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by jseliger 2823 days ago
This is actually a reply to @Romed:

OLED displays have a different problem; they have so much noise at low brightness that the image falls apart. Still, I think a monochrome OLED display is what the person who wrote this article actually wants. It would have better performance in every respect to E-Ink, and it doesn't sound like their application requires E-Ink's low power.

My understanding too is that OLEDs can have "true black" pixels that emit no light at all. For "dark mode" style screens, this is a huge benefit, because the majority of the screen may simply be turned off. Conventional LCD screens still send current to each pixel, but the "black" is simply tuned to a dark frequency, rather than being altogether off.

2 comments

Yes, an unpowered LED emits no light. But an OLED that's barely on, for example at uniform 1% grey looks like crap because of the noise. People describe this as a "texture" or "banding". It's the consequence of trying to drive millions of individual semiconductor devices to the same emissive power. At higher brightness you can't notice the noise.
Lcd screens are transparent and selectively block the light from a backlight. They can’t show full black because they can’t completely block the backlight.