In a nutshell, LED LCD screens use a backlight to illuminate their pixels, while OLED’s pixels actually produce their own light. You might hear OLED’s pixels called ‘emissive’, while LCD tech is ‘transmissive’.
The light of an OLED display can be controlled on a pixel-by-pixel basis. This sort of dexterity just isn’t possible with an LED LCD – but there are drawbacks, too, which we’ll come to below.
In cheaper TVs and LCD-screen phones, LED LCD displays tend to use ‘edge lighting’, where LEDs actually sit to the side of the display, not right behind it. The light from these LEDs is then fired through a matrix that feeds it through the red, green and blue pixels and into our eyes
