LED backlight technology has many attractive advantages like many new technologies, but LEDs need to solve some technical difficulties in order to occupy the mainstream of large-size LCD backlights. Through the comparison of the table, we have found that LEDs are at a disadvantage in terms of power consumption, in addition to the problems of high cost and poor consistency.
1) At present, the luminous efficiency of LEDs is low, and the power consumption is higher than that of CCFL backlights of the same size. At present, the output luminous flux of CCFL is mostly in the range of 5000 to 7000 lm, and the output luminous flux of the actual screen is higher than 300 lm, and most LED backlights cannot reach this index. However, there are a large number of enterprises in the world engaged in related research, and the LED luminous efficiency is quite fast. At present, the high-brightness LED backlight with a luminous flux of 10,000 lm has also appeared. It is believed that it is only a stone's throw away from maturity; 2) the cost is too high, the price Expensive, equivalent size backlights, LEDs are four times the price of CCFLs. For the current market where price competition is fierce, the manufacturers are somewhat discouraged, and only Sony does not cost for image quality. Of course, as the process matures and the production scale increases, the cost of LED backlight will gradually decrease. 3) The problem of white light consistency with LED as the backlight is a disadvantage compared with CCFL; 4) LED design in dot design The linear light source CCFL is difficult, and it is necessary to consider the attenuation of the light intensity of the LED; 5) The RGB LED backlight will produce a color shift for a long time, and the wavelength will change with temperature to produce different colors.
In addition, heat dissipation, uniformity of the light source, and luminous efficiency of the LED chip are also one of the reasons why LCD panel manufacturers do not use it. At present, there are only a small number of large-sized liquid crystal panel module products that use LEDs as a backlight source. Displaybank said that this is because the price competition in the display field is fierce, and cost reduction must be put first. In the future, the popularity of LED backlights depends on when it can solve the problems of heat dissipation, uniformity and low luminous efficiency of LED backlights.
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TOPCOM Lighting Co., Ltd. , http://www.lightingifts.com