Originally Posted by
mikeveal
"Quantum LED"
It really isn't a LED TV it's marketing. Its an LCD.
LED = Light emitting Diode.
LCD = Liquid crystal Display.
LCDs can be transreflective like a watch, or a calculator, or backlit. TV LCD panels are backlit. The LCD then filters the backlight, allowing only the colours you want to see through.
The problem is that the filter isn't perfect. Some unwanted colour always get's through. Blacks are especially noticeable. With the LCD filtering as much of red green and blue as it can, some unwanted backlight still shows and the blacks aren't black.
So rather than have a single backlight for the entire panel, the better LCD TVs use multiple backlights. Then for a dark section of the image they can turn down the backlight as well as filtering with the LCD panel. The problem is that if you have a light section of image and a dark section sharing the same backlight, then the imperfect LCD filter over the dark section bleeds light, giving a halo around the light section of image.
Samsung use lots of small backlights to give better results, they market this as Quantum LED. But the TV is still a LCD TV with a LED backlight, in common with every other LCD TV. It's just marketing spin to make their telly sound more impressive.
A Q-LED TV is an LCD TV. Samsung are not the only manufacturer using multiple small backlights.
Back on subject an OLED TV has multiple discrete organic LEDs per pixel. These different colour LEDs are combined to produce whatever colour or luminosity is required.
Unlike an LCD no unwanted light filters through from the back. The pixels aren't filtering light from behind, they are emitting exactly what's wanted and only what's wanted.
Black portions of an image are truly black. There is no light bleed from light areas to adjacent dark areas and the colours produced are richer and more accurate.
Its a shame the darned things don't last, 'cus they look gorgeous!