Light-emitting Diode Lighting Technology Research Articles

Leading Light: The Impact of Advanced Lighting Technologies on Indonesia's Office Industry

Addressing concerns over resource scarcity and environmental sustainability necessitates a global shift towards sustainable energy, notably facilitated by adopting Light-Emitting Diode (LED) lamps. This transition is pivotal for ensuring global energy security and aligning with sustainability goals. This study endeavors to comprehensively analyze potential energy savings achievable through the transition from Fluorescent (FL) lamps to LED lamps within industrial offices. Emphasis is placed on highlighting the central role of energy efficiency. Utilizing false color rendering as a visual guide, the study systematically identifies areas where FL lamps inadequately illuminate. The findings prompt recalculations for determining optimal room illumination achievable through implementing LED lamps. Lux calculations are then employed to showcase the superior illumination offered by LED lamps, revealing consistent monthly cost savings of 35%, particularly when harmonized with Building Management System (BMS) control in industrial office buildings. The study's results indicate that LED lamps provide superior illumination, yielding a noteworthy 35% monthly cost savings, especially when integrated with BMS control. Lamps contribute modestly (21-30%) to overall energy consumption, while air conditioning commands a substantial 60%, underscoring the critical need for advanced lighting technology. This need is emphasized, particularly with Solar PV as a sustainable energy source. Understanding technological developments, especially in BMS, is crucial to optimize energy efficiency in industrial offices. The imperative implementation of LED lighting technology is a critical solution to address resource scarcity and environmental concerns in industrial offices. The efficacy of LED lamps in achieving significant energy savings, especially when coupled with advanced systems like BMS and complemented by renewable energy sources such as Solar PV. The conclusion stresses the significance of staying abreast of technological advancements to foster sustained progress towards energy-efficient and environmentally conscious practices within industrial environments.

Near-Field LED Illumination Strategies for Tonsillectomy and Adenoid Surgery.

Objective: Perform a pilot feasibility study to demonstrate viability, quality, and safety advantages of light-emitting diode (LED) illumination when performing tonsillectomy. Study Design: Prospective cohort. Setting: Children's Hospital and Community Multispecialty Hospital. Methods: We tested a commercially available LED light, held in position with a minimally modified mouth gag, for off-label use in a "cavernous wound." We assessed surgeons', residents', and nurses' perceptions of function, safety, as well as preferences compared to headlights. Results: The light was used in 30 cases. Noted advantages over traditional lighting methods included superior brightness, stability and consistency of illumination, and the ability for others to assist more quickly. The inability to adjust brightness and/or the angle of light was an observed disadvantage. A small oral cavity or large tonsillar pillars creating a shadow required the temporary addition of a headlight. However, LED light use was not discontinued. Surgeons and residents reported a preference for not wearing a headlight, and nurses expressed concerns about headlight cleanliness. Conclusion: LED lighting technology demonstrated utility for teaching surgeons, residents, and nurses, and was perceived as safe. Additional specifications may make the light applicable to a wider variety of cases and could potentially mitigate headlight use during procedures of the oral cavity and oropharynx.Level of Evidence: 4.

Consumer reaction to indoor farming using LED lighting technology and the effects of providing information thereon

Indoor vertical farming using artificial light has gained popularity as one solution to food problems. However, prior studies have shown that some consumers have a negative impression that crops are grown in an artificial environment. The increased use of purple Light-Emitting Diode (LED) lighting, which would make the growing environment look more artificial, may exacerbate that negative perception, leading to low acceptance of vertically farmed produce. Given that consumers are increasingly seeing indoor vertical farming directly, for example, in supermarkets and office buildings, it is important to understand how they perceive the use of purple LED lighting to grow crops and whether these perceptions can be improved by learning more about the scientific basis for artificial light cultivation. This study aimed to determine whether purple LED lighting reduces consumers’ perceptions of indoor vertical farming compared to traditional white lighting, and to examine whether providing information on plant growth and artificial light changes those perceptions. We administered a web-based questionnaire to 961 Japanese respondents, and analyzed the response data using analysis of variance and an ordered probit model to explore the factors that define the likability for indoor vertical farming. The results revealed that the color of LED lighting had a limited influence on consumers' perceptions of indoor vertical farming, whereas explaining the principle of plant growth under artificial light improves their perceptions. Additionally, personal factors, such as resistance to novel food technology, trust in food safety, and awareness of indoor vertical farming, had a significant impact on the perceptions. It is crucial to expand opportunities for people to interact with artificial light cultivation and disseminate information about its scientific mechanisms.

Effects of LED Lighting Technology on Morphology, Antioxidant activity, and the Bioactive Compounds Accumulation of Anoectochilus burmannicus in the Greenhouse System

Anoectochilus burmannicus is valued for medicinal and ornamental purposes. It is characterized by beautiful foliage with attractively red-purple with bronze-colored veins blotches. Kinsenoside is an active compound in A. burmannicus which provided anti-inflammation properties, anti-obesity, and anti-diabetes properties. This study aimed to investigate the effects of light-emitting diode (LED) light quality on growth, photosynthetic pigment content, antioxidant activities, and the accumulation of bioactive compounds (polysaccharides, phenolics, and flavonoids) in A. burmannicus. Plants of A. burmannicus were grown under 6 different LED lighting in the greenhouse system for 60 days. The 6 treatments were blue light (BL, 24 h), cool light (CL, 24 h), natural light (NL, 12 h), red:blue 1:1 light (RBL, 24 h), red light (RL, 24 h), and warm light (WL, 24 h). The results showed that A. burmannicus plants have a positive effect on the growth and bioactive compounds under LED lights (24 h) technology compared to natural light (12 h). The WL treatment had the most positive effect on morphological parameters, while the BL treatment showed an enhancement in fresh weight and dry weight. NL treatment is increased the Chlorophyll a and Chlorophyll b content. The Carotenoid content increased in the RBL treatment phenolics content was considered tent were considered to be superior to the BL treatment. The total flavonoid content is increased in the RL and RBL treatments. The antioxidant activity of ABTS was significantly higher in the RBL treatment. This indicates that BL is required for the normal growth, biomass, and accumulation of polysaccharides and phenolic of A. burmannicus, while RBL is enhanced the accumulation of flavonoids and antioxidant activity. This technology is conducive to achieving large-scale sustainable production of high-quality medicinal plant materials. GRAPHICAL ABSTRACT

Design and Simulation of a Circadian Lighting Control System Using Fuzzy Logic Controller for LED Lighting Technology

This paper introduces a fuzzy logic-based circadian lighting control system using flexibility of Light-Emitting Diode (LED) lighting technology to synchronise artificial lighting with circadian (natural) lighting Correlated Colour Temperature (CCT) characteristics. Besides for vision acuity, the Non-Imaging Forming effects of lighting affect human circadian rhythms. Past works in spectrally tuning CCT or Spectral Power Distribution of lighting have used conventional Proportional-Integral-Derivative (PID) control system architecture, where the modelling process of system transfer functions was mathematically complex, especially for nonlinear systems. A methodology of regulating lighting CCT is employed in a 7×5 fuzzy logic rules matrix in a Fuzzy Logic Controller (FLC) system, to closely replicate natural lighting CCT characteristics for indoor lighting. A reference lookup table was devised to store desired CCT values arbitrarily with respect to time mark in a day, which acts as an outdoor circadian stimulus and guides the FLC. The FLC compensates for the lack of CCT in lighting space. Simulation results show acceptable CCT output values conforming to circadian lighting parameters at a time in a day compared to the lookup table targets. Deviation from blackbody curve was within ±0.003 using CCT Duv checking. The system did not produce an overshoot (0.0%) with a steady state (zero error) reached after the fourth iteration. Also, rise time was calculated to be 1 iteration. This approach could be further enhanced to cater for additional custom needs in many built environments. Future works may consider connecting more sensors to capture real-time outdoor CCT values for practical regulation.

Influence of the Advancement in the LED Lighting Technologies on the Optimum Windows-to-Wall Ratio of Jordanians Residential Buildings

Based on recent developments and the predicted future advancement of lighting technologies, researchers are now questioning the extent to which daylight is effective in lowering the overall energy consumption of buildings. As light-emitting diode (LED) luminaires are highly energy efficient, the amount of power consumed for lighting purposes can be reduced, even in situations where the lighting system is at its full power. It has already been demonstrated that LED-lighting technologies can facilitate significant energy savings through minimizing window size (the main source of heat loss in buildings), and there is considerable potential for developing the LEDs’ source efficacy and lighting-product efficiency to ultimately achieve levels of efficacy of approximately 350 lumens per Watt (lm/W). For building designs to be sustainable in the future, it is critical that the windows-to-wall ratio (WWR) is optimized to minimize both heating and cooling loads, as well as the total energy consumed by the building for lighting, according to the efficiency of the LED, while still maintaining a suitable lighting level for occupants. This research examines the influence of the WWR on the total amount of energy consumed by standard buildings in Jordan using various LED luminaires (existing and projected efficiencies). DesignBuilder software was utilized to analyze the effect of LED-technology development on optimizing the WWR for a typical residential structure in Jordan. The research presents beneficial recommendations with respect to optimizing the WWR for primary decision-makers in the design of residential buildings with enhanced energy efficiency, considering the losses and gains associated with solar heat and light to capitalize on solar energy with no adverse impacts by windows size. The outcomes suggest a WWR of 17% could be achieved by typical residential buildings in Jordan that have extremely efficient LED lighting systems (350 lm/W), which is more than 50% less than the existing level of 40% recommended by multiple standards. Additionally, this study highlighted that when the efficiency of LED technologies increases, the energy demand of the building will be reduced because of lower energy usage combined with heat gain resulting from the LED efficiency.

Environmental Impacts of Photoluminescence and Light-Emitting Diode (LED) Lighting Technologies in Horticulture: Case Study on Compact Fluorescent Lamp (CFL) and LED Lights for “Night Break” of Chrysanthemum Cultivation

The environmental impacts of photoluminescence and light-emitting diode (LED) lighting technologies in horticulture are described in this paper. As a case study, the life cycle assessment (LCA) associated with the raw materials, air, water and natural resources of screw-based compact fluorescent lamps (CFLs) and screw-based horticultural LED lamps (abbreviated as H-LED) used for “night break” effect in chrysanthemum cultivation is considered. Instead of the unit of radiant power of lighting sources (lumens) used in human lighting, the photon flux (micromoles per second) of the plant light is used in this study. The results of the study show that the environmental impacts of the H-LED lighting technology are markedly less than the fluorescent lamps. Therefore, the shift to LED lighting technology in horticulture in general, and “night break” chrysanthemum cultivation in particular, brings about tremendous benefits not only for saving energy and improving crop quality, but also for protecting the air/climate, water, soil and natural resources.

Light-Emitting Diode Electronics, Harmonic Issues, and Augmenting Standards [Product Safety Perspectives

The proliferation of light-emitting diode (LED) lighting technology should be a high-priority agenda item in the discourse on lighting energy efficiency and power quality. Considering the future penetration of LED lighting technologies, it is necessary to ensure that LED lamps are performing at the most efficient level without compromising other interrelated issues.

Demand side management perspective on the interaction between a non-ideal grid and residential LED lamps

Lighting industries across the world are witnessing a rapid shift towards energy efficient LED (Light Emitting Diode) lightings. These lighting technologies can be seen asan alternative tool to the DSM (Demand Side Management) in residential, commercial as well as industrial sector. DSM has a strong linkage with the reliability and quality of power supply and any variations in supply conditions may significantly affect DSM strategies. As LED lighting technologies are penetrating the lighting market at a rapid pace, it is important to assess the different impacts of distribution grid conditions on the power quality and energy consumption performance of LEDs. This paper presents an extensive analysis of the consequences of sustained abnormal voltage, supply voltage harmonics, and supply frequency variations on LED lamps and its overall effect on the popular “LED lighting DSM Program” – being adopted worldwide. It was observed that under the variable grid conditions, some lamps’ technologies offer DSM like advantages without being actively engaged in DSM. Several parameters have been evaluated, analyzed and, recommendations have been made for LED-based passive DSM strategies which may encompass the LED manufacturers, the utilities, and the governments.

Using Brainwaves and Eye Tracking to Determine Attention Levels for Auto-Lighting Systems

To prevent car accidents, it should be possible for pedestrians and other drivers to detect oncoming vehicles. Many car accidents are caused because persons are not aware of approaching traffic, and this applies especially to visual awareness. The daytime running light (DRL) and the third braking light (TBL) were developed to significantly increase the visibility of vehicles, and their effectiveness has been verified through numerous studies. Usage of light-emitting diode (LED) lighting technology has also become popular in auto-lighting systems because of its advantages of energy efficiency, long life, and stylish appearance. However, LED lighting technology is very different from conventional incandescent or high-intensity discharge (HID) lighting technology. In this paper, we determine the effectiveness of LEDs as DRLs and TBLs. We measure human attention levels by observing brainwaves and performing eye-tracking experiments that shows the relationship between the theory of attention, brainwaves, and eye tracking. The results obtained show that it is feasible to evaluate automotive exterior lighting using the attention levels of subjects.

Dimming schemes for visible light communication: the state of research

As a new generation green lighting source, the light emitting diode (LED) is rapidly replacing traditional incandescent and fluorescent light sources. Apart from providing energy savings, the use of LED lighting technology creates scope for an innovative optical wireless communication technology known as visible light communication (VLC), which takes advantage of the superior modulation capability of LEDs to transmit data through a wireless channel. VLC is capable of concurrently providing communication as well as illumination. For making commercial implementation of VLC feasible, it is necessary to incorporate it with dimming schemes that will provide energy savings, moods, and increase the aesthetic value of the place using this technology. However, general dimming techniques have an adverse effect on communication since they limit the achievable data rate of a VLC link. This drives the necessity of formulating efficient dimming techniques, which will create a balance between the two most basic functions of VLC: illumination and communication. This paper focuses on dimming mechanisms that can be implemented in VLC systems to save energy and provide precise illumination control. The motivation behind this control mechanism, current challenges in practical implementation, driver circuitry, recent progress, and future prospects are also concisely presented.

LED Lighting for Oil and Gas Facilities

Industrial petrochemical facilities have predominantly used high-intensity discharge light sources and installation practices unchanged for several decades. Today, new light-emitting diode (LED)-based products are being developed, and there appear to be many advantages to this technology; however, caution is advised in its application. This paper examines LED lighting technology, standards, and available products along with design and application considerations. Moreover, presented are case studies of LED luminaire retrofits in existing facilities. This paper discusses the results of the studies as they relate to safety, environment impacts, capital and operating costs, design implications, and installation improvements.

The Effects of Fluorescent versus LED Lighting on Soldier Tasks in Military Tents

It has been shown that lighting can have an effect on human health, cognition, perception and behavior. There is a gap in the literature pertaining to the effects of light emitting diode (LED) technology on humans, and a gap on lighting in military living environments. This is especially important considering that current research and design efforts are attempting to distinguish whether newer LED lighting technologies are the best choice for military use. Building on past work, the current study examines effects of LED and fluorescent lighting technologies on military relevant tasks in an attempt to examine how lighting may alleviate certain military stressors (workload, interpersonal conflict, concerns about living conditions). Results of this study add to the research base comparing LED and fluorescent lighting.

Beacon system based on light-emitting diode sources for runways lighting

New aeronautical ground lighting techniques are becoming increasingly important to ensure the safety and reduce the maintenance costs of the plane’s tracks. Until recently, tracks had embedded lighting systems whose sources were based on incandescent lamps. But incandescent lamps have several disadvantages: high energy consumption and frequent breakdowns that result in high maintenance costs (lamp average life-time is ∼1500 operating hours) and the lamp’s technology has a lack of new lighting functions, such as signal handling and modification. To solve these problems, the industry has developed systems based on light-emitting diode (LED) technology with improved features: (1) LED lighting consumes one tenth the power, (2) it improves preventive maintenance (an LED’s lifetime range is between 25,000 and 100,000 hours), and (3) LED lighting technology can be controlled remotely according to the needs of the track configuration. LEDs have been in use for more than three decades, but only recently, around 2002, have they begun to be used as visual aids, representing the greatest potential change for airport lighting since their inception in the 1920s. Currently, embedded LED systems are not being broadly used due to the specific constraints of the rules and regulations of airports (beacon dimensions, power system technology, etc.). The fundamental requirements applied to embedded lighting systems are to be hosted on a volume where the dimensions are usually critical and also to integrate all the essential components for operation. An embedded architecture that meets the lighting regulations for airport runways is presented. The present work is divided into three main tasks: development of an optical system to optimize lighting according to International Civil Aviation Organization, manufacturing prototype, and model validation.

Light-emitting diodes and their applications in energy-saving lighting

New light-emitting diode technology offers significant promise for reducing energy usage in lighting and display applications. This paper introduces light-emitting diodes, sets their performance in context and predicts how an ultimate reduction of up to 15% of our total electricity consumption could be achieved if light-emitting diodes were to replace existing forms of household, commercial and street lighting. This would be achieved not only through the increased luminous efficacy of light-emitting diode light sources, but also by increasing the power factor of the entire lighting unit and by introducing control systems that take advantage of the long-lasting, fully dimmable nature of light-emitting diodes. However, the high cost of light-emitting-diode-based lighting is the main barrier to widespread consumer uptake. Consequently, this paper outlines routes towards improved performance and lower costs, both for light-emitting diodes and the units they are built into. Because light-emitting diode lighting can offer additional benefits not offered by current technology, such as their application in indoors wireless data transfer, commercial breakthrough will be driven initially by demand for niche applications. In the long term, however, low-cost light-emitting diode lighting technology is likely to play a significant role in energy demand reduction both in the developed and the developing world.

Present Status of White LED Lighting Technologies in Japan

“The light for the 21st century” Japanese national (Akari) project, which is based on the high-efficient white light-emitting diode (LED) lighting technologies using near ultraviolet (UV) LED and phosphor system, has been started at 1998. The near UV white LED system linked with semiconductor technologies on GaN LED and ZnS phosphors for general lighting applications has for the first time been proposed in the project. The outline and purpose of this project are briefly introduced. In particular, we have demonstrated high-efficient nUV LED having external quantum efficiencies more than 43 % around an emission wavelength of 400 nm. Basic illumination properties of the high luminous efficacy (>40 lm/W) and the high general color rendering index (Ra>90) white LED sources are described. The near UV white LED technologies in conjunction with phosphor blends can offer superior color uniformity, high Ra and the excellent light quality for many lighting applications.