OLED vs LCD. What’s the difference?
LCD screens like those used in previous iPhones and the new iPhone 8 and 8 Plus are built on a backlight—a panel as large as the screen itself that produces a constant white light anytime the screen is on. A series of polarizers and filters are layered in front of the backlight to control the light and produce the image you see on screen. It’s been the dominant technology used in flat-panel displays for almost two decades, but keeping that backlight on draws a lot of power—and that’s a big disadvantage in a portable device.
An OLED does away with the backlight completely. Each individual pixel has a tiny amount of organic material that fluoresces when current flows, so the pixels produce light directly. It’s also possible to control brightness at a per-pixel level.
What’s the advantage of OLED?
The display is typically the most power-hungry component in any phone because of the backlight. By removing it, the iPhone will be more power efficient, which is great for users.
It’s not the only reason to applaud OLED. Getting rid of the backlight allows for the entire display module to be thinner, which is an important consideration in a smartphone. Apple could use the extra space to make the phone thinner or add a little more battery capacity.
Just as important is the image. OLEDs display more vibrant colors, have deeper blacks and brighter whites and a greater contrast ratio so most people find them superior to LCD.
In a completely sane world, madness is the only freedom (J.G.Ballard).