The application of LED in backlight module has the advantage of power saving

LED is applied to backlight module as light source to replace the traditional cold cathode fluorescent tube (CCFL). It not only has the advantages of light and thin power saving, small volume, long service life, low voltage and fast startup, but also has the concept of environmental protection. For notebook computers, depending on the processor and size, the power consumption of LCD panel accounts for about one third of the whole machine. Due to the low power consumption of LED, the service time of Nb using LED backlight can be extended by more than 1.5 hours. The thickness of the light guide plate with LED can be reduced from 2mm to 0.6mm (13.3-inch product), the thickness of the screen can be reduced, and the weight of the whole machine will also be reduced. At present, each CCFL contains about 2mg of mercury. Using LED as light source can reduce the use of mercury. If RGB three colors are mixed into white light, it can provide better color saturation, and the color of TV picture will be more bright. The LED can achieve regional dynamic control and turn off when some areas are black, so as to improve the contrast between light and dark, and save power at the same time. The LED reaction speed is fast. Using RGB three-color LED with fast reaction liquid crystal, the color sequitual method can be used to omit the use of color filter.

The luminous efficiency of LED is only 20 ~ 40lm / W, which is not as good as 80lm / W of CCFL. At the same time, the high cost will be the biggest weakness of LED backlight module. The unit price of a CCFL and a high brightness LED is around $1.50, but the number of LEDs is much higher than that of CCFL. In addition, the LED heat dissipation is poor. The use of large-size TV needs to be coupled with the heat dissipation substrate, which will be another item. The attenuation speed of each LED color is different, and the color will be uneven in long-term use.