LED背光模組之研究

白光LED 背光模組，藉由串聯電阻方式來控制電流及亮度，看來十分簡單，不過當我們考慮溫度效應時，它比預期的來得複雜些。視覺在亮度不變下，選擇最佳的控制電流，將使得白光LED 背光的液晶面板有更佳的表現。可接受的條件下，透過合理的降低LED 的電流來降低功率耗損，讓LED介面溫度影響減到最小。如此，不僅可以降低背光源的能量損耗，同時也可延長LED的使用壽命。接著，我們進行三色LED探討，當RGB 三色LED 進行調光時，由於紅光LED 是非常純色，然而綠光LED 及藍光LED 發光時，綠光LED 會產生微量藍光，藍光LED 會產生微量綠光，使得混光時造成綠、藍的色座標發生偏移現象。因此，若想有比較好的調光效果必須考量綠光及藍光的色座標偏移才能有更好的調光結果。我們進行三色LED樣品的色座標分析，比對其色域值約是NTSC標準的118%及EBU標準的164%。顯然，三色LED有相當優良色域表現。然而，以TCO’03標準來判斷時，發現藍光色座標超出標準值，顯示藍光部份有待的加強。

關鍵字

白光LED模組；溫度效應； LED色域； NTSC ； EBU ； TCO’03

並列摘要

White LED backlight module, by way of series resistance to control the current and brightness, seems to be very simple, but when we consider the temperature effect, it's more complicated than expected more. No change in the brightness, select the best control of current, will make white LED backlighting LCD panels have a better application. Design while maintaining the same brightness, the LED through a reasonable and lower current to reduce power drain, so to minimize the impact of LEDjunction temperature. Nevertheless, not only can reduce the backlight source of energy loss, but also to extend the service life of LED. Then, we explore the three-color LED, when the RGB tri-color LED to light when the red LED as a result of a very solid color, but green and blue LED light-emitting LED, the green LED will have Blu-ray, Blu-ray LED will be green, the light caused by mixing green and blue color coordinates of the offset phenomenon occurred. Therefore, if there is a better dimming effect must be considered green and blue color coordinates in order to offset the dimming better results. We carry out three-color LED color coordinates of samples analyzed for their color gamut than the NTSC standard value of about 118% and 164% of the EBU standard. It is clear that the tri-color LED considerable performance excellent color gamut. However, to determine TCO'03 standards, it was found that blue light than the standard value of color coordinates, showing part of blue light to be strengthened.