作者：Blade

The low FPY (First Pass Yield) slows down the development of LED lighting industry

With the ban of incandescent lamps with power consumption larger than and equal to 100W issued by the National Development and Reform Commission on October 1st of 2012, the LED lighting industry received strong supports from related government policies. It is clear that the entire lighting industry is transforming from traditional lighting to LED lighting.

 

The low FPY (First Pass Yield) slows down the development of LED lighting industry

 

During this period of time (when incandescent lamps have been gradually replaced by new lighting sources), LED lamps are not completely resisted by ordinary consumers. They just felt hesitate to accept. Currently, LED lighting products are still in an immature stage: unclear product identification, lacking of unified standard, products with different quality. Recently, the Guangdong Provincial Bureau of Quality and Technical Supervision spot checked some LED samples from different LED Panel Light manufacturers. The truth is the FPY of these samples is too low.

 

In this spot checking, among totally 23 samples (more than 100 for each sample) from 21 LED manufactures, 17 samples did not pass the test. The pass rate was less than 30%. The low FPY (First Pass Yield) slows down the development of LED lighting industry.

 

Experts gave advices about LED lighting products on the market:

 

1)       Inspect the packaging at first: trademarks and certification marks are necessary, like 3C certification, CE certification, RoHS certification, etc.. Besides, some basic technical parameters also cannot be ignored: the rated voltage, voltage range, color temperature, precautions, safety instructions, application environment.

 

2)       Price comparison: As a result of the expensive production cost, the average selling price of LED lamps is usually around 45 yuan. (Products from large brands will more expensive, like Phillips, OSRAM, etc.) Besides, the glaze surface is also very important, without any glue mark, without any protruded screws. And the color of screws should be identified with the color of the surface.

 

3)       Buyers should carefully examine the color change after the lamp has been switched on. If the light changed from yellow to white or from white to blue-white during the short time after lamps being switched on, there must be something wrong the drivers or light sources. Also for small-power MR16 spotlights, using inappropriate transformers may cause flickers. High-frequency electronic transformers are more suitable for this kind of products.

The entry point of LED lighting market

Since October 1st of 2012, China will gradually ban the import and sale of incandescent lights according to the power consumption. The phase-out process of incandescent lighting products has entered the implementation phase. New lighting source, especially the LED lighting industry will continue to obtain great supports from the government. LED lighting market has bright prospects and huge potentials.

 

Since October 1st of 2012, China will gradually ban the import and sale of incandescent lights according to the power consumption.

 

LED lighting applications are speeding up their penetration into the market. For now, LED lighting industry is on the threshold of a dramatic boom.

 

The hottest LED lighting applications in the mainland is LED road lamps and LED Panel Light. With the support policy from the Ministry of Science and Technology, LED road lamps were promoting at an amazing speed. Both purchasers and suppliers showed their enthusiasm in this area. Presently, there are estimated one million pieces LED street lights will be installed in 21 pilot cities within ten years. And another plan of two million pieces LED street lights within 50 pilot cities is ongoing. This is a characteristic of China. This is a generation speed of China. It is too fast that this market may probably be destroyed by foams at the end.

 

In the LED T8 application area, according to the previous market plans, there are some mature commercialized products that had been promoted in the LED lighting market. It is believed that LED T8 application market is the first mature LED lighting market. The most commonly used LED T8 tube applications are parking lot lighting, shopping center lighting and advertising backlight. The selling prices in these area have already reach the critical point (150).

 

High-quality products have sophisticated technologies in optics, cooling designs and power suppliers. However, there are still a large number of low-quality LED products in the market, which is the biggest challenge for the commercialization of LED products. With the launch of standards from the Energy Star and EU, the above problems may greatly be improved.

 

Theoretically, lamp cover is the begging of lamps’ development. However, for a very long time, LED manufacturers could not solve the multi-specification problem and led to the embarrassing situation that the development of LED lamp cover is far behind that of the other compartments. Although the cost of LED lighting products has dropped sharply, there is still no major improvement in the global LED lighting market. Which LED technology can finish the commercialization and become the new darling of the market after LED T8 Tubes?

Brief analysis for LED lighting applications market trends

The bright development prospects of LED lighting applications make people feel more confident in the LED lighting market. Nowadays, the world is under the threat of energy shortage. Governments all over the world launched environmental protection policies and increase support in the LED industry. With the vigorous development of LED lighting technology, LED lighting applications has gradually transferred from street lighting, outdoor landscape lighting to indoor residential lighting and commercial lighting.

 

The bright development prospects of LED lighting applications make people feel more confident in the LED lighting market.

 

Currently, LED Panel Light has been deeply used in the residential lighting area. Although domestic LED market is still dominated by LED street lights (for industrial purpose) and LED flood lights (for commercial purpose), LED panels and LED downlights with dimming and RGB functions started to attract the attention of ordinary buyers and merchants. The over-expensive production cost is the biggest obstacle that hindered the promotion of LED productions in the residential lighting area. Thus after 20-year development, LED still can hardly be accepted by the household lighting market. Using sapphire as chip substrates, using gold as conducting material, there is no doubt that LEDs are also known as “noble lamps”.

 

It is estimated that by 2015, the market penetration of LED lamps will reach up to 16.8%. Under the stimulus of governments support policies, the penetration rate of LED household lighting applications and street lighting applications will sharply increased. LED bulbs and LED tubes are stable growing every year in Japan’s lighting market. The main force is from the earthquake happened in March 2011, in Japan. The Japanese Governments started to realized the important of energy saving and environmental protection. In the mean time, a large number of new LED suppliers entered this area and speeded up their production and development. Take 500×500 LED chips for example, compared with 2010, the overall supply raised by 41% in 2011. On the contrary, the demand grew only 10%, which led to the oversupply of 500×500 LED chips in 2011. 2011 is a challenging year for LED manufacturers. Due to the slow growth of we LED TV sales and the improvement of luminous efficiency of LED chips, since 2010, the TV backlight industry faced with demand reversal problem. But overall, the demand for LED in the LCD backlight applications is also slightly increased, pulse the improvement of PC and LCD display applications, which compensated for the gradually declined demand in the TV market.

The working principle of LED wall washer

With the development of high power LED lighting technology, high power LED lighting applications have been widely used. High power LED wall washer is just one of the most favorable applications. In this article, we will introduce to you some basic knowledge of LED wall washer and their working principles.

 

With the development of high power LED lighting technology, high power LED lighting applications have been widely used.

 

LED wall washing lights are also called linear LED flood lights, as a result of the long strip shape. This type of lights is usually used in the architectural and decorating lighting area. They have very similar functions with LED flood lights, outlining the contours of large buildings or walls, and also very similar technical parameters. The only difference is the shape of the spot. LED flood lights have circular spot, while the stripe structure of LED Panel Light wall washing lights make the cooling work become easier.

 

Currently used LED wall washer basically use 1W high-powered LED tubes (each LED tube has a PMMA lens with a high luminous efficiency, the main function of which is secondary distribution of the light emitted by LED tubes). These tubes are single-line arranged. Most LED wall washing lights use same heat radiator with LED tubes. However, there are some manufacturers will apply separated cooling devices for these them. There are two general beam options: narrow (about 20 degrees, with the farthest projection distance of 15-20 meters), medium (50 degrees) and wide (around 120 degrees). The normal power specifications are 8W, 12W, 24W, 36W. The normal length specifications are 300mm, 500mm, 600mm, 1000mm. Buyers can choose different length and power density according to their specific engineering applications.

 

High-powered LED wall washing applications have two control modes: internal control and external control. Internal control mode needs no external controllers and embedded multiple changing modes (six tops), while external control mode needs external controllers to change the color, but can have hundreds of changing modes. Thus LED wall washing applications on the current market is usually external controlled.

 

LED wall washer realized the automatic control through the built-in microchip, achieving a series of lighting effects: gradual transition, color flashing, random flashing, alternating dynamic effects. All these functions can also be controlled by DMX consoles. The main application areas: the monomer architecture, historical buildings, indoor/outdoor lighting, green landscape lighting, billboard lighting, medical/cultural/specialized facilities lighting, bar and other entertainment atmosphere lighting.

Comparisons between LED grow lamps and HPS

Scientists have already developed a series of plant-gardening lighting technologies. LED grow lamp is one of these technologies, which is usually compared with traditional HPS (high-pressure sodium lights). LED grow lights combined red rays and blue rays. Normally, they will be settled on the ground, or places near plants. What are the differences between LED grow lighting products and HPS? What advantages that LED grow lights have?

 

Scientists have already developed a series of plant-gardening lighting technologies.

 

1)       Plants under the LED-light will grow faster. Various data shows that LED grow lamp is a superior technology, which make plants grow better and faster. The Department of Horticultural Science of the University of Minnesota has recently published a related study report of plant lighting. In this study, LED grow lights and LED Panel Light HPS have been comprehensively compared in different conditions. They compared plants (after 7 weeks) from two different local plant bases using these two kinds of lamp relatively and found out that, the average growing speed of LED-used plants will be higher than that of HPS-used plants. The difference is noticeable.

 

2)       LED costs less. Indeed, the initial production cost of LED lamps is usually higher than that of HPS lighting sources. But if take the operation cost into account, high-quality LED grow lamps can save more money in this part. With the same output luminous flux, high-quality LED grow lights consume only 1/8 of energy that HPS needed, and more durable than HPS. Usually, grow lights should work in 24 hours. In the long term view, the initial cost of LED light sources can be ignored.

 

3)       LED grow lamps are lighter. Traditional grow lighting sources are relatively heavy, since HID, MH and HPS need ballasts to maintain a normal working condition; reflectors to concentrate light towards plant pools; other assisted tools or equipments. Gardening lamps usually need to hang on certain places, like the close top of plants. The weight is a must-be-considered factor. Some high-quality LED grow lights have embedded ventilators, negating the need of air-cooled reflector or pipelines.

 

LED grow lamps make things much easier, generating sufficient red and blue rays that needed by plants, intelligent self-control system and manual adjusting system, saving more maintenance and replacement cost for users.

The future of LED lighting technology

Here in this article, we will continue the interview of Professor Holland Yake from the University of Illinois, who is an expert of laser and light emitting diode (LED Panel Light ). The topic of today’s interview is the future of LED lighting technology.

 

Here in this article, we will continue the interview of Professor Holland Yake from the University of Illinois

 

Is there anything we can do to improve the LED lighting technology?

 

There are a lot of things that we can do to make them more competent to be the best and brightest lighting source in the world. Currently, we are looking for better wafers, committing crystal chemical researches, etc.. I made an alloy in GE. Then I made other semiconductor alloys, they are getting better. They can emit red-orange light, and also yellow light. Some other people who were doing similar works tried to use other types of alloys, which are able to send out blue rays. But when they tried to convert these blue rays into green, they met with big problems. No one presently can solve this problem very well and obtain yellow rays.

 

After these years development, has LED been the mainstream lighting source?

Basically, LED is beginning to take over the lighting market, from special lighting to ordinary lighting. For now, the whole world is using this technology, in various forms and various colors.

 

Is it possible for us to see the continuous growth of LED lighting technology?

You can treat them as a kind of lighting source, but also can use them as laser, just like in the field of surgery and photosensitizing. This is the biggest feature of LED, since incandescent bulbs cannot do these staffs. You can use LED to make a lot of things, both in the medical area, the instrumental area the automobile area. All lights used on vehicles can be replaced by LED lights. As a matter of fact, LED lamps are more advanced in automobile applications due to their small sized and flexibility in forms and designs. LED headlights and taillights are more durable compared with traditional high-pressure sodium lamps. This is not the end of the story. To be honest, LED is in her infancy. It seems that LED has already stepped into her adolescence, but trust me, she needs more time to grow up. The only thing we can do now is just wait.

History of LED lighting technology

As early as 1962, about 50 years ago, Nick Holonyak together with his team in GE developed the first Light Emitting Diode (LED). Today, LED lighting technology can be seen everywhere in the world – from bridges to vehicle headlights, from keychain to flashlight. As the 4th generation lighting source, LED is even supposed as the lighting source that brighter than the sunlight. But the initial research and development works were full filled with uncertainty and competitive. At that moment, LED lighting technology was just a result from another pioneering technology – laser. However, in the followed days, LED Panel Light has been in the constant evolution and now has been one of the major lighting applications in many areas. What the history of LED? About this question, reporters interviewed Professor Holland Yake from the University of Illinois:

 

As early as 1962, about 50 years ago, Nick Holonyak together with his team in GE developed the first Light Emitting Diode (LED).

 

What the initial reaction that LED received from the market?

When I noticed that I am working on the way of LED development, I have already defeated the entire world by applying my alloy technology in the field of laser. One editor of the “Reader’s Digest” called me in February 1963 and pointed out to me that LED lighting technology will one day cover the entire spectrum and become the most suitable lighting source for white-rays. I believed his words. But in my opinion, this will take more than 50 years.

 

About the Laser?

It has been recognized for a very long time that light has no coherence. Otherwise, they cannot be captured by our eyes. Since human eyes can only sense incoherence light. In 1962, Lincoln Laboratories of MIT was still under the leadership of Robert Rediker. They invented a kind of diode that can self-emit multiple rays and used it to send out IR signals. When they published a copy of relevant report in July, we predicted that this new device will make the coherence light be possible.

 

How big is the first LED?

Very small. Of course, if you want, you can make it much bigger. Actually, people are now doing this job. You know, in the area of semiconductor application, semiconductors are always the final winner and swept the electronic products.

 

What was the original LED looks like?

LED you see today is on a relatively cheap platform, which is just a formality. In fact, LED can be made in various forms, various colors, various geometries.

Future development: low carbon applications of OLED display technology

Working principles of OLED is sandwiching an organic light-emitting layer between two electrodes. The collision of positive electrons and negative electrons will generate photons. OLED screens have very strong anti-interference capacity, showing clear images even in the strong sunlight. OLED is free from lead, mercury, cadmium and other harmful materials. In addition, the energy consumption of OLED is much smaller than LCD and plasma display devices and has been globally recognized as the most green low-carbon equipment in the display industry.

 

Future development: low carbon applications of OLED display technology

 

OLED display technology has the followed advantages:

 

1)       Thinner, clearer, brighter;

The unique production process gave OLED a lot advantages compared with other traditional display devices, thinner, clearer, brighter, lighter weight and lower manufacturing costs. The panel structure and divers of OLED screens are all under accurate calculations and special designs. Technicians can maintain the thickness of OLED screens within a relatively thin level and meanwhile make them high-brightness, high-resolution and high contrast. OLED is self-luminous without any backlight. OLED display technology consumed much less power than LCD, but the optical output is three times than that of LCDs.

 

2)       Ring, ribbon, and other curve surfaces heterosexual installations.

OLED display system uses a unique modular structure, which can be customized as any size or shape (ribbon, ring, erected, spherical, etc.), any ratio of height and width, seamless stitching. Spaces and places where display applications were totally incompetent, nowadays have been installed all kinds of large-scaled OLED screens. OLED display technology provides more creativity for designers in space design.

 

As a new generation display technology, OLED has high-brightness, consume less power, can work under low input voltage, have longer service life, have high impact resistance and stable performance. OLED screens have been widely used in the advertising and commercial area. Presently, many domestic manufacturers started the research and development works for OLED display technology, including the TV News giant CECV. In the near further, mature OLED and LED Panel Light products will finish the process of commercialization and be put on the market. OLED display industry and application market is enjoying a rapid development. Thank to the highly sophisticated stability and product performance, OLED screens with high quality and high IP level have already been used in the field of intelligent traffic security system. It is believed that OLED display applications have broader prospects in the security area.

Intelligent applications: LED traffic guidance screens in the intelligent transportation

The production and application of LED traffic guidance screens involved multiple technologies, including: semiconductor, optoelectronic technologies, integrated circuit, image processing and transmission, computer network communication, and manufacturing of electronic products. LED screens of different types and different performances will have huge differences in the aspect of material constitution, production process and control. Even products with same types and same performances but from different manufacturers, still have differences due to the different technologies used by these companies. LED traffic guidance screens can accurately transmit the real-time traffic information to drivers. They have following characteristics:

 Intelligent applications: LED traffic guidance screens in the intelligent transportation

 

 

1)       High brightness, reasonable visual angles:

Road traffic-induced information is mainly oriented to vehicles traveling on the road. They have less demand on visual angles. ±30o is sufficient. LED screens outside traffic guidance rooms should work in 24 hours. In the condition of direct sunlight, the display contents should be visible. It is required that LED traffic guidance screens should have a certain level of brightness. The visual distance under normal circumstances should be around 200m.

 

2)       Red, green yellow will be three major display colors

The release of traffic information is mainly oriented to dynamic vehicles. Within the visual distance, dynamic vehicles stay for a very short time. Complex multi-grayscale graphics and animation content should be replaced by simple graphic logos or texts. Red, green and yellow are three prime colors that used in traffic signs, red represents stop, green represents suggestion, and yellow represents warning.

 

3)       The brightness of screens can be automatically adjusted

LED traffic guidance screens normally worked on 24 hours in any environmental conditions. Makers should make sure that these their products are clearly visible during the sunny daytime with the maximum brightness, and also avoid the glare in rainy days and nights. Thus it requests that these screens should be capable of automatic adjusting. In normal conditions, the automatic adjusting range should not less than 8.

 

4)       Remote control, intelligent detection

The installation passion of LED traffic guidance screens is distributed over a large area. Remote intelligent control systems are necessary. The widely distribution of LED screens makes the daily testing and maintenance work become more difficult. Remote control system can intelligently detect faults and do some simple adjustments. It is also a very important part of the intelligent transportation system.

New area of LED display applications: the Road Security

In 2011, China outdoor LED electronic display advertising market reached 1.215 billion yuan, an increase of 35.5% over the previous year. According to statistics, the size of the advertising market is expected to reach 1.55 billion yuan at the end of 2012, a growth of 27.6%. In recent years, with the government support in green lighting projects, the LED lighting industry enjoyed a vigorous development and formed a complete LED industrial chain system. LED application area gradually expanded, especially in the field of traffic safety, LED display applications became more and more popular as assist of intelligent transportation systems.

 

In 2011, China outdoor LED electronic display advertising market reached 1.215 billion yuan

 

LED screen is a good security monitor, the market development directly impact the direction of the security industry. Outdoor LED Panel Light screens have unparalleled advantages in intelligent transportation systems, which is also an important development direction of LED display applications. With the unprecedented prosperity of LED technology, LED display products are widely used in commercial advertising, life broadcast, traffic induce, stage interpretation, etc.. So far, LED screens presented some obvious characteristics:

 

1)       Large-scale production;

Chinese LED display industry are not only dominated in the mainland market, but also occupied in the market of other countries and regions, gradually forming stable exports. Product quality and reliability have been significantly improved. Manufacturers of LED display applications from the mainland had very good performances in large projects and in the global competitions.

 

2)       Technological innovation has played a positive role in leading and promoting the development of the industry.

China’s LED display technology kept path with the international development for a very long time. New products have been promoted continuously in the past two years, active innovations, improved developing capacities. Key technologies and mainstream products have more mature developments.

 

3)       The standardization and intensification of the LED display industry.

LED display industry associations actively promoted the products and technological exchanges and carried out standardization works. Standardization led to the upgrading of the level of industrialization. The industrial layout is in the process of intensification. There are a large number of large-scaled LED enterprises concentrated in Shenzhen. The most significant feature of China’s LED display application industry in recent years is the obvious increase of the number of large-scaled LED enterprises, and the sharply reduction mid-sized LED companies. In addition, the number of small-sized LED companies was also increased.