Local Dimming
Local dimming is a backlight feature that dims or brightens separate zones of an LCD screen to improve black levels and contrast.
On this page 3 sections
How it works
An LCD screen is lit by a backlight. Without local dimming the whole backlight shines at one level, so a dark scene still glows behind the picture. With local dimming the backlight is split into zones. When part of the picture is dark, the zone behind it is turned down, and when part is bright, its zone is turned up.
Types
- Edge-lit local dimming uses LEDs along the screen edges, so the zones are wide strips and control is coarse.
- Full-array local dimming places LEDs directly behind the panel, so the zones are smaller and control is finer.
What it does not promise
Local dimming does not make an LCD screen as precise as OLED, because each zone covers many pixels. A small bright object on a dark background can show a faint halo, and fast scenes can show zones changing slightly late. The zone count is not part of the name, and a screen that mentions local dimming may have only a few zones. The feature also says nothing about resolution or colour accuracy. How well the zones are controlled also depends on the screen's software, so two screens with similar hardware can behave differently.