From the national "863 Plan" to LED large size Backlight Market

For promoting application of LED in large size backlight assembly on October 2006, the national Ministry of science and technology of large size LCD backlight integrated technology research "," dynamic LED light source system development "low cost included in the" 863 high-tech project ", to guide and promote the development of the large-size backlight including LED chip, package module, large-size backlight, dynamic backlight IC control, dynamic backlight control circuit and optical film matched with the. Only 3 years, LED large-size backlight components in R & D, manufacturing, sales and other aspects have made great progress. Especially since 2009, has entered the stage of marketization.

LED backlight from small to large size TV backlight assembly

2006 years ago, LED is mainly used in the direction of illumination, traffic lights and other lighting requirements of the road is not too high. Because of the low voltage power supply, low power consumption, power supply for portable liquid crystal display products is very easy to solve, from the original use of cold cathode fluorescent lamp (CCFL) to produce the high frequency high voltage, but also reduces the power consumption caused by voltage and frequency conversion. These advantages make LED began in mobile phones, digital cameras, digital cameras and other portable products, and gradually derived such as MP3, MP4 and other portable new products. However, in 2006 LED is still limited to small and medium size (7 inches or less) LCD display. On the technical indicators, the brightness and brightness uniformity requirements are not high; in contrast, color coordinates, color temperature and color gamut and other higher requirements of the technical indicators, there is no requirement.

With the improvement of LED technology, LED product technical index gradually increased, especially the annual comprehensive white light efficiency nearly 10% to 20% of the rate increase, while the market price in almost every year but in 10% to 20% of the rate of decline. Some developed countries or regions, the United States, Japan, the European Union and other general LED lighting and professional lighting included in the new energy, new light source development plan". China will also be integrated white light efficiency 100lm/W as a recent development goal, marking the LED ordinary lighting and professional lighting has come. In October 2006 the State Ministry of science and technology of large size LCD backlight integrated technology research "," dynamic LED light source system development "low cost included in the" 863 high-tech project ", so as to guide and promote the application of LED in large size backlight assembly in TV receiver.

Dili Electronic Co. Ltd 2006 started LED as a light source test in large size TV backlight assembly, because the initial luminous efficiency of LED is not high, so only the production of direct type LED backlight assembly, in order to meet the requirements of brightness, has developed a 19 ", 22", 26 ", 32", 42 "and 47" LED backlight assembly; with the optical efficiency of LED increased, and began to experiment in the side light type LED backlight assembly, side light type 19 "to 32" LED backlight assembly has reached the production level, "42 side light type LED backlight module development success. Since 2008, gradually from the backlight assembly to monitor, TV development. It is understood that a number of major domestic display manufacturers and television manufacturers, will be included in the development of LED backlight product development plan or has begun to put into production. 2009 four quarter and in 2010 the domestic LED backlight module monitors and televisions will be listed, and gradually replace the CCFL backlight products.

From static backlight assembly to dynamic backlight assembly

In order to save energy and improve the contrast of the image, in recent years, the control of brightness or chroma backlight components are also rising. Because of the difficulty of control technology, the control circuit and control software development and manufacturing costs are different, so the backlight module brightness or chroma control is not the same.

Because of the weakness of the liquid crystal, such as light transmission rate is low (only 4% ~ 8%), LED backlight assembly for more than 90% of the light was filtered, the energy loss is larger; and when the dark signal, it is difficult to LCD backlight assembly of light are switched off, resulting in dark signal when the brightness value is still not low, so the static contrast the LCD display is low, generally only about 800:1. In order to save energy and improve the signal contrast, the idea of dynamic backlight came into being. If the entire screen brightness PWM LED backlight control, horizontal zoning control domain brightness PWM LED backlight module, vertical zoning control domain brightness PWM LED backlight module, backlight assembly LED full screen brightness control region PWM, LED backlight R/G/B regional brightness control, LED backlight R/G/B regional brightness and chroma comprehensive control and so on.

With the development of the 863 high-tech project ", so far has 7 patents:" video control LED backlight and control method thereof "(patent)," TFT-LCD LED "backlight module (invention patents)," the use of the LED reflection pits back light module "(utility model patent)," video control LED brightness and chroma of the dynamic backlight module (patent), "LED dynamic backlight control circuit" (patent), "LED dynamic backlight control algorithm" (patent) and "video with low resolution LED display control system dynamic backlight module" (patent), part of the patent at the same time in the international patent application. At the same time, the completion of the 863 high-tech projects, and gradually establish their own independent intellectual property rights. The original only static LCD TV backlight, due to the introduction of the new concept of LED dynamic backlight assembly, after several years of experiments and concluded, according to the dynamic control method is different, it explores a set of suitable for static and dynamic backlight backlight power test signal source.

Through the "863 high-tech items