LED industrial chain: substrate- epitaxial wafer-chip-packaging- application. In China, in 2008, the value of LED is up to 70 billion RMB; In 2009, the value of LED chip is up to 2.3 billion RMB, which has grown 25% than 2008, the packaging production value is up to 20.4 billion RMB, the value of LED Illumination is up to 60 billion RMB; In 2009, the value of LED is 80 billion RMB, it is growing quickly so that the annual production value of 2010 is more than 100 billion RMB. By the end of 2009, china packaging production ranks the first and holds 70% in the world.
The primal problem of restricting the development of LED is the temperature, the photoelectric conversion efficiency of high-power LED of more than 1W is 15%, and the remaining 85% will be converted to the heat energy. The power density on the chip of1mm-2.5mmis more than 300W/mm2. The product structure of China LED industry in 2009 includes 52% applications, 11% chip packaging and 37% chips. The product application of LED industry has also contributed to a large number of relevant industries, especially the lamps and the control power supply and other industries.
Comparison of LED light emitting diode and other light source
Currently, there are many light sources of lower energy consumption, long life, high lighting effect, such as three band fluorescent lamp, compact fluorescent lamp, metal halide lamp, sodium lamp, cold-cathode tube and LED, which has meet the needs of the indoor and outdoor illumination energy conservation. Among many high efficiency light sources, LED is the fastest growing light source with the widest application area, especially the application in the outdoor landscape lighting and indoor artistic lighting, and is also applied in the indoor functional lighting. Bellowing table indicates several comparisons in the lighting engineering.
Common basic technical parameters of the light source
Because LED is the solid light source with small size, quick response, assembly module, driven by DC power supply, it has brought the great convenience for the lamps manufacture. According to demands, we can produce all kinds of functional lighting lamps such as art lamps.
During the downstream production of LED lamp, there are several technical questions needs to solve, including the heat dissipation technology, power drive and control technique and optical technique, lamps manufacture technology and engineering application technology. It is very important to improve the luminary efficiency. Except the conventional method, we can also use the paster process of the polymer reflective material to improve about 10% luminaire efficiency. LED light source is applied in the building engineering in the early stage. Early application includes LED signal lamp in the distribution box and cabinet, the footlight, emergency export lamp, instrumental displays and so on. Today, the lamps varieties of the engineering application have already been comprehensive. Because the inherent characteristics of LED light source, the lamps is applicable in frequent vibration occasion, mobile lighting equipment, explosion proof lighting equipment, medical lighting equipment, emergency lighting lamps, nightscape lighting and so on. In terms of the indoor and outdoor functional lighting, because the lighting effect and the cost performance of the current LED lamp is still not ideal, there is a certain restriction in the application, from the development tendency of LED light source, it is just the matter of time.