About the mechanism of light-emitting LED light source

Now, with the LED industry supply with mature, low barriers to entry, a large influx of small businesses, resulting in excess of the LED bulbs, and because its production capacity utilization rate is low, certainly compete in the market giant Philips brand (Philips), Osram (Osram) and GE, these manufacturers through vertical integration or strategic alliance layout, the main active occupation of LED lighting market. Whether exploited or through gross margin much larger rivals, small factories and thus escape the huge market pressure.
China has rich resources of non-ferrous metals, gallium, indium-rich, the world's total reserves of 70% -80%, which makes the development of semiconductor lighting industry in China has the advantage of resources. By 2010, the Chinese LED industry output will exceed 150 billion yuan. As early as 2002, Japan spent ¥ 5 billion to implement white light illumination, the program's budget of 60 billion yen.
With the rapid growth of LED penetration, along with the price war will come in 2010, because unlike the traditional lamp and LED downlight source separate from the sales model, in this pressure, some companies can not take into account quality and price competitiveness, may will fall to the merger or be doomed.
May 7, 2010 -12, Henan Province, lighting, lighting experts and entrepreneurs learn to organize his party visited Japan Japanese lighting situation, found that Japan's current situation is not satisfactory LED lighting.
In recent years, in light of the most interesting event is the rise of the semiconductor lighting. The mid-1990s, Japan's Nichia Corporation Nakamura, who through unremitting efforts, broke through the manufacture of blue light-emitting diode (LED) of the key technologies, and thus developed a fluorescent material to cover the blue LED technology produces white light source .
led the LightEmittingDiode (light emitting diode) acronym. New solid-state light-emitting diode is a cold light source, LED's most notable feature is the long life, high photoelectric conversion efficiency, good seismic performance, ease of use in the lighting system more widely. Under the same illumination, LED tube and power consumption than incandescent and fluorescent lifetime have clear advantages.
White light of various methods of development, and development of next-generation phosphors, LED luminous efficiency has led to a substantial increase in current industrial products from 45lm / w up to 100lm / w (2009, Cree's cold white light efficiency when at 350mA over 100lm / W, while the warm white light is more than 75lm / W), the level of research 160lm / w, the highest level of expectations of the target 200lm / w or more. Life of 40,000 to 80,000 hours.

Thermal simulation to simplify the development of LED light source

Any form of electrical lighting products have a negative product: heat. Incandescent lighting to fluorescent lighting from generation to generation engineers in R & D will minimize heat or heat from the light source separation methods or equipment. However, LED spotlight, currently to continuously improve the quality and increasing form, bringing a new and different challenges.
The development will reduce the heat LED light output, causing the color change, while reducing component life. Said thermal management is by far, the most critical of the LED system design aspects. From an engineer's point of view, this means learning across the structure and tools commonly used in electronic design, electronic design to be familiar with the structure and outside the scope of the process. Fortunately, we already have thermal design solutions, validation and testing in the heat challenges, design engineers can help simplify the road.
Developing a new light system, must verify the most basic product concept, the structural and aesthetic ideas and thermal properties of the actual needs can be unified.
The key success of the LED system design activities, equipment, heat is effectively carried over from its move to the PN environment. PCB and solder the LED housings are involved in the heat flow path. Design engineer must determine the transfer of heat in the shell and shields demonstrated efficiency. Series of physical samples manufactured and tested to verify this is expensive and requires more time, therefore, has the early stages of design engineers in the design of commonly used software-based approach.
More popular approach is to use computational fluid dynamics (CFD = Computational Fluid Dynamics) analysis to simulate the planned virtual devices. For early design concepts, this approach to be flexible than building a lot of physical samples, and just as effective. That the characteristics of a good virtual model, the physical samples can be clear on the basis of what works and what does not. All along, CFD simulation by some of the fluid with a high-level data and analysis of background people to operate, it requires the implementation of personnel in the analysis of complex CFD modeling tools.

The latest CFD technology development will be brought to the structural engineer's desktop, greatly simplifying and speeding up the analysis. The new process, that is synchronized CFD, the preparation and execution of simulation steps to automate most of the work required. Seamless integration with common MCAD in the environment, such as Pro / ENGINEER ®, making the structural engineers can design a new light source to create a virtual simulation model, and detect heat dissipation.
Design verification of the bottom line, whether the product is a new source or modify an existing design, should be a detailed understanding of the thermal performance of LED bulb. If the development of new LED lamps in place of existing equipment, then learn more about the thermal performance is also very important, because the original installation of thermal performance and lighting facilities is the key.
Thermal data from LED suppliers should get the hands, although in the current industry standard in the absence of such information, product specifications in the printing, the information provided is usually not comprehensive enough. For example, the thermal performance data are usually provided, but it may not include the operating temperature range, the actual end-user systems in which the temperature of the work areas. However, design engineers must rely on LED manufacturer's data or simple models to evaluate the implementation of light, or in-house testing, or start early light design.

Six LED application market analysis

Application: the main application market is the LED display, full-color display robust growth.
Early start of China's LED display market, the market appeared a group of highly powerful LED display manufacturer. Currently LED display has been widely applied to the station, bank, securities and hospitals. Demand on the LED, LED display LED indicators in second place behind, the overall LED sales accounted for 23.1%. As for the LED display on the brightness and lifetime requirements higher than the LED lights, LED lights above the average price, which led to the display with LED market reached 3.24 billion yuan, topped the list as more than light The main LED application market. With unique advantages, LED full color display widely used in sports stadiums, municipal square, concerts, stations, airports and other places.
Application 2: small size backlight market slowdown, the large size will become the new focus.
LED has long been used in mobile phone-based small-size LED light backlight market, mobile phone production growth led backlight market's rapid development. In particular, the emergence of color screen mobile phones in 2003 is to promote the rapid development of white LED market. But with the steady growth phase into the production of mobile phones and mobile phone technology to enhance the lead for LED LCD panel backlight to reduce the number, making the LED backlighting in mobile phones in the amount of slowdown in 2005, with LED backlight number over 1.2 billion, the future years, the growth rate will remain in the single digits. The average number of growth slowdown coupled with falling prices, leading to the small size backlight market sluggish, while large-size backlight Although manufacturers market darling, but in 2006 still can not scale. In the above two factors, the backlight market in 2006, a 1% negative growth. 2005 backlight market size of over 1.5 billion.
Application 3: Large market potential for car headlights, but the short term the market is difficult to start.
2005 China Automotive LED application market was 0.29 billion, of which automobile headlights market 0.21 billion. From the LED application market, the automotive market is still in its infancy, the market is small.
LED lights as the car driven by low power consumption, long life and the corresponding speed and quickness. Statistics show that, in the car traveling at 100 kilometers per hour, the vehicle is equipped with LED brake lights are not equipped with LED brake lights than the vehicle braking distance will be reduced by 7 feet. Currently, LED has been gradually applied to the third brake light on the car. Although the LED is still faced with the unit low wattage lumens and related policy constraints, the taillights and headlights into the car market will take some time, but with the decline in the cost-performance ratio and improved luminous efficiency, the LED will gradually realize the ultimate from the vehicle's interior, rear to the front of the transfer, and ultimately occupy the entire automotive lamp market. With the huge capacity car, LED lamp market faces enormous development potential.
Application 4: Interior lighting market has started to enter the market, traffic lights steady growth.
Interior LED lighting market is another emerging market. By current control, LED can achieve hundreds or even thousands of color change. At this stage, the era of personalized attention, LED color LED decorative lights will help diversify the market's development. LED has begun to make small decorative lamps, decorative wall applications in hotels, living room. Interior lighting market in 2005 reached 158 million.
After years of replacement work, the nation's major cities from the traditional traffic lights replaced with LED traffic lights have been drawing to a close. LED traffic lights for many years the market has experienced rapid growth after the 2005 market reached 15.2 billion yuan. But with the completion of the replacement work, LED spotlight lights will no longer maintain market growth is expected to LED traffic lights in 2006 to achieve only 5.8% of market growth to reach 1.61 billion yuan.
Application of five: the rapid development of landscape lighting market, the market growth rate peaked in 2007.
Landscape lighting market, mainly in streets, squares and other public places, decorative lighting, the main driving force mainly from the government. By the 2008 Beijing Olympic Games and 2010 Shanghai World Expo impact of Beijing, Shanghai and other organizations to accelerate the pace of landscape lighting, the LED low power consumption, electricity consumption in the huge landscape lighting market with strong market competitiveness. Currently, LED has been increasingly applied to the landscape lighting market. 2005 Chinese landscape lighting market size of more than $ 700 million in the two main activities, led landscape lighting market will reach 72% in 2007, the high growth rates. In addition, the Olympics and World Expo will be the main role is far longer on their own landscape lighting market to drive growth, more importantly, their role models. In order to meet the Olympic Games and World Expo, Beijing, Qingdao and Shanghai, will build a number of LED landscape lighting, decorative street in these projects will also serve as a model. Other cities see the LED lighting in the landscape will reduce the outstanding performance of the use of LED landscape lighting concerns, accelerate the use of LED landscape lighting applications. LED will fast from one city to the secondary and tertiary urban expansion.
Application of Six: the general lighting market road is long, long way to go.
For into the general lighting market, power white light LED in addition to face, such as low efficiency, poor heat dissipation, high cost and other issues, will face the optical, electronic control and other institutions and the integration of LED lighting products, and develop common standards . Solve these problems requires a long period of time, CCID Consulting forecasts that LED in 2010 can not enter the general lighting market.
As the hotel, Business Center, high-end commercial office buildings and other commercial establishments relative to the price sensitivity is low. At the same time these high-end places more emphasis on highlighting the quality and dignity of the position, for the new products have a greater degree of interest. These are LED lighting to reduce the barriers to entry. LED lighting is expected to be the first to enter the commercial market, and gradually extended to the civilian market.

Identification of the merits of LED lamps

LED energy saving lamp energy-saving effect is obvious because of its long life, no stroboscopic effect, no noise, light, soft and wide operating voltage range of features and increasingly welcomed by consumers. But the current energy-saving lamps on the market led many, the quality varies greatly. How to light an array of energy-saving lamps in the shop to buy their satisfaction with the products? Through the "four to see" the merits of energy-saving lamps can be identified, described below.
A look at packaging and labels
National mandatory product LED tube manufacturers in the packaging marked the following: the rated voltage range, rated power, rated frequency. In general, a trademark of printing high-quality products of good quality, legible, easy to fall off, with a soft damp cloth, signs legible, indelible, have the manufacturer's trademark and related certification mark. Shoddy products, poor quality printing, fonts, fuzzy, easy to erase, no manufacturer's trademarks and related certification mark.
Second, look at the appearance of LED lamps
The real energy-saving LED lights, with three color tubes, tube white, hand cover, even more white, while more than two tubes together to compare the shape and size lamp consistency better than large-scale products, quality is guaranteed. The shell can not have cracks, loose, the seal should not have been prized in the installation, demolition process, lamp should not be loose, head tilt phenomenon.
Third, look at working temperature
LED energy saving lights in normal operation, the temperature should be low. Otherwise, LED energy saving lamp life is very short. Meanwhile, energy-saving lamp is lit, a quick flashing or very harsh fluctuations, indicating that the energy-saving lamps are of questionable quality.
Four to see start-up performance
LED energy saving lamp start has two characteristics: First, the higher the temperature the easier starts; Second, turn off lights, not flash. It is also worth mentioning that opened a lot of LED lamps is very dark, which is detrimental to lamp life, LED energy-saving lamps should be equipped with its internal power supply circuit and PCB board

LED lighting capture the market of the three stages of strategic development

Light green, small size, high reliability and other features increasingly prominent. The higher the tariffs, the use of longer places of business applications, LED lights quickly became the new darling of the market. As the use of LED lighting, LED market in several stages.
LED lamps to replace accepted
This phase refers to the LED lamps in the early stages of development, mainly reflecting its high light efficiency (energy consumption), and long life. Because the price was high, so at this stage mainly for business according to the market. Customers have a process to accept, is to use the habits and appearance of the transition and acceptance. Consistent with the traditional light sources in use case, LED lighting reflects the saving, longevity and other characteristics of the market makes it relatively easy to accept the high price. Especially in commercial applications. The quality of various manufacturers to fight the price advantage.
LED lamps utility model
In the last phase, based on the market for LED lighting products have a certain amount of recognition and acceptance. Green LED lamps, small size, high reliability and other features increasingly prominent. Thus developed a series of completely different from the traditional light source applications of the product will be popular. Lighting industry will be a more open space for development. Light is no longer only have a lighting effect, making it more appropriate for people of varied work life bit by bit. The company is designed to fight the application advantage.
LED lighting intelligent control
From home to office, from the road to the tunnel, from cars to walking, from the auxiliary lighting to the main lighting, with intelligent control of LED lighting systems will bring a higher level of human services. LED lighting products industry will also be made to design products to provide total solution process. With things such as the development of new technologies, LED as the semiconductor industry, high-speed trains will also catch this tour, to play its high controllability characteristics.
Initially dominated by monochromatic LED, although the power is small, the price is high, but its high reliability, controlled, small volume, so the market is the rise of the first electronic device indicator. Market for LED lighting products have a certain recognition and acceptance. With the gradual development of LED lighting, auxiliary lighting in the lighting project and other public places, LED light gradually replace some of the traditional products.

LED light source and the history of the concept

LED (Light Emitting Diode), also LED ceiling light as light-emitting diodes, it is the use of solid semiconductor chip as luminescent materials, when the ends with a positive voltage, the semiconductor carrier in place complex, release excess energy and cause photon emission to produce light .
Application of the principles of semiconductor PN junction made of dimmable LED lights came in the early 1960s, first appeared in 1964, red light-emitting diodes, and then a yellow LED. Until 1994, blue, green LED was developed. 1996, developed a white LED.

LED light principle

LEDs are PN junction silicon, electrodes and optical system. From the light - the chip area of 10.2mil (1mil = 0.0254 square millimeters), a large number of current international chip LED spotlight, the chip area of 40mil.
The luminescence process involves three parts: the forward bias carrier injection, recombination radiation and energy transfer. Tiny semiconductor chip is encapsulated in epoxy resin material in a clean, when the electronic through the chip, with the negatively charged electrons to positively charged holes move the domain and with the compound, the disappearance of both electrons and holes generate photons. Between the electron and hole energy (band gap) increases, resulting in the higher energy photons. Photon energy in turn corresponds with the color of light, visible light spectrum, the blue light, violet light energy to carry most, orange light, red light energy to carry the least. Because different materials have different band gap, which can emit different colors of light.