While conventional Lcd Hdtvs use a fluorescent backlight the Un55B8500 uses an Led backlighting system. An array of bright white Leds behind the Lcd panel illuminates the image. The Un55B8500 also features " local dimming" which means that the brightness level of different sections of the Led array can be controlled independently. This allows the Un55B8500 to display both light and dark portions of the same image with remarkable accuracy for new levels of depth and realism with everything you watch. An Led backlight is also more energy-efficient. In fact Samsungs 2009 Led Hdtvs consume up to 40 less power than last years conventional Lcd sets.