OLED True Dark Mode
Layer 02 // Power & Phosphors
Power Consumption
Unlike LCD panels which use a universal backlight that is always on, OLED displays power each pixel individually. A pixel rendering pure black (#000000) is physically turned off. This results in up to a 63% reduction in power consumption compared to a pure white display.
Smearing Effect
When a pixel is turned entirely off, it takes a non-zero amount of time (latency) to power back up to render a moving object (like scrolling text). This creates "OLED smearing"—purple/black trails behind moving UI elements.
Mitigation
To avoid smearing while still saving power, many interfaces use a very dark gray (e.g. #111111 or #0a0a0c, as used on this site) which keeps the pixels slightly energized.