New LED light source system with uniform illumination for line-scan CCD imaging systems

A system with uniform light reflection in the inner surface within a horizontal 2/3 cylindrical structure for line-scan CCD of the print testing was designed. The design was based on diffuse reflection uniformity of the integrating sphere and requirement of the strip uniform illumination region. This system was called dome light. White light LED array light sources were used for uniform illumi- nation. The LEDs were filtrated to composite array light source based on coefficient of variation of a single LED. The standard white board and SG color checkers were used in the line-scan CCD imaging experiments under the dome light and ordinary illumination light source. The average color difference （AE） of SG color checkers in CIELAB space was 2. 091 under the dome light and 2. 286 under ordinary illumination light source respectively. Experimental results indicate that the dome light can satisfy illumination uniformity and color rendering consistency for line-scan CCD and provide a standard light source for uniform calibration of different cameras.

Effects of different LEDs light spectrum on the growth,leaf anatomy,and chloroplast ultrastructure of potato plantlets in vitro and minituber production after transplanting in the greenhouse

Light spectrum plays an important role in regulating the growth and development of in vitro cultured potato(Solanum tuberosum L.) plantlets. The status of potato plantlets at the end of in vitro stage influences the minituber production after transplanting. With 100 μmol m^-2s^-1 total photosynthetic photon flux density(PPFD), a light spectrum study of 100% red light emitting diodes(LEDs) light spectrum(RR), 100% blue LEDs light spectrum(BB), 65% red+35% blue LEDs light spectrum(RB), and 45% red+35% blue+20% green LEDs light spectrum(RBG) providing illumination at the in vitro cultured stage of potato plantlets for 4 weeks using fluorescent lamp as control(CK) was performed to investigate the effects of LEDs light spectrum on the growth, leaf anatomy, and chloroplast ultrastructure of potato plantlets in vitro as well as the minituber yield after 2 months transplanting in the greenhouse. Compared to CK, RB and RBG promoted the growth of potato plantlets in vitro with increased stem diameter, plantlet fresh weight, plantlet dry weight, and health index. Furthermore, BB induced the greatest stem diameter as well as the highest health index in potato plantlets in vitro. Root activity, soluble protein, and free amino acid were also significantly enhanced by BB, whereas carbohydrates were improved by RR. In addition, thickness of leaf, palisade parenchyma and spongy parenchyma was significantly increased by BB and RBG. Chloroplasts under BB and RBG showed well-developed grana thylakoid and stroma thylakoid. Unexpectedly, distinct upper epidermis with greatest thickness was induced and palisade parenchyma and spongy parenchyma were arranged neatly in RR. After transplanting in the greenhouse for 2 months, potato plantlets in vitro from BB, RB, and RBG produced high percentage of large size tuber. BB improved fresh and dry weights of the biggest tuber but decreased tuber number per plantlet. In addition, RBG increased tuber number as well as tuber fresh and dry weight slightly. Our results suggested monochromatic blue LEDs as well as combined red, blue or/and green LEDs light spectrum were superior to fluorescent lamp spectrum in micro-propagation of potato plantlets. Therefore, the application of RBG was suitable;BB and RB could be used as alternatives.

Transcriptome analysis reveals effects of red and blue lightemitting diodes(LEDs)on the growth,chlorophyll fluorescence and endogenous plant hormones of potato(Solanum tuberosum L.)plantlets cultured in vitro

Red and blue light illumination has been reported to significantly affect plantlet growth.Potato is an important food and feed crop in the world and potato plantlet cultured in vitro plays an important role in potato production.However,few studies have documented the effects of red and blue light on the growth of potato plantlets revealed at the transcriptome level.The objective of this study was to determine the growth and physiological responses of potato plantlets cultured in vitro under monochromatic red(RR),monochromatic blue(BB)as well as combined red and blue(RB)LEDs using the RNA-Seq technique.In total,3150 and 814 differentially expressed genes(DEGs)were detected in potato plantlets under RR and BB,respectively,compared to RB(used as control).Compared to the control,the DEGs enriched in"photosynthesis"and"photosynthesis-antenna proteins"metabolic pathways were up-regulated and down-regulated by BB and RR,respectively,which might be responsible for the increases and decreases of maximum quantum yield(F_(v)/F_(m)),photochemical quantum yield(φ_(PSII)),photochemical quenching(q_(P))and electron transfer rate(ETR)in BB and RR,respectively.Potato plantlets exhibited dwarfed stems and extended leaves under BB,whereas elongated stems and small leaves were induced under RR.These dramatically altered plantlet phenotypes were associated with variable levels of endogenous plant hormones gibberellin(GAs),indoleacetic acid(IAA)and cytokinins(CKs),as assessed in stems and leaves of potato plantlets.In addition,monochromatic red and blue LEDs trigged the opposite expression profiles of DEGs identified in the"plant hormone signal transduction"metabolic pathway,which were closely related to the endogenous plant hormone levels in potato plantlets.Our results provide insights into the responses of potato plantlets cultured in vitro to red and blue LEDs at the transcriptomic level and may contribute to improvements in the micro-propagation of potato plantlets cultured in vitro from the light spectrum aspect.

Design and Analysis of Traffic Information Transmission System Based on Visible Light Communication

Visible Light Communication( VLC) based on LED is a new wireless communication technology with high response rate and good modulation characteristics in the wavelengths of 380- 780 nm. Compared with conventional methods,the waveband of VLC is harmless to human and safe to communication because of no magnetism radiation. An audio information transmission system using LED traffic lights is presented based on VLC technology. The system is consisted of transmitting terminal,receiving terminal and communication channel. Some experiments were made under real communication environment. The experimental results showed that the traffic information transmission system works steadily with good communication quality and achieves the purpose of transmitting audio information through LED traffic lights,with a data transfer rate up to 250 kbps over a distance of 5 meters.

LED光照对生物絮团模式下凡纳滨对虾肌肉营养成分的影响

LED光源具有节能环保、光电转化效率高等优点,可满足工厂化养殖对绿色高效、智能化发展的需求。为探究LED养殖灯对生物絮团模式下凡纳滨对虾(Litopenaeus vannamei)肌肉品质的影响,以凡纳滨对虾幼体(平均体长5.23±0.61 cm,平均体质量1.52±0.47 g)为材料,设置2个处理组:LED光照组(L组)和自然光照组(N组),进行为期8周的养殖试验。L组光照参数为蓝绿光混合(绿光545 nm、蓝光450 nm),光照周期15 L∶9 D,光照度2000 lx;N组光照参数为自然光谱,光照周期为12L∶12D,光照度400~1000 lx。结果显示,两组对虾肌肉常规营养成分(水分、粗蛋白、粗脂肪、灰分)均无显著性差异(P>0.05)。两组对虾肌肉中均检测到18种氨基酸,L组对虾肌肉苏氨酸(Thr)、酪氨酸(Tyr)、精氨酸(Arg)、甘氨酸(Gly)、∑EAA/∑NEAA显著高于N组(P<0.05),而必需氨基酸(EAA)、半必需氨基酸(HEAA)、呈味氨基酸(DAA)均无显著性差异(P>0.05)。两组对虾肌肉中均检测到37种脂肪酸,L组对虾肌肉中月桂酸(C12:0)、DHA、EPA+DHA含量显著高于N组(P<0.05),C21:0、C20:3n-3、C22:5n-6含量显著低于N组(P<0.05)。研究表明,在生物絮团养殖模式下,补充特定参数的LED养殖灯能够改善凡纳滨对虾肌肉营养品质。

Effects of stimulating frequency of NIR LEDs light irradiation on forehead as quantified by EEG measurements

Near-infrared(NIR)light has been shown to produce a range of physiological effects in hunans,however,there is still no agreement on whether and how a single parameter,like the flicker frequency of NIR light,affects the brain.An 810 nm NIR LED was used as the stimulator.Fifty subjects participated in this experiment.Forty subjects were randomly divided into four groups.Each group underwent a 30-minute NIR LED radiation with four different frequencies(i.e.,0 Hz,5 Hz,10 Hz and 20 Hz,respectively)on the forehead.The remaining 10 subjects formed the control group,in which they underwent a 30-minute rest period without light radiation.EEG signals of all subjects during each test were recorded.Gravity frequency(GF),relative energy change,and sample entropy were analyzed.The experimental groups had larger GF values compared to the control group.Higher stimulation frequency would cause larger growth of GF(F=14.75,P<0.001).The amplitude of alpha waves relative energy increased,while theta waves decreased remarkably in the experimental groups(p<0.02),and the extent of increase/decrease was larger at higher stimulation frequency,compared to that of the control.Sample entropy of electrodes in the frontal areas were much larger than those in other brain areas in the experimental groups(p<0.001).Larger frequency of the NIR LED light would cause more distinct brain activities in the stimulated areas.It indicates that NIR LED light may have a positive effect on modulating brain activity.These results may help improve the design of photobiomodulation treatments in the future.

Real-time Audio &Video Transmission System Based on Visible Light Communication

With the increasing popularity of solid sate lighting devices, Visible Light Communication (VLC) is globally recognized as an advanced and promising technology to realize short-range, high speed as well as large capacity wireless data transmission. In this paper, we propose a prototype of real-time audio and video broadcast system using inexpensive commercially available light emitting diode (LED) lamps. Experimental results show that real-time high quality audio and video with the maximum distance of 3 m can be achieved through proper layout of LED sources and improvement of concentration effects. Lighting model within room environment is designed and simulated which indicates close relationship between layout of light sources and distribution of illuminance.

Optical wireless network in home area based on white LED lights

A new optical wireless network based on white LED lights in home area is proposed. It is a duplex channel communication system utilizing signal emitters of white LED lights in the downlink and infrared devices in the uplink. Strategies for the system construction are given. Performance for users＇ mobile access of different kinds of optical concentrators is investigated. Indoor channel band-width is analyzed considering white LED light distribution, wall reflection, and receivers field of view （FOV）. Various modulation methods are discussed. A demo point-to-point system for surfing the net is constructed using a new line code of 4B6B which is developed to stabilize the optical output, and a peak data rate of 1 Mbps is achieved. This system is built into the lighting infrastructure, therefore decreasing the cost and offering a solution for wireless access in places which are sensitive to radio frequency like hospitals.

Standards for Tunnel and Road LED Lighting Application Technologies

The paper summarizes the research on the development of standards for tunnels and roads LED lighiing application in Shanghai. analyzes the existing problems on LED road lamps and lighting design, introduces the experiments and testing results, and summarizes current problems of LED street lighting, proposing that LED lighting energy conservation should he ＂systematic energy saving＂ throughout the full life cycle based on the integration of products and applications.

New High Efficiency LED Lighting Solution

As the quality of power LED improves and the cost of power LED reduces, semiconductor lighting will replace incandescent and fluorescent lighting gradually, causing another revolution on the lighting history. And its driving solution has been greatly accelerated. Based on the white power LED I-V characteristics and the application ambiance, proposed is a new LED lighting solution, suiting indoor and outdoor illumination. According to the test results, the design is optimized, and the electrical efficiency is 95% and the output current deviation is 13.0%.

Effects of Low Temperature and Poor Light Environments under LED Lighting on Quality Change of Pepper Seedlings during Storage

Storage and transportation of vegetable commercial seedlings becomes an important link along with the continuous expansion of planting areas of facility vegetables and vegetable seedling culture industry. In this study,pepper variety‘Nongda 24' was as the experimental material,and changes in the morphological and physiological indicators of plug seedlings in different low temperature( 6 and 11℃) and poor light environments were studied to find suitable storage environmental conditions. The results showed that pepper seedlings could be stored and transported for 14 days when storage temperature was 11℃ and light conditions such as light intensity and photoperiod were 30 μmol/( m^2·s)and 12 h/d by using a fluorescent lamp with R∶ B ratio of 1. 9,and 15 μmol/( m^2·s) and 24 h/d by using LED with R∶ B ratio of 1. 3,respectively. Moreover,the quality of pepper seedlings could be protected effectively. Compared to the fluorescent lamp,LED with high luminous efficiency and low energy consumption was suitable for the storage or long-distance transportation of pepper seedlings in low temperature and poor light environments.

Treatment of Peripheral Neuropathy: Combination Therapy Using LED Light, Extracorporeal Shockwave Therapy, Platelet Rich Plasma, and an Oral Dietary Supplement

Objectives: Peripheral neuropathy (PN) is a significant contributor to disability in the elderly. It is also one of the most prevalent complications of type 2 diabetes, prediabetes and metabolic syndrome. PN is commonly associated with pain, numbness, tingling, burning, and cramping in the feet and legs. Current treatment options are limited to controlling pain, seizures and use of antidepressant medications. These treatments have undesirable side effects and don’t stop PN progression. Here we utilized a combination of individual-specific modalities to improve local circulation and relieve PN symptoms. Methods: We conducted an open-label, multicenter pilot trial with 34 subjects (19 males and 15 females ranging from 40 - 85 years of age). All of the participants were diagnosed with peripheral neuropathy and had bilateral symptoms in their feet, and many reported the same symptoms (pain, numbness, tingling, burning, and cramping) in their lower legs. The duration of symptoms ranged from four months to over six years. On Day 0, subjects were given a 90-day supply of the oral supplement with dosing instructions and a LED light therapy device. They also received three platelet-rich plasma (PRP) injections in their lower extremities. Subjects also received an extracorporeal shockwave therapy (ESWT) treatment for each foot and subsequently twice per week for the first six weeks, then once weekly for the duration of the study. Subjects filled out the Brief Pain Index (BPI) at weekly intervals. On Day 90, subjects completed the Patient Global Impression of Change (PGIC) survey. Results: There were significant responses to pain, as evidenced by BPI scores at weeks 8, 9, 10 and 11 (p = 0.02, 0.01, 0.02, and 0.003, respectively). Analysis of the final day PGIC survey showed a favorable outcome for 73% of participants (p = 0.003), with the majority reporting Very Much Improved. Conclusions: By utilizing a multi-modality treatment protocol that includes PRP, LED light therapy, ESWT and an oral dietary supplement, we observed significant reductions in BPI scores. Quality of life and their overall impression of change (PGIC) were significantly improved, and there were no significant side effects.

解析一款LED电脑灯——High End Systems SolaWash Pro 2000

通过对SolaWash Pro 2000的检测,分析该LED灯具的构成、功能及其性能和特点。

Controlled LED Lighting for Horticulture: A Review

As energy gradually becomes a more valuable commodity, the desire for reduced energy losses strengthens. Lighting is a critical field on this matter, as it accounts for a large percentage of the global electricity consumption and modern lighting systems are greatly more efficient than incandescent, discharge, and fluorescent lights. Previous research has proven that plants do not require the entire visible spectrum but react only to specific wavelengths, making it possible to control their growth and yield via artificial lighting. The flexibility of control of Light Emitting Diode (LED) lights allows for the combination of great energy losses reduction and controlled plant growth, achieving the improvement of two major parameters in a single action. This review paper summarizes the current research on the effect different light wavelengths have on specific plant species and discusses the applications of LED lighting for horticulture, yield storage, and disease protection.

Accelerated Luminous Depreciation Testing for LED Lighting Products

With the application of energy-saving, environmental and durable LED lighting products, the reliability testing has become a pivot point for the large scale industrialization and popularization. The paper briefly introduces two methods to be respectively applied in the accelerated depreciatinn lesting for the luminous flex of LED lighting products and the life of outdoor LED-driving power, which can sharply shorten the time for lifetime lest. providing references for the LED lighting products＇ reliability evaluation.

Analysis of Current Research and Future Development Trends of Applying Solar Energy in Street Lighting

In the context of promoting green energy transition and addressing climate change globally,solar energy,as a clean and renewable energy source,has gradually become a hot topic for research.Solar streetlight systems realize energy self-sufficiency and environment-friendly lighting by integrating photovoltaic power generation technology and efficient LED lighting technology.By comprehensively analyzing the current status of the application of solar streetlights at home and abroad,this paper discusses its technical advantages,market penetration,and challenges in its development.In terms of technical characteristics,this paper focuses on analyzing the key technologies such as energy conversion efficiency and intelligent control systems of solar streetlights.

基于LED光源DLP前照灯系统策略研究与验证

本文以LED辅助光源的DLP前照灯系统为研究对象,开发一种应对多种场景需求的DLP前照灯系统策略及控制逻辑。采用整车及系统台架实测验证,试验结果表明,LED辅助光源的DLP前照灯系统能够很好实现人车防眩目,坡度及转弯、高速公路等工况自动照明,提高夜间行车驾驶安全。

LED智能灯光控制系统设计与实现

随着LED照明技术的快速发展,社会需求也在持续变化,即从单纯的照明需求向智能化需求转变。特别是在移动互联网时代背景下,LED智能灯光控制成为主流趋势,其依托LED照明的基础功能,在其中融入移动互联、智能控制等前沿技术,实现了LED照明的智能化、实用化和新颖化。据此,基于LED智能灯光控制系统,围绕移动互联的独特应用背景,探讨系统的技术应用及设计方法。介绍了LED控制技术以及移动互联技术等相关内容,提出LED智能控制系统技术应用原则,最终形成LED智能灯光控制系统设计方案,以设计出一种稳定、实力、可靠的系统,满足日益多元化的应用需求。

基于安卓平台的LED智能蓝牙灯控系统设计

智能蓝牙灯控系统的硬件部分采用ATmega48单片机作为MCU控制核心,以ATK-HC05作为蓝牙传输模块,设计通信模块接口电路。软件部分基于安卓平台的App作为控制终端,采用RFCOMM串行线性仿真协议,确保数据传输的完整性,设计整个无线通信程序,实现各种光模式的开关控制、亮度控制和模式转换。经测试该方案切实可行,并具有操作方便、成本低廉的优势。

可调LED光源系统设计及其对菠菜生长的影响

为提供设施农业装备运用的人工光源,进行了发光二极管(LED)光源系统的硬件及软件设计,并通过以荧光灯为对照对6种柔性组合的LED光源,进行了菠菜生长试验。研究发现该系统具有光质、光强、光周期及占空比柔性可调,可以作为设施补光及光生物学研究的理想光系统。在该光系统下的菠菜生长试验发现,菠菜在红蓝黄(RBY)光处理下叶柄长、叶面积、叶柄粗及根长都显著大于其他处理,生长较其他处理健壮,且RBY光处理菠菜光合色素质量分数显著高于其他处理,表明在红蓝复合光的基础上添加黄光有利于光合色素的合成,并显著地促进菠菜的生长,同时也表明该LED光源系统对开展植物补光应用具有一定的现实意义和使用价值。