA, Harvard, Vancouver, ISO та ін.

Morrow, Robert C. "LED Lighting in Horticulture." HortScience 43, no. 7 (December 2008): 1947–50. http://dx.doi.org/10.21273/hortsci.43.7.1947.

Повний текст джерела

Анотація:

Solid-state lighting based on the use of light-emitting diodes (LEDs) is potentially one of the biggest advancements in horticultural lighting in decades. LEDs can play a variety of roles in horticultural lighting, including use in controlled environment research, lighting for tissue culture, and supplemental and photoperiod lighting for greenhouses. LED lighting systems have several unique advantages over existing horticultural lighting, including the ability to control spectral composition, the ability to produce very high light levels with low radiant heat output when cooled properly, and the ability to maintain useful light output for years without replacement. LEDs are the first light source to have the capability of true spectral composition control, allowing wavelengths to be matched to plant photoreceptors to provide more optimal production and to influence plant morphology and composition. Because they are solid-state devices, LEDs are easily integrated into digital control systems, facilitating special lighting programs such as “daily light integral” lighting and sunrise and sunset simulations. LEDs are safer to operate than current lamps because they do not have glass envelopes or high touch temperatures, and they do not contain mercury. The first sustained work with LEDs as a source of plant lighting occurred in the mid-1980s to support the development of new lighting systems to be used in plant growth systems designed for research on the space shuttle and space station. These systems progressed from simple red-only LED arrays using the limited components available at the time to high-density, multicolor LED chip-on-board devices. As light output increases while device costs decrease, LEDs continue to move toward becoming economically feasible for even large-scale horticultural lighting applications.

Стилі APA, Harvard, Vancouver, ISO та ін.

Hytönen, T., P. Pinho, M. Rantanen, S. Kariluoto, A. Lampi, M. Edelmann, K. Joensuu, et al. "Effects of LED light spectra on lettuce growth and nutritional composition." Lighting Research & Technology 50, no. 6 (March 28, 2017): 880–93. http://dx.doi.org/10.1177/1477153517701300.

Повний текст джерела

Анотація:

Year-round greenhouse production in northern latitudes depends on the use of artificial lighting. Light emitting diodes provide a promising means to save energy during cultivation as well as to modify the light spectrum to regulate the growth and quality of the crop. We compared the effects of light emitting diode lighting with different spectral compositions on the growth, development and nutritional quality of lettuce ( Lactuca sativa L. ‘Frillice’). We show that warm-white and warm-white supplemented with blue spectra provide equal growth and product quality compared to conventional high-pressure sodium lighting in the absence and presence of daylight. Our data indicate that for biomass accumulation, the far-red component in the light spectrum is more critical than green light or the red/blue ratio. Furthermore, we demonstrate that a red + blue spectrum increases the concentration of several vitamins in lettuce. However, biomass accumulation using this spectrum was insufficient when daylight was excluded.

Стилі APA, Harvard, Vancouver, ISO та ін.

Chen, William, Ka Wai Eric Cheng, and Jianwei Shao. "Circuit Topology Analysis for LED Lighting and its Formulation Development." Energies 12, no. 21 (November 4, 2019): 4203. http://dx.doi.org/10.3390/en12214203.

Повний текст джерела

Анотація:

Light emitted diode (LED) is becoming more popular in the illumination field, and the design of LED lighting is generally made to provide illumination at lower power usage, helping save energy. A power electronic converter is needed to provide the power conversion for these LEDs to meet high efficiency, reduce components, and have low voltage ripple magnitude. The power supply for LED is revisited in this paper. The LEDs connected in series with diode, transistor, or inductor paths are examined. The formulation for each of the cases is described, including the classical converters of buck, boost, buck–boost, and Ćuk. The circuit reductions of the classic circuit, circuit without the capacitor, and without a freewheeling diode are studied. Using LED to replace freewheeling diodes is proposed for circuit component reduction. General equations for different connection paths have been developed. The efficiency and output ripple amplitude of the proposed power converters are investigated. Analytical study shows that the efficiency of proposed circuits can be high and voltage ripple magnitude of proposed circuits can be low. The results show that the proposed circuit topologies can be easily adapted to design LED lighting, which can meet the criteria of high efficiency, minimum components, and low-voltage ripple magnitude at the same time.

Стилі APA, Harvard, Vancouver, ISO та ін.

Liu, Hailiang, Jiade Cheng, and Asnidar Hanim Yusuf. "Design of Light Emitting Diodes (LEDs) Lighting System and Its Application in Garden Landscape Decoration." Journal of Nanoelectronics and Optoelectronics 15, no. 6 (June 1, 2020): 734–42. http://dx.doi.org/10.1166/jno.2020.2793.

Повний текст джерела

Анотація:

Light Emitting Diode (LED) is widely used in garden landscape decoration because of its small size, low power, concentrated light, and the capability of showing more vivid colors. While designing the LED lighting system, considering that a single Advanced RISC Machine (ARM)-based control system cannot achieve large-scale LED display, and a single Field Programmable Gate Array (FPGA)-based control system cannot control the lighting system well, an LED system with the combination of ARM processor-FPGA is proposed. In this system, the ARM processor is used as the major control component. The Linux system realizes remote monitoring and intelligent management of image data. In addition, FPGA is used for LED data output. The lighting system consists of a major control node and a lighting node. The nodes are connected in parallel through a chain network. The major control node uses an ARM Cortex processor and is equipped with a Linux operating system. The lighting node uses ARM + FPGA hardware architecture. During the experiments, the LED lighting system is tested first. The results show that the reading and writing speed is fast. The LED display screen meets the lighting requirements. This LED lighting system is used for night lighting of garden landscapes. During the brightness test, the brightness of lighting objects and the background is used as research objects. Experiments have proved that the ratio of the lighting object brightness to the background brightness between (Yu, M. and Li, X., 2012. A little current k-factor method for measuring junction temperature of aviation lighting power led. Guangxue Jishu/Optical Technique, 38(3), pp.371–375; Monas, A., Verma, A., Gawari, A. and Paswan, R. S., 2016. Portable network monitor using arm processor. Procedia Computer Science, 92, pp.493–497.) is suitable for night lighting of garden landscape decoration, which will not bring discomfort to people who enjoy night scenery.

Стилі APA, Harvard, Vancouver, ISO та ін.

Більше джерел

Дисертації з теми "LED lighting diodes"

Freymiller, Aaron Troy. "LED shipboard lighting a comparative analysis." Thesis, Monterey, California : Naval Postgraduate School, 2009. http://edocs.nps.edu/npspubs/scholarly/theses/2009/Dec/09Dec%5FFreymiller.pdf.

Повний текст джерела

Анотація:

Thesis (Master of Business Administration)--Naval Postgraduate School, December 2009.
Thesis Advisor(s): Dew, Nicholas. Second Reader: Hudgens, Bryan. "December 2009." Description based on title screen as viewed on January 28, 2010. Author(s) subject terms: Lighting, LEDs, shipboard lighting. Includes bibliographical references (p. 31-32). Also available in print.

Стилі APA, Harvard, Vancouver, ISO та ін.

Chan, Ho-kan, and 陳可芹. "Life cycle assessment of LED road lighting." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2012. http://hub.hku.hk/bib/B48542611.

Повний текст джерела

Анотація:

It is observed that the power consumption of road lighting is increased with the length of trafficable road in Hong Kong. The energy used in road lighting is increasing, which means that the greenhouse gases (GHGs) emitted from power plant for generating electricity for road lighting is at the same time increasing. To compare the performance of light emitted diode (LED) road lighting with road lighting of other lamp sources, literature review, life cycle assessment (LCA) and technical assessment are adopted to give an overall comparison. This research focuses more on the environmental impacts of road lighting. LCA is adopted in order to give a comprehensive view on the environmental impact of road lighting. A total of 3 different lamp sources are compared: high pressure sodium (HPS) lamp, induction lamp and light emitted diode (LED) lamp. From the model result, it is found that due to the low power consumption and long life time, LED and induction lamp road lighting gives generally less environmental impact than HPS road lighting. As induction lamp has a longer life span than LED, the environmental impact of induction lamp road lighting is found slightly less than that of LED road lighting. Taking account the future development in LED technology, leading to longer life time, higher efficacy and lower production cost, LED road lighting is expected to be a replacement for road lighting in Hong Kong for the future.
published_or_final_version
Environmental Management
Master
Master of Science in Environmental Management

Стилі APA, Harvard, Vancouver, ISO та ін.

Cizek, Christopher J. "Shipboard LED lighting a business case analysis." Thesis, Monterey, California : Naval Postgraduate School, 2009. http://edocs.nps.edu/npspubs/scholarly/theses/2009/Dec/09Dec%5FCizek.pdf.

Повний текст джерела

Анотація:

Thesis (Master of Business Administration)--Naval Postgraduate School, December 2009.
Thesis Advisors: Dew, Nicholas ; Mutty, John. "December 2009." Description based on title screen as viewed on January 26, 2010. Author(s) subject terms: LED lighting, solid state lighting, business case analysis. Includes bibliographical references (p. 81-83). Also available in print.

Стилі APA, Harvard, Vancouver, ISO та ін.

Li, Sinan, and 李思南. "Several reliability issues and solutions for LED lighting system." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hdl.handle.net/10722/197552.

Повний текст джерела

Анотація:

This thesis presents a study on several reliability issues for LED lighting systems. Firstly, a full survey on exsiting LED ballast has been conducted, and critical design challenges are classified on power level basis (low/ middle/ high power). Specifically, reliability issues have been highlighted, and three major factors have been stipulated: issue of electrolytic capacitor; issue of current imbalance in parallel LED strings; issue of LED junction temperature. The information revealed in the whole survey provide important design criteria for existing LED system designs and guidance for further research directions by pointing out the critical design problems. Two possible solutions for Electrolytic-Capacitor-Less LED Ballasts are proposed regarding the first reliability issue. A series of novel passive LED ballasts are proposed. They are found to be suitable for outdoor applications, such as street lighting applications, where the ability to withstand extreme weather conditions are of major concern. When compared with those in switched mode power supplies, these passive ballasts have good power factor performance and comparatively high efficiency. In addition, an active solution has been developed for indoor applications. Its circuit topology is derived from existing differential inverter topologies and inherits same merits such as simple structure, reduced size, and low cost. Self-configurable current-mirror techniques have been derived and developed afterwards to cope with the current imbalance issue for system with parallel LED strings. In contrast with traditional current sharing methods (either linear type or switched type), the proposed techniques offer a simple solution without the need of independent current references, complicated controllers and auxiliary power supplies. These features are favored by outdoor applications and such re-configurable mirror circuits are originally designed for passive LED ballast as post-current regulators. The techniques are further extended with the ability to tolerate possible circuit failure, such as short circuit and open circuit fault. Then, a new non-contact method for the measurement of both junction-to-case thermal resistance and junction temperature in a LED device has been proposed, with respect to the third reliability issue. Traditionally the direct measurement of junction temperature in LED is not easy without the help of sophisticated methods such as laser or expensive equipment like TeraLED Transient Thermal Tester system. In contrast, the proposed method requires only the external LED power, luminous flux, and heatsink temperature information. The method can be further adopted as a simple tool by engineers to check the internal temperature states in a practical LED system for regulation and evaluation purpose. Finally, a thermal design methodology has been developedfor an LED street lamp system powered by a weakly regulated renewable small power grid. It has been successfully incorporated in the proposed passive LED ballast, such that the LED system can provide the least output luminous fluctuation against line voltage variation. It is envisaged that, with the proposed design methodology, such lighting system will not only provide high reliability, with potential lifetime exceeding 10 years, but with a proven feature of reduced light fluctuation, furthermore, it is found that the passive LED system can act as a smart load and has the potential of reducing the energy storage requirement for smart grids. These merits are attractive to public lighting systems powered by future renewable power grids.
published_or_final_version
Electrical and Electronic Engineering
Doctoral
Doctor of Philosophy

Стилі APA, Harvard, Vancouver, ISO та ін.

Tuladhar, Looja R. "Resonant power MOSFET drivers for LED lighting /." Connect to resource online, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1264709029.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Solomon, Ramzi, P. Pillay, and A. B. Sebitosi. "An automotive interior lighting application using white light-emitting diodes." Thesis, Cape Town : Cape Town University, 2008. http://hdl.handle.net/10019.1/357.

Повний текст джерела

Анотація:

Thesis (MScEng (Department of Electrical Engineering))--University of Cape Town, 2008.
Energy drives technological societies. Developing countries such as South Africa are caught between the desperate need for economic growth and the emerging obligations to the environment. Efficient technologies can be used to mitigate the impact of these seemingly conflicting requirements in urban and rural environments. In this thesis the commercially available white light-emitting diode (LED) with its inherent efficiency, longevity and mechanical strength, is used to show, that success in energy efficiency can be obtained. Two cases are used to illustrate the need for efficient demand-side technology: the electricity shortages of the Western Cape Province in South Africa and a white LED pilot project in Namulonge, Uganda. The Namulonge Solar-Home System (SHS) is analyzed with the intention of creating a more acceptable general lighting solution. The concept of appropriateness through self-determination is discussed within the context of location-specific information integrated into a design procedure. The major thrust and contribution of this thesis, however, is the design of an interior luminaire for Golden Arrow Bus Services (GABS). This is in part based on the hypothesis that application-specific information will lead to implementation and human-needs success, and is researched, designed, fabricated and then laboratory tested. The biggest challenge to be overcome was the spatial light distribution of the LED array. Thus non-imaging optical lens design became the main focus of this project as it held the key to utilizing available light while conserving the light-systems energy. Circular Fresnel and Linear Fresnel (an adaptation of the concentric design) lenses were designed. Electrical, mechanical and thermal aspects of design are also detailed. Far-field, horizontal plane detection over the specified area is used to best gain the uniformity of distribution. The four criteria namely luminance, illuminance, intensity and étendue (collection efficiency), against which each design and focal length iv configuration is compared to, are extensively explored and eventually lead to a final design. In the first designs, the area of the spatial distribution between 50% and 80% of its relative intensity is collimated. The Hybrid Circular Fresnel and Hybrid Linear Fresnel lenses now redirects the relative intensity in two areas, from 50% to 70% (creating parallel rays) and then from 70% to 100% (away from the central axis), renders a distinct difference is spatial uniformity and a reduction in the peak and offaxis located intensity. All four criteria are met, with a minor adjustment of configuration within the bus internal luminaire spacing, with the hybrid designs. It is proposed that GABS employ polished designs of the Hybrid Circular Fresnel, in any of the configurations, which have collection efficiencies ranging between 64.8% and 78.3%.
Sponsored by the Centre for Renewable and Sustainable Energy Studies, Stellenbosch University

Стилі APA, Harvard, Vancouver, ISO та ін.

Krigel, Arthur. "Ocular toxicity evaluation of LED lighting systems." Thesis, Sorbonne Paris Cité, 2015. http://www.theses.fr/2015USPCB167.

Повний текст джерела

Анотація:

Pas de résumé
The aim of the study was to evaluate in controlled retinal risk LED lighting conditions compared to other common household lighting such as CCFL or CFL, in standard lighting conditions, on different animal species pigmented and non-pigmented. At first, we characterized the conditions of adaptation before enlightenment. We found that housing conditions before the light exposure is a source of artifact. Indeed, the location of the cages in a ventilated cabinet and the period before stalling before illumination generates a variable response to retinal light toxicity. Then, we tested the relative sensitivity of the albino strains and pigmented. After 3 weeks of stabulation, the animals were exposed for 24 hours to cold white LED at a luminance of 6000 lux, with dilation of pupils, and the retinas were examined in a week. In these extreme illumination conditions, retinas showed a significant loss of photoreceptors in superior retina, not only in albino animals, but also in pigmented animals. In another experiment, we tested different luminance in cages provided for this purpose. We have used as control a compact fluorescent lighting at 500 lux, with a homogeneous on the floor of the cage. An illumination of 24 hours dilation was performed after the time of dark adaptation. A luminance of 500 lux is a classic condition of a good visual quality domestic lighting. Unlike a compact fluorescent lighting at 500 lux, white LEDs result in a significant loss of photoreceptor nuclei of retinal pigmented rats (LE) 500 lux with an increasing toxicity in function of the luminance of the LED lighting. Finally, to assess the effects prolonged exposure we exposed the rats for one week or one month, but in alternating illumination only during the day, and without dilated pupils (day / night cycle 12h / 12h, no dilated pupils) with LED different spectra. We have compared these lighting conditions to a compact fluorescent lighting at 500 lux and non-illuminated rats. After one week, only albino rats showed a loss of photoreceptors and only after exposure to blue LEDs. These results show that the blue LEDs are more toxic than the white LEDs confirming the effects of short wavelengths. After 1 month of illumination, a significant loss of photoreceptors is observed in the retinas of non-pigmented rats, not only with the blue LEDs, but also with green LEDs and cool white LEDs. An increase of the exposure time under standard conditions leads to a loss of photoreceptors accumulated suggesting a potentially toxic effect of LED light, not observed with a compact fluorescent lighting even luminance

Стилі APA, Harvard, Vancouver, ISO та ін.

Deng, Wenpeng. "A solar PV-LED lighting system with bidirectional grid ballasting." Thesis, University of Cambridge, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.709190.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Leng, Sovannarith. "Identifying and evaluating aging signatures in light emitting diode lighting systems." Thesis, Toulouse 3, 2017. http://www.theses.fr/2017TOU30035/document.

Повний текст джерела

Анотація:

Dans ce travail, les dégradations des diodes électroluminescentes (DEL) ont été étudiées en identifiant et en évaluant leurs signatures électriques et photométriques en vieillissement accéléré sous stress thermique et électrique. Un prototype de banc de test expérimental a été développé et construit spécifiquement pour cette étude ce qui nous a permis de tester 128 échantillons en appliquant différentes conditions de stress thermiques et électriques. Quatre types différents de DEL ont été étudié avec des caractéristiques techniques similaires (température de couleur, courant nominal, mono-puce,...) mais avec des technologies différentes couvrant les principaux acteurs du marché (Cree, Osram, Philips et Seoul Semiconductor). Les échantillons ont d'abord été caractérisés à leur état initial, puis soumis à des conditions de stress électrique (à 350mA ou 1050mA) et thermique (fixé à 50°C). Les mécanismes de défaillance ont été analysés en étudiant l'évolution des signatures électriques et photométriques. Ces caractérisations ont permis d'évaluer et de déterminer l'origine des dégradations à différents niveaux : puce semi-conductrice, interconnexions, phosphore ou encapsulation du dispositif. Les caractérisations électriques nous ont permis d'identifier les mécanismes de dégradation de la puce semi-conductrice et de déterminer la nature des dégradations au niveau du contact ohmique du dispositif (sous fort courant injecté). Les caractérisations photométriques complètent cette étude en évaluant les dégradations associées à l'optique (encapsulation et packaging)
In this work, the degradation of light emitting diodes (LEDs) is studied by identifying and evaluating their aging signature during the stress time. The custom-made experimental test bench is built for realization of the test measurement. Through this experimental test bench, it allows to test a large amount of LED samples and enable to select different temperature condition and different current stress level. There are four different types of LED with similar characteristic in term of their color temperature, IF, VF, power (1W) and as monochip, but different technology coming from Cree, Osram, Philips and Seoul Semiconductor. The devices are firstly characterized their electrical and photometrical characteristic at their initial state, then they are submitted to different current stress condition at low current stress (350mA) and high current stress (1000mA) while the thermal stress is fixed at one temperature (50°C). The study of these devices failure mechanism is archived by using the primary method based on the electrical and photometrical characterization of the devices that allows to evaluate their degradation at different locations of the device components such as semiconductor chip, interconnection and device's package. The electrical characteristic of the device's I-V curve: at low injected current level and reverse bias allow us to identify the degradation characteristic of device's semiconductor chip, at high injected current level allows us to determine the degradation of device's ohmic contact and photometric characteristic allows us to evaluate the degradation of device's package system

Стилі APA, Harvard, Vancouver, ISO та ін.

Li, Nola. "GaN on ZnO: a new approach to solid state lighting." Diss., Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/33840.

Повний текст джерела

Анотація:

The objective of the research was to develop high quality GaN epitaxial growth on alternative substrates that could result in higher external quantum efficiency devices. Typical GaN growth on sapphire results in high defect materials, typically 10⁸⁻¹⁰cm⁻², due to a large difference in lattice mismatch and thermal expansion coefficient. Therefore, it is useful to study epitaxial growth on alternative substrates to sapphire such as ZnO which offers the possibility of lattice matched growth. High-quality metalorganic chemical vapor deposition (MOCVD) of GaN on ZnO substrate is hard to grow due to the thermal stability of ZnO, out-diffusion of Zn, and H₂back etching into the sample. Preliminary growths of GaN on bare ZnO substrates showed multiple cracks and peeling of the surface. A multi-buffer layer of LT-AlN/GaN was found to solve the cracking and peeling-off issues and demonstrated the first successful GaN growth on ZnO substrates. Good quality InGaN films were also grown showing indium compositions of 17-27% with no indium droplets or phase separation. ZnO was found to to sustain a higher strain state than sapphire, and thereby incorporating higher indium concentrations, as high as 43%, without phase separation, compared to the same growth on sapphire with only 32%. Si doping of InGaN layers, a known inducer for phase separation, did induce phase separation on sapphire growths, but not for growths on ZnO. This higher strain state for ZnO substrates was correlated to its perfect lattice match with InGaN at 18% indium concentration. Transmission electron microscopy results revealed reduction of threading dislocation and perfectly matched crystals at the GaN buffer/ZnO interface showing coherent growth of GaN on ZnO. However, Zn diffusion into the epilayer was an issue. Therefore, an atomic layer deposition of Al₂O₃was grown as a transition layer prior to GaN and InGaN growth by MOCVD. X-ray and PL showed distinct GaN peaks on Al₂O₃/ZnO layers demonstrating the first GaN films grown on Al₂O₃/ZnO. X-ray photoelectron spectroscopy showed a decrese in Zn diffusion into the epilayer, demonstrating that an ALD Al₂O₃layer was a promising transition layer for GaN growth on ZnO substrates by MOCVD.

Стилі APA, Harvard, Vancouver, ISO та ін.

Більше джерел

Книги з теми "LED lighting diodes"

LED lighting. Beijing: O'Reilly, 2012.

Знайти повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

LED lighting: Professional techniques for digital photographers. Buffalo, N.Y: Amherst Media, 2012.

Знайти повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

America, Illuminating Engineering Society of North. Technical memorandum on light emitting diode (LED) sources and systems. New York, NY: Illuminating Engineering Society of North America, 2005.

Знайти повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Zhong hua min guo guang dian xue hui, ed. LED gong cheng shi ji chu gai nian yu ying yong: Fundamental and applications of LED engineers. Taibei Shi: Wu nan tu shu chu ban gong si, 2012.

Знайти повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Guangdong LED chan ye ji cu jin zheng ce yan jiu. Guangzhou: Hua nan li gong da xue chu ban she, 2011.

Знайти повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Lü se zhao ming LED shi yong ji shu. Beijing Shi: Hua xue gong ye chu ban she, 2009.

Знайти повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Liu, S. LED packaging for lighting applications: Design, manufacturing, and testing. Hoboken, N.J: Wiley, 2011.

Знайти повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Lenk, Ron. Practical lighting design with LEDs. Piscataway, NJ: IEEE Press, 2011.

Знайти повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Conway, Kathryn M. Light emitting diodes (LEDs) in lighting and display applications, 2003-2015. Portland, ME: Intertech, 2003.

Знайти повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Khan, T. Q., Q. T. Vinh, P. Bodrogi, and H. Winkler. LED Lighting: Technology and Perception. Wiley & Sons, Incorporated, John, 2014.

Знайти повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Більше джерел

Частини книг з теми "LED lighting diodes"

Ibaraki, Yasuomi. "LED Supplementary Lighting." In Light Emitting Diodes for Agriculture, 27–36. Singapore: Springer Singapore, 2017. http://dx.doi.org/10.1007/978-981-10-5807-3_2.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Bugbee, Bruce. "Economics of LED Lighting." In Light Emitting Diodes for Agriculture, 81–99. Singapore: Springer Singapore, 2017. http://dx.doi.org/10.1007/978-981-10-5807-3_5.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Viršilė, Akvilė, Margit Olle, and Pavelas Duchovskis. "LED Lighting in Horticulture." In Light Emitting Diodes for Agriculture, 113–47. Singapore: Springer Singapore, 2017. http://dx.doi.org/10.1007/978-981-10-5807-3_7.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Dutta Gupta, S., and S. Pradhan. "Regulation of Gene Expression by LED Lighting." In Light Emitting Diodes for Agriculture, 237–58. Singapore: Springer Singapore, 2017. http://dx.doi.org/10.1007/978-981-10-5807-3_10.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

van Iersel, Marc W. "Optimizing LED Lighting in Controlled Environment Agriculture." In Light Emitting Diodes for Agriculture, 59–80. Singapore: Springer Singapore, 2017. http://dx.doi.org/10.1007/978-981-10-5807-3_4.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Naznin, Most Tahera, and Mark Lefsrud. "An Overview of LED Lighting and Spectral Quality on Plant Photosynthesis." In Light Emitting Diodes for Agriculture, 101–11. Singapore: Springer Singapore, 2017. http://dx.doi.org/10.1007/978-981-10-5807-3_6.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Dutta Gupta, S., and A. Agarwal. "Influence of LED Lighting on In Vitro Plant Regeneration and Associated Cellular Redox Balance." In Light Emitting Diodes for Agriculture, 273–303. Singapore: Springer Singapore, 2017. http://dx.doi.org/10.1007/978-981-10-5807-3_12.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Su, Chia-Ying, Chun-Han Lin, Yang Kuo, Yu-Feng Yao, Hao-Tsung Chen, Charng-Gan Tu, Chieh Hsieh, Horng-Shyang Chen, Yean-Woei Kiang, and C. C. Yang. "Surface Plasmon–Coupled Light-Emitting Diodes." In Handbook of Solid-State Lighting and LEDs, 141–60. Boca Raton, FL : CRC Press, Taylor & Francis Group, [2017] | Series: Series in optics and optoelectronics ; 25: CRC Press, 2017. http://dx.doi.org/10.1201/9781315151595-9.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Liu, Jianping, and Hui Yang. "GaN-Based Blue and Green Laser Diodes." In Handbook of Solid-State Lighting and LEDs, 361–91. Boca Raton, FL : CRC Press, Taylor & Francis Group, [2017] | Series: Series in optics and optoelectronics ; 25: CRC Press, 2017. http://dx.doi.org/10.1201/9781315151595-19.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Jou, Jwo-Huei, Meenu Singh, and Yi-Fang Tsai. "Natural Light-Style Organic Light-Emitting Diodes." In Handbook of Solid-State Lighting and LEDs, 481–515. Boca Raton, FL : CRC Press, Taylor & Francis Group, [2017] | Series: Series in optics and optoelectronics ; 25: CRC Press, 2017. http://dx.doi.org/10.1201/9781315151595-23.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Тези доповідей конференцій з теми "LED lighting diodes"

Rahmani Nejad, Akbar, and M. A. Olia. "Semi-cylindrical LED lamp." In Light-Emitting Diodes: Materials, Devices, and Applications for Solid State Lighting XIV. SPIE, 2010. http://dx.doi.org/10.1117/12.845446.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Li, Yun-Li, Tzu-Yang Lin, and Yu-hung Lai. "Development and progress of micro LED display technology (Conference Presentation)." In Light-Emitting Diodes: Materials, Devices, and Applications for Solid State Lighting XXII, edited by Li-Wei Tu, Martin Strassburg, Jong Kyu Kim, and Michael R. Krames. SPIE, 2018. http://dx.doi.org/10.1117/12.2296337.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Kim, Kyoungsik, Changuk Kim, and Seunghwa Baek. "Highly scattering layer for efficient LED light extraction (Conference Presentation)." In Light-Emitting Diodes: Materials, Devices, and Applications for Solid State Lighting XXI, edited by Li-Wei Tu, Martin Strassburg, Jong Kyu Kim, and Michael R. Krames. SPIE, 2017. http://dx.doi.org/10.1117/12.2252513.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Jin, Xiaomin, Gregory Chavoor, and Guobin Liu. "Study of patterned sapphire substrate and SiO2 array in GaN LED." In Light-Emitting Diodes: Materials, Devices, and Applications for Solid State Lighting XXII, edited by Li-Wei Tu, Martin Strassburg, Jong Kyu Kim, and Michael R. Krames. SPIE, 2018. http://dx.doi.org/10.1117/12.2285389.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Lin, Yue, Yi Tu, Yijun Lu, Tingzhu Wu, Zhong Chen, Yao Xiao, and Zhangbao Peng. "An introduction on microscopic-hyperspectral imaging for GaN-based LED investigation." In Light-Emitting Diodes: Materials, Devices, and Applications for Solid State Lighting XXII, edited by Li-Wei Tu, Martin Strassburg, Jong Kyu Kim, and Michael R. Krames. SPIE, 2018. http://dx.doi.org/10.1117/12.2281120.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Lachmayer, Roland, Peer-Phillip Ley, and Marcel Philipp Held. "Analysis of LED arrangement in an array with respect to lens geometry." In Light-Emitting Diodes: Materials, Devices, and Applications for Solid State Lighting XXII, edited by Li-Wei Tu, Martin Strassburg, Jong Kyu Kim, and Michael R. Krames. SPIE, 2018. http://dx.doi.org/10.1117/12.2290253.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Boyd, A. R., H. Behmenburg, O. Feron, Clifford McAleese, James O'Dowd, Arthur Beckers, and Michael Heuken. "Blue LED mass production in a close-coupled showerhead MOCVD tool (Conference Presentation)." In Light-Emitting Diodes: Materials, Devices, and Applications for Solid State Lighting XXI, edited by Li-Wei Tu, Martin Strassburg, Jong Kyu Kim, and Michael R. Krames. SPIE, 2017. http://dx.doi.org/10.1117/12.2249271.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Wang, Kai, Fei Chen, Zongyuan Liu, Xiaobing Luo, and Sheng Liu. "Novel Application-Specific LED Packages Integrated With Compact Freeform Lens." In ASME 2009 InterPACK Conference collocated with the ASME 2009 Summer Heat Transfer Conference and the ASME 2009 3rd International Conference on Energy Sustainability. ASMEDC, 2009. http://dx.doi.org/10.1115/interpack2009-89335.

Повний текст джерела

Анотація:

It has been widely accepted that solid state lighting, in terms of white light emitting diodes (LEDs), will be the fourth illumination sources due to their superior performance. In this study, an effective compact freeform lens design method for LED packaging was introduced. A compact silicone LED packaging lens with the refract index of 1.54 was designed for street lighting based on this method. Integrated with this small lens, a novel application-specific LED package, whose manufacturing process can be easily integrated into current LED packaging processes, was suggested. Two application-specific LED array modules, with the type of chip on board (CoB) package, were also designed by integrating 3×3 freeform silicone and polycarbonate (PC) lens arrays. Numerical simulation results demonstrated that the optical performances of these application-specific LED modules could directly meet the requirements of street lighting. By comparing with the traditional LED illumination module consisting of an LED and secondary optics, the novel application-specific LED packages have the advantages of low profile, small volume, high light output efficiency (LOE), low cost and convenience for customers to use, and they will probably become the trend of LED packages, providing more cost-effective solution to general lighting.

Стилі APA, Harvard, Vancouver, ISO та ін.

Nilsson Tengelin, M., N. Mylly, and P. O. Hedekvist. "ARE THE DEMANDS IN ENTERTAINMENT LIGHTING TOO HIGH FOR WHITE LIGHT EMITTING DIODES?" In CIE 2021 Conference. International Commission on Illumination, CIE, 2021. http://dx.doi.org/10.25039/x48.2021.po04.

Повний текст джерела

Анотація:

This paper reports the result of a survey on entertainment lighting distributed to 246 museums and 56 theatres in Sweden. The questions concerned the lighting technology used, experience from changing lighting systems, plans, problems, apprehensions and expectations. The replies showed that the transition to LED has been much faster in museums than in theaters and 35% of the theatres do not plan for a transition to LED. Reasons given are economy, light quality, and dimming functionality. Lighting professionals are generally sceptical in exchanging halogen lights. The artistic expression in lighting design goes beyond the specifications and what is promised in the data sheet. To facilitate a smoother transition to modern lighting technologies, the quality of the white light and proper function of the luminaires must be ensured and the communication between the manufacturers, retailers, lighting professionals and other artistic functions must be improved.

Стилі APA, Harvard, Vancouver, ISO та ін.

Chung, Shu-Ru, Yu-Sheng Su, and Chih-Chun Hsiao. "Fabrication of CuInS2/ZnS quantum dots-based white light-emitting diodes with high color rendering index." In Sixteenth International Conference on Solid State Lighting and LED-based Illumination Systems, edited by Nikolaus Dietz and Ian T. Ferguson. SPIE, 2017. http://dx.doi.org/10.1117/12.2273135.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Звіти організацій з теми "LED lighting diodes"

Kinzey, B. R., and M. A. Myer. Demonstration Assessment of Light-Emitting Diode (LED) Roadway Lighting. Office of Scientific and Technical Information (OSTI), November 2009. http://dx.doi.org/10.2172/1218419.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Rishman, E. E., and J. R. Tuenge. Demonstration Assessment of Light-Emitting Diode (LED) Freezer Case Lighting. Office of Scientific and Technical Information (OSTI), October 2009. http://dx.doi.org/10.2172/1218418.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Kinzey, B. R., and M. A. Myer. Gateway Demonstration Assessment of Light-Emitting Diode (LED) Roadway Lighting. Office of Scientific and Technical Information (OSTI), August 2009. http://dx.doi.org/10.2172/1218269.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Cook, Tyson, Jordan Shackelford, Megan Johnson, and Terrance Pang. Demonstration Assessment of Light Emitting Diode (LED) Street Lighting, Phase III Continuation. Office of Scientific and Technical Information (OSTI), November 2008. http://dx.doi.org/10.2172/1218243.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Myer, M. A., and R. T. Goettel. Demonstration Assessment of Light-Emitting Diode (LED) Parking Lot Lighting, Phase I. Office of Scientific and Technical Information (OSTI), June 2010. http://dx.doi.org/10.2172/1218561.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Myer, Michael, Bruce R. Kinzey, and Ku'uipo Curry. Demonstration Assessment of Light-Emitting Diode (LED) Parking Lot Lighting in Leavenworth, KS. Office of Scientific and Technical Information (OSTI), May 2011. http://dx.doi.org/10.2172/1016449.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Werner Goetz, Bill Imler, James Kim, Junko Kobayashi, Andrew Kim, Mike Krames, Rick Mann, Gerd Mueller-Mach, Anneli Munkholm, and Jonathan Wierer. Development of Key Technologies for White Lighting Based on Light-Emitting Diodes (LEDs). Office of Scientific and Technical Information (OSTI), March 2004. http://dx.doi.org/10.2172/921943.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Kinzey, Bruce R., and Michael Myer. Demonstration Assessment of Light-Emitting Diode (LED) Street Lighting Host Site: Lija Loop, Portland, Oregon. Office of Scientific and Technical Information (OSTI), November 2009. http://dx.doi.org/10.2172/972973.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Kinzey, Bruce R., and Michael Myer. Demonstration Assessment of Light-Emitting Diode (LED) Roadway Lighting at the I-35W Bridge, Minneapolis, MN. Office of Scientific and Technical Information (OSTI), August 2009. http://dx.doi.org/10.2172/972972.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Richman, Eric E., and Jason R. Tuenge. Demonstration Assessment of Light-Emitting Diode (LED) Freezer Case Lighting in Albertsons Grocery in Eugene, OR. Office of Scientific and Technical Information (OSTI), October 2009. http://dx.doi.org/10.2172/967236.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Ми пропонуємо знижки на всі преміум-плани для авторів, чиї праці увійшли до тематичних добірок літератури. Зв'яжіться з нами, щоб отримати унікальний промокод!