作者：Blade

Lehman releases 138-inch Micro LED giant screen cinema

MicroLED’s advantages, in contrast, color gamut, resolution, and color rendering have brought a visual feast, making this “black technology” the “heart of the consumer”. From the perspective of application scenarios, MicroLEDs are mostly used in commercial applications.

Lehman releases 138-inch Micro LED giant screen cinema

And now, with the maturity of technology and the gradual decline in cost, Micro LED is completing a gorgeous transformation from commercial to civilian use and has become the first choice for home theater.

Micro LED has gradually become the new favorite of home theater

LEDinside, the Optoelectronics Research Division of TrendForce Consulting, pointed out that the indoor LED display market, including application scenarios such as home theaters, is growing steadily thanks to the market demand for high resolution and high dynamic contrast range (HDR).

In fact, the current large-size display technology is still dominated by LCD, while MiniLED backlight and OLED are competing in the field of high-end TV. But these three technologies are more difficult to break through 100 inches, which also makes it difficult for these three technologies to provide a more shocking and immersive viewing experience in home theater application scenarios.

In addition, even if a product of 100 inches or more is successfully produced, it is very difficult to enter the product due to the large size. In March 2017, a citizen in Wuhan bought a 100-inch Sony 100Z9D. Due to the large size, the TV can only be sent into the consumer’s home by hanging into the home, and the whole process costs 20,000 RMB.

Although the laser technology is suitable for the market above 100 inches, the color of the image of the laser technology is greatly affected by the ambient light, and the display effect is not satisfactory.

Compared with other technologies, Micro LED has an excellent display effect, and the technology has a smaller restriction on product size, and because Micro LED is a modular technology, it is very easy to install in the home. Based on this, Micro LED is focusing on super-sized race tracks and gradually entering the fields of high-end residences, private theaters, high-end clubs, high-end office spaces, and e-sports venues.

At CES2018, Samsung launched the “The Wall” Micro LED TV, which was a rallying call for Micro LED products to enter the home market. Subsequently, LG, Leyard, Skyworth, C-Seed and other companies have released Micro LED household products, opening up the competition of Micro LED technology on the C-end track.

In terms of price, the 118-inch, 4K version of the Smart Wall released by Konka in 2019 is priced at 1.68 million RMB, and the largest 236-inch, 8K version is 8.88 million RMB; while LG’s LG MAGNIT released in September last year has a size of 163 Inches, the price is 306,000 US dollars.

In contrast, the latest private giant screen theater launched by Lehman Optoelectronics shows full sincerity in terms of price.

From B to C, Lehman Optoelectronics announced its entry into the home consumer market

On September 27th, Ledman Optoelectronics held a new Ledman Micro LED private giant screen theater new product launch conference with the theme of “Giant Screen Enjoyment, the future Is coming” simultaneously online and offline. At the meeting, Li Mantie, chairman of Ledman Optoelectronics, announced the official release of the new 4K flagship 138-inch series of “Ledman Micro LED Private Giant Screen Cinema”. At present, the product has been pre-sold in the flagship store of Lehman Optoelectronics on JD.com and Lehman’s official website, with a starting price of 499,999 RMB.

In terms of display technology, the Lehman Micro LED private giant screen theater is based on COB technology, using self-luminous nano-black crystal coating Micro LED can be spliced with ultra-high-definition black jade screens, with a contrast ratio of 1,000,000:1, a color gamut of 125%, and a viewing angle Up to 170°, it has nanosecond response speed and HDR display effect, and the unbounded field of vision brought by the 4K ultra-high-definition high-screen ratio makes watching movies more immersive.

In terms of function, the Lehman Micro LED private giant screen cinema is paired with the self-developed giant screen cinema intelligent system to establish a new interactive form. At the same time, the Lehman Micro LED private giant screen theater can be equipped with panoramic sound to create an immersive sound effect of 7.1.4 Dolby panoramic sound.

In terms of patents, based on 17 years of packaging experience, 16 years of display manufacturing experience, and 7 years of Micro LED research and development experience, Ledman Optoelectronics has accumulated more than 300 domestic patents, including 60 COB related patents, forming a complete independent Intellectual property system.

Osram’s new upgraded white LED illuminates new agricultural development

With the continuous advancement of urbanization, by 2050, two-thirds of the earth’s people will live in urbanized metropolitan areas. Rapid urbanization is causing urban malnutrition. A “city based on indoor planting technology” The farm” revolution is also on the rise. According to a study published in Earth’s Future in 2018, urban agriculture may be the key to feeding the future urban population. It may produce up to 180 million tons of food each year, accounting for approximately global 10% of the production of beans and vegetables.

Osram's new upgraded white LED illuminates new agricultural development

This has also given birth to the development of many new agricultural technologies. With the gradual maturity of environmental control agricultural technology and the obvious decline in the cost of lighting products, the indoor planting mode that uses artificial light to replace sunlight has become the development trend of urban agriculture, boosting the rapid development of urban agriculture. Compared with traditional agricultural planting, plants planted under plant lighting are not affected by the natural environment, can receive more suitable light, nutrition and humidity, and can be produced normally and continuously even under severe conditions or disasters. But this places very high requirements on artificial light sources used in plant lighting systems.

As a leader in lighting technology, Osram is at the forefront of the advancement of plant lighting. Ams Osram’s latest horticultural lighting product OSCONIQ? S 5050 Horti White covers the horticultural white spectrum and promotes more use of non-converted red photons for plants. The lighting provides excellent lamp-level luminous efficiency.

Currently, indoor plant lighting mainly uses a combination of red and blue LEDs, or a combination of red and white LEDs. In fact, the standard white LED used in plant lighting will also emit light in the red wavelength range. However, compared with the direct red LED, the standard white LED emits almost the same amount of red light, and the energy consumption is much higher. many. Therefore, the red light required in plant lighting is often replaced by LEDs that directly emit red light in the lighting system.

Guangdong local standard for classroom lighting in primary and secondary schools

On October 22, the Guangdong Provincial Department of Education and the Guangdong Provincial Market Supervision Administration held a press conference to introduce the prevention and control of myopia in children and adolescents in Guangdong Province, as well as the preparation of the Guangdong Provincial-Local Standard “Technical Specifications for Primary and Secondary School Classroom Lighting.” The reporter learned from the meeting that the standard has been released a few days ago and will be formally implemented on December 1 this year to ensure that the province completes the task of meeting the lighting standards for classrooms in primary and secondary schools in 2023.

Guangdong local standard for classroom lighting in primary and secondary schools

The lighting environment of classrooms in primary and secondary schools is closely related to the health of children and adolescents. The provincial local standard “Technical Specifications for Primary and Secondary School Classroom Lighting” stipulates the technical requirements of fluorescent lamps, LED lamps, classroom lighting quality and energy-saving requirements, installation and maintenance requirements, and acceptance rules for classroom lighting technology in primary and secondary schools. It is suitable for new construction and expansion. , Reconstruction and implementation of lighting transformation of classrooms in primary and secondary schools, including ordinary classrooms, laboratories, reading rooms, dance classrooms, art classrooms, calligraphy classrooms, computer classrooms, memory electronic reading rooms, and other classroom places.

“On the basis of ensuring compliance with national standards, the standard has added a series of innovative indicators.” Gao Xiaodong, director of the electrical department of Guangdong Product Quality Supervision and Inspection Institute, introduced that the provincial local standard “Technical Specifications for Primary and Secondary School Classroom Lighting” clarified the LED lamps Product and installation requirements, add new clauses such as increasing the illuminance at the top of the classroom, adding stroboscopic inspection items, and using products that are beneficial to visual health. Encourage the use of full-spectrum lamps that simulate sunlight to ensure that the classroom light environment continues to meet the standards and provide students with a learning environment conducive to healthy eyesight.

In addition, Guangdong Province has also taken the lead in the country to clarify two levels of indicators for the lighting environment of classrooms. The first level is the minimum requirement of the national standard, and the second level is the higher requirements that are conducive to the health of eyesight and lighting energy saving. It encourages qualified classrooms. Reference use.

Myopia in children and adolescents is caused by many factors, including genetic factors and environmental factors, among which classroom lighting is a major aspect of environmental factors. Zhuo Yehong, deputy director and deputy dean of the Zhongshan Eye Center of Sun Yat-Sen University, said that the important goal of formulating the provincial local standard “Technical Specifications for Classroom Lighting in Primary and Secondary Schools” is to provide teachers and students with a comfortable and healthy light environment to effectively prevent and control myopia in primary and secondary school students.

According to Chen Jiansheng, director of the Sports, Health and Arts Division of the Provincial Department of Education, the Provincial Department of Education will popularize the main content and technical requirements of the local standards to the provincial education administrative departments and all primary and secondary schools in various regions, and promote the implementation of school lighting facilities in place and the lighting environment to gradually meet the standards, To create a light environment conducive to the physical and mental health of teachers and students. He pointed out that it is necessary to promote the standardized construction and transformation of the teaching lighting environment to ensure that 100% of the school classroom lighting meets the national standard requirements by 2023, and to fully complete the task of meeting the lighting standards of the primary and secondary schools in our province.

According to reports, the provincial local standard “Technical Specifications for Classroom Lighting in Primary and Secondary Schools” was initiated by the Provincial Department of Education and under the guidance of the Provincial Market Supervision Administration. The writing units include testing agencies, disease control centers, and eye hospitals. Relevant social opinions, and the compilation process is scientifically standardized.

Scientists can greatly improve the brightness and stability of LED light-emitting nanocrystals

Recently, the U.S. Department of Energy (DOE) Argonne National Laboratory in Lemont, Illinois led the development of an important LED material.

Scientists can greatly improve the brightness and stability of LED light-emitting nanocrystals

The researchers of the reform laboratory team said: “LEDs are highly efficient, emit less heat, and last for a long time.” “Scientists are studying new materials to make LEDs more efficient and longer-lasting, and are used in consumer electronics, medicine, and Security field.”

Researchers and partners from Brookhaven National Laboratory, Los Alamos National Laboratory, and SLAC National Accelerator Laboratory reported that they have prepared stable perovskite nanocrystals for this LED.

“Nature Photonics” published a paper describing the work of the group. “Our research shows that this method allows us to greatly improve the brightness and stability of luminescent nanocrystals,” commented Xuedan Ma, a scientist at the Argonne Nanomaterials Center.

Perovskite nanocrystals are the main candidates for a new type of LED material. But for a long time, it proved to be unstable in testing.

The research team stabilized the nanocrystals in a porous structure called a metal-organic framework (MOF).

Based on the abundant materials on the earth and manufactured at room temperature, these LEDs may one day enable lower-cost TVs and consumer electronics, as well as better gamma-ray imaging equipment, and even for medicine, security scanning, and science. Researched self-powered X-ray detector.

“We solved the stability problem by encapsulating the perovskite material in the MOF structure,” said a scientist at the Argonne Center for Nanomaterials (CNM), Office of the US Department of Energy’s Office of Scientific User Facilities. “Our research shows that this method can help greatly improve the brightness and stability of luminescent nanocrystals.”

“The operating concept of combining perovskite nanocrystals in MOF has been proven in powder form, but this is the first time we have successfully integrated it into the emission layer of an LED.”

Previous attempts to manufacture nanocrystalline LEDs were hindered by the degradation of nanocrystals back to an unwanted volume phase, losing the advantages of nanocrystals and weakening their potential as practical LEDs.

Bulk matter usually consists of billions of atoms. Materials like perovskites are composed of a few to a few thousand atoms in the nanometer stage, so they behave differently.

In their new method, the research team stabilized the nanocrystals by creating nanocrystals in a matrix of MOF, which they described as “like a tennis ball caught by a barbed wire.” They used lead nodes in the framework as metal precursors and halide salts as organic materials.

The halide salt solution contains methyl ammonium bromide, which reacts with the lead in the framework to assemble nanocrystals around the lead core in the matrix.

The matrix keeps the nanocrystals separated, so they do not interact and degrade. This method is based on a solution coating method, which is much cheaper than the widely used vacuum process for manufacturing inorganic LEDs.

MOF stable LEDs can produce bright red, blue, and green light, as well as different shades of each light.

Wani Nie, a scientist at the Center for Integrated Nanotechnology at Los Alamos National Laboratory, said: “In this work, we have demonstrated for the first time that perovskite nanocrystals that are stable in MOF will create bright and stable colors of various colors. LED.” “We can create different colors, improve color purity, and increase photoluminescence quantum yield. This is a measure of the luminous ability of materials.”

The research team used an advanced photon source (APS) for time-resolved X-ray absorption spectroscopy, a technique that allowed them to discover changes in perovskite materials over time. Researchers can track the movement of electric charges through the material and understand important information that occurs when light is emitted.

LED plant lighting is beneficial to greenhouses, but standards need to be improved

A recent study published by Rutgers University in the United States pointed out that although LED lighting can enhance the growth of greenhouse plants, standards still need to be established to determine the best light intensity and color to improve the energy efficiency of horticultural lighting products.

LED plant lighting is beneficial to greenhouses, but standards need to be improved

At present, many lighting companies are selling LED products. The “light formula” usually consists of a combination of wavelength and color ratio, such as a 4:1 red-blue ratio of the spectrum. Plant scientists often use this information to assess the potential effects of lights on plant growth and development. But according to a study to be published in Acta Horticulturae, there is still a lack of standardized procedures for how to calculate these ratios.

AJ Both, a professor in the Department of Environmental Science at Rutgers University and an expert in controlled environmental engineering, said: “The more efficient the auxiliary light source, the less electricity the grower needs to plant crops. We hope to increase indoor crops in a more sustainable and cost-effective way. Production.”

Improving energy efficiency will have a major impact on growers, and information about new plant lighting strategies will help the booming indoor agricultural industry.

According to Both’s previous research, in greenhouses and controlled environments, lamps are used to supplement sunlight and extend the lighting time, helping to produce horticultural crops such as vegetables, flowers, and herbs. The latest developments in energy-saving LED technology to provide a variety of lighting options for the horticulture industry. However, due to the lack of independent information on the performance of the lights, growers cannot easily compare the various lighting technologies and LED options. The study proposes to standardize product labels, which can compare lamps between manufacturers.

Both and colleagues will continue to work on independently evaluating performance indicators, such as power consumption, efficiency, light intensity, and light distribution patterns, and pass this information to commercial growers. His research shows that the latest developments provide opportunities to precisely control the light of LED lights and study the effects on plant growth and development.

This new study recommends the use of a spectroradiometer to measure light output in a specific wavelength range. Researchers report that comparing sunlight with ordinary lamps (including LEDs, high-pressure sodium lamps, incandescent lamps, and fluorescent lamps for plant lighting), the ratio of light is very different. The researchers hope that the work will help develop a standard definition for a specific band (wavelength range).

Over 300 domestic plant lighting industry chain manufacturers

Driven by multiple factors such as the legal commercialization of special cash crops in North America, the epidemic has promoted global awareness of food crises, land shortages, and the rise of plant factories, plant lighting has developed rapidly in recent years. According to the statistics of Frost & Sullivan, the global plant supplement light equipment market has increased from USD 1.76 billion in 2015 to USD 3.79 billion in 2019, with an average annual compound growth rate of 21.1%. Frost & Sullivan predicts that from 2020 to 2024, the compound annual growth rate of the global plant lighting equipment industry market size will remain at 25.5%, and the market size will reach 11.50 billion U.S. dollars in 2024.

Over 300 domestic plant lighting industry chain manufacturers

There are currently four main types of plant lighting on the market: LED lamps, fluorescent lamps, high-pressure sodium lamps, incandescent lamps, and halogen lamps. According to OFweek Industrial Research Institute, by 2021, the global LED plant growth lamp market will account for 60%. It is expected that the penetration rate of LED light sources will further increase in the future, occupying the mainstream of the plant lighting field.

The current global LED plant lighting downstream application market is still mainly concentrated in Japan, the United States, the Netherlands, and other countries. According to the statistics of the LED Research Institute of Gaogong Industry Research, my country’s LED plant lighting exports in 2020 will exceed 500 million US dollars, an increase of 426.3% over the same period last year. According to data from Zhiyan Consulting, the output distribution of my country’s LED plant lighting systems and lamps market in 2019 is 108,300 sets and 409,900 sets, domestic demand is only 14,957 sets, and 59,846 sets, and overseas market demand accounts for seven-eighths.

my country’s LED plant lighting stock market is relatively small, and there is huge room for growth in the future. Compared with the same period in 2018, the market demand for LED plant lighting systems and lamps in my country has grown rapidly in 19 years, with year-on-year growth rates of 21.94% and 22.46% respectively. The Chinese Academy of Agricultural Sciences predicts that according to the current scale of my country’s agricultural industry, the demand for agricultural LED lighting fixtures and their control equipment will reach several billion yuan in the next five years.

On the one hand, in the past ten years, the recreational marijuana industry has gradually begun to legalize. Most countries prohibit the use of cannabis for recreational purposes. In addition to prohibiting the cultivation, sale, and smoking of cannabis, the law also imposes heavy taxes on businesses and individuals that legally grow and sell cannabis. But the Netherlands has always implemented an informal decriminalization policy on cannabis. In 13 years, Uruguay became the first country in the world to legalize the sale and cultivation of cannabis; on October 18, Canada followed closely. Currently, recreational marijuana is legalized in countries such as Canada, Georgia, and Uruguay, as well as some states in the United States. The vast majority of hemp needs to be grown indoors, and these increased demands will drive the growth of plant factories, thereby driving the demand for the plant lighting market.

On the other hand, all countries and regions around the world are promoting vertical farms. Vertical farms with huge growth space in the future will continue to drive the growth of the plant lighting market. According to statistics from Frost & Sullivan, it is estimated that in 2024, the global market size of plant supplementary lighting equipment applied to the plant factory sector will reach 1.47 billion U.S. dollars, and the compound annual growth rate from 20 to 24 will reach 44.2%.

Because of the low cost of traditional plant lights, they are still used in plant lighting. However, as artificial light source technology matures, LED light sources with more advantages gradually replace traditional light sources and gradually become the main light source for plant lighting. LED light source plant lighting is more efficient and energy-saving. The use density of lamps for agricultural lighting is extremely high compared to general lighting. San’an Zhongke’s research shows that plants with high light demand consume up to 500-1000W of electric power per square meter of planting area, which places stringent requirements on the electrical-to-optical conversion efficiency of plant lights. At present, the electro-optical conversion efficiency of LED plant lamps is more than 20 times that of incandescent lamps, 3 times that of fluorescent lamps, and nearly twice that of high-pressure sodium lamps.

In terms of driving power, LED plant lighting driving power has more stringent requirements than other LED driving power in terms of conversion efficiency, temperature control, precise dimming, and warranty life. In terms of conversion efficiency, the higher the efficiency of the LED plant lighting drive power supply, the lower the power loss and the loss efficiency in the form of heat dissipation. For terminal planting, it can not only save electricity expenses but also control the temperature in the plant factory, so that excessive temperature will not affect the optimal growth of plants. In terms of precise dimming, the LED plant lighting drive power supply provides functions such as adjustable spectrum and intelligent programming to realize that the plant lighting system finally outputs the light required by the planted plants according to the spectral requirements of different plants. In terms of warranty life, plant lighting needs a longer warranty life of the power supply, so there are higher requirements for the reliability and quality of the driving power supply.

Domestic companies are rapidly deploying plant lighting business. In 2020, there will be more than 300 companies engaged in plant lighting in my country. Upstream chip manufacturers such as San’an Optoelectronics, HC Semitek, and Qianzhao Optoelectronics have deployed the plant lighting LED light source market segment, and midstream packaging companies such as National Star Optoelectronics, Hongli Zhihui, Everlight Electronics, and other leading companies have focused on plants. Lighting technology.

2021-2022 Global LED Lighting Market Outlook

With the gradual popularization of vaccines in various countries, the market economy has begun to recover. Since 1Q21, the LED general lighting market demand has obviously recovered. TrendForce forecasts that the global LED lighting market will reach 38.199 billion US dollars in 2021, with an annual growth rate of 9.5%.

2021-2022 Global LED Lighting Market Outlook

The main growth momentum of the general lighting market comes from four factors:

1. With the gradual popularization of vaccines in various countries, the market economy has gradually recovered, especially the rapid recovery of commercial, outdoor, and engineering lighting.

Second, the price of LED lighting products increased: With the pressure of rising raw material costs, lighting brand manufacturers continued to increase product prices by 3-15%.

3. With the support of energy-saving and emission-reduction policies in various countries around the world, in order to achieve the goal of “carbon neutrality”, LED energy-saving renovation projects have been gradually launched, and the penetration rate of LED lighting has continued to increase. According to TrendForce’s analysis, the LED lighting market penetration rate will increase to 57% in 2021.

4. Under the epidemic situation, LED lighting manufacturers are accelerating their deployment towards digital intelligent dimming and regulation of lamps. The future lighting industry will also pay more attention to the systemization of connected lighting products and the added value brought by human health lighting.

Qingdao Metro basically achieves full coverage of LED lighting

After the country made the major strategic decision of “carbon peak by 2030 and carbon neutral by 2060”, relevant departments have successively issued guidelines on accelerating the development of new energy storage, and a series of notices on further improving the time-of-use electricity price mechanism. The policy document promotes the implementation of the “dual carbon” goal in the power sector, and the transportation sector requires “accelerating the promotion of green and low-carbon development, and the carbon dioxide emissions in the transportation sector reach the peak as soon as possible.” For many years, Qingdao Metro has been committed to exploring how to better fulfill its social responsibility for green development, and play an exemplary and leading role in green and low-carbon development.

Qingdao Metro basically achieves full coverage of LED lighting

Taking the development history of lighting lamps as an example, from high-energy-consuming incandescent lamps to low-power LED lamps, behind the realization of energy saving is strong support for technological innovation. Qingdao Metro has always placed technological innovation in a prominent position, actively carried out energy-saving “four new” technology application research in the whole process of design, construction, and operation, and continuously promoted equipment energy-saving upgrades, and strived to reduce operating energy consumption from the source. Through technological innovation, Qingdao Metro has saved more than 10 million kilowatt-hours of electricity per year and reduced carbon dioxide emissions by 10,000 tons.

Develop clean energy and obtain clean energy from nature. Qingdao Metro has vacant roofs and elevated station roofs in some sections of the site, and installed photovoltaic power generation with an installed capacity of 3MWp and an annual power generation of 3 million kWh; photovoltaic street lights are used in the Anshun depot to achieve “zero” power consumption for road lighting; parking in Lingshanwei uses air-source heat pumps to absorb heat in the air to provide heat for the office area. In addition, Qingdao Metro has completed the photovoltaic design of the idle roofs of 4 depots, with a construction area of 181,000 square meters and a total installed capacity of 16MWp. It is expected to generate 18 million kWh of electricity annually. The development of clean energy is an effective way to achieve sustainable development. In the future, Qingdao Metro will continue to cultivate in the field of clean energy represented by solar energy, wind energy, and hydrogen energy, paving the way for the application of clean energy in the rail transit industry.

Pay attention to the utilization of waste energy and turn waste electricity, waste heat, and wastewater into treasure. Metro trains generate electricity when braking, but the generated electricity is too much to be fully utilized, and a large part of it will be wasted in the form of heat energy. Qingdao Metro has installed nearly 40 regenerative braking energy absorption devices to collect the wasted electricity for supply. Vehicles and station equipment are reused, saving more than 9 million kilowatt-hours of electricity annually. The operation of subway equipment will generate a lot of heat, which requires ventilation and air-conditioning for cooling. Qingdao Metro adopts heat pump heat recovery technology on Line 13 to collect waste heat and provide heat for the public areas of the station and office buildings, which not only saves cooling energy consumption but also reduces heating energy consumption. A sewage treatment system is set up at the site to treat production and domestic wastewater to form reclaimed water for sanitary cleaning and green irrigation, so as to realize the recycling of water resources. Waste energy utilization is an effective means to reduce energy waste. In the future, Qingdao Metro will conduct applied research in the field of composite energy storage represented by flywheel energy storage to promote the rapid iterative upgrade of energy storage equipment in the rail transit industry.

Improve the energy efficiency level to make the equipment more efficient and lower energy consumption. The 112 stations on the Qingdao Metro line network basically achieve full coverage of LED lighting. The early stage of the site has also completed the energy-saving transformation of 4450 metal halide lamps. Only the lighting of the site section is retrofitted, which can save up to 1.1 million kilowatt-hours of electricity; the line network use frequency conversion escalators and no one automatically turns to idle speed operation, reducing no-load energy consumption; 36 sets of integral, direct expansion evaporative and condensing cold water systems are used for lines 1, 2, and 13, and some of them use magnetic levitation coolers to replace the traditional screw chiller not only improves the heat exchange efficiency and saves operating energy consumption, but also saves the area of the cooling tower and avoids the problem of noise disturbance. The use of high-energy-efficiency equipment can significantly improve energy efficiency. In the future, Qingdao Metro will conduct technical research in the field of traction energy-saving represented by permanent magnet technology to help train energy efficiency in the rail transit industry.

How to reduce light pollution caused by outdoor LED lighting?

During the New Year holidays, houses and businesses are decorated with holiday lights, many of which are equipped with LEDs. These decorations are usually only lit for a period of time on holiday nights, but those permanent lighting fixtures that are always on throughout the year are different.

How to reduce light pollution caused by outdoor LED lighting?

Anyone who has flown over cities at night knows that all these lights are fascinating, but unfortunately, they make the sky glow and can have serious adverse effects, especially on wildlife and vegetation.

As the lighting industry gradually reduces the use of traditional light sources (such as high-pressure sodium or metal halides for outdoor lighting), people are paying more and more attention to how to minimize the light pollution caused by outdoor LED devices.

GFZ German Earth Science Research Center recently released the results of a study on urban street lighting in Tucson, Arizona, in-depth analysis of how well-designed LED lamps can minimize light pollution. Tucson is the city that uses LED lighting the most. Almost all street lights have been upgraded and have wireless communication and dimming functions. The study was conducted for 10 days in March and April 2019, and images of the Tucson area were acquired at night through the Suomi National Polar Orbiting Partnership (NPP) satellite of the United States. At some nights, about 14,000 of the total 19,500 street lights are set to full brightness, other times they are set to 30% bright.

The research team concluded that about 20% of the nighttime light in Tucson is from street lights, and the rest is generated by architectural signs and curtain walls, shop windows, sports fields, etc. If these conclusions apply to other cities, it indicates that LED lighting design may be able to solve the problem of light pollution.

In order to minimize light pollution or stray light, the most important tool used by luminaire designers is the “BUG” rating system. “BUG” stands for backlight, upward light and glare. The BUG rating system is jointly developed by the Lighting Engineering Association (IES) and the International Dark Sky Association (IDA), which can provide a unified method to evaluate the amount of stray light generated by outdoor lighting.

Stray light in the outdoor environment is harmful and unhelpful. It not only causes the sky to glow, but also causes unnecessary energy consumption. Examples of stray light are intrusive light (that is, light that enters from an undesired position, such as light from a street lamp into a nearby window), upward light that helps the sky glow, and glare (light that is flush with the line of sight). Too much light can cause discomfort or visual impairment).

According to the lumen output measured in each of the three areas shown in Figure 2, the BUG rating can be obtained.

As the name suggests, backlight refers to the light emitted behind the lighting equipment. The backlight area can be further divided into four sub-areas, and the corresponding emission angles range from 0 degrees (that is, the light points downward to the ground) to 90 degrees (most of the light is parallel to the ground and points to the outside). Similarly, the glare area is also divided into four sub-areas, and the emission angle increases from low glare to high glare. The upward illumination area includes only two sub-areas, one area contains light mainly directed upwards, and the other area contains light mainly directed outside.

The look-up table of IES TM-15-11 (Outdoor Lighting Classification System) quotes the measured lumens of each of the above-mentioned partitions, and the value assigned to each parameter is in the range of 0~5, and the BUG rating is based on this. For example, the BUG level B0 U0 G0 is assigned to the lighting device that emits downward light; the BUG level of B2 U0 G2 is assigned to the lighting device that emits most of the illuminating light forward and backward, but not upward. Please note that the BUG level is only a factor in determining whether a lighting device is suitable for a particular lighting application. Generally, the lower the BUG level, the lower the possibility of light pollution.

Outdoor waterproof LED power supply solution

According to the ENELTEC global supply chain database report, the LED lighting market demand has fully recovered since the first quarter, and the second quarter has maintained the prosperity of the previous quarter. The price is hovering in the high-end position. The medium and high power will also begin to increase rapidly in the third quarter.

Outdoor waterproof LED power supply solution

With the accelerated construction of smart cities, outdoor LED lighting products are gradually replacing traditional lighting products and becoming mainstream applications in public transportation infrastructure such as highways, bridges, tunnels, and airports. Youshang pointed out that, as an indispensable part of LED lighting products, LED drive power has rapidly grown in scale driven by the market. Compared with traditional lighting products, LED lighting products to have the characteristics of high luminous efficiency, stability and durability, dimming, and easy control. However, because LEDs work outdoors for a long time and the living environment is relatively harsh, the requirements for their power sources are becoming more and more stringent.

The LED power solution launched this time uses ON Semiconductor’s LLC driver NCP13992, synchronous rectification driver chip MPS6922, and PFC driver NCL2801, which meets the IP67 waterproof rating and can provide stable performance even in harsh environments. And this driver is the industry’s first LLC controller with current control mode. This controller has a built-in 600V gate driver, which simplifies the layout and reduces the number of external components.