Local Dimming Zones: Full-Array vs Edge-Lit (2026)
Full-array local dimming decides how good an LCD TV's black levels really look, and zone count is where the marketing gets slippery. Here is what matters.
Local dimming is the single feature that separates a punchy LCD picture from a washed-out one, and it is also where TV spec sheets do their best lying. Two sets can both claim "local dimming" and look nothing alike in a dark room.
Quick answer
Local dimming lets an LCD TV brighten and darken separate regions of its LED backlight so blacks look deeper and highlights pop. Full-array local dimming (FALD) places LEDs in a grid behind the whole panel and splits them into many independent zones, giving precise contrast. Edge-lit dimming lights only the screen borders and can dim only large columns, so it blooms more and controls contrast poorly. For dark-room movies, more zones almost always beat fewer.
Key takeaways
- Full-array beats edge-lit because LEDs sit behind the whole screen, not just the edges.
- Zone count matters, but placement and processing matter just as much.
- Edge-lit dimming blooms: bright objects on black leak a halo of light.
- OLED needs no local dimming since each pixel makes its own light.
- Marketing inflates the numbers, so read independent measurements, not the box.
What local dimming actually does
An LCD panel cannot make its own light. It works like a stencil in front of an LED backlight, twisting to let more or less light through for each pixel. The problem is that the liquid crystal never fully closes, so some backlight always leaks through, which is why a plain LCD shows dark gray instead of black.
Local dimming attacks that leak at the source. Instead of running the backlight at one uniform brightness, the TV splits it into regions and dims the ones sitting behind dark parts of the image. Less light behind a shadow means less leakage, which means a deeper black. Do it well and contrast jumps dramatically. Do it badly and you trade one artifact for another.
Full-array, direct-lit, and edge-lit
Three backlight layouts show up on spec sheets, and they are not equal.
| Backlight type | LED placement | Dimming ability | Typical price tier |
|---|---|---|---|
| Full-array (FALD) | Grid behind entire panel | Many independent zones, precise | Mid-range to flagship |
| Direct-lit | Grid behind panel, few or no zones | Coarse or none | Budget |
| Edge-lit | Strip along the edges | Large columns only, imprecise | Budget to mid |
The confusing pair is direct-lit versus full-array. Both put LEDs behind the panel, but direct-lit sets often use very few LEDs and either skip zone control or offer only a handful of zones. Full-array is the version you want: enough LEDs, grouped into enough independently controlled zones to track the image.
Edge-lit is the weakest for contrast. Because the LEDs sit along the borders and fire across the panel through a light guide, the TV can dim only broad vertical or horizontal bands. A single bright star on a black sky lights up an entire column.
Why zone count is not the whole story
Zone count is the number everyone quotes, and premium 2026 mid-range sets now ship with several hundred to a few thousand zones. More zones mean each region is smaller, so the TV can darken a shadow without dimming the bright object right next to it. That reduces blooming, the halo of stray light around bright objects on dark backgrounds.
But raw zone count can mislead. A TV with 1,000 sloppily driven zones can bloom worse than a 500-zone set with smart processing that ramps brightness gradually and predicts motion. The algorithm deciding how aggressively to dim each zone is as important as how many zones exist. This is why two sets with similar zone counts can look different, and why independent measurements beat spec sheets.
The blooming and crush tradeoff
Aggressive dimming fights blooming but risks black crush, where near-black shadow detail gets swallowed as the zone dims too far. Gentle dimming preserves shadow detail but lets highlights bloom. Every local-dimming TV lives somewhere on that spectrum, and the good ones let you tune it. If your set has a "local dimming" menu item, "High" chases contrast, "Low" or "Medium" preserves detail and reduces distracting halos in letterbox bars.
How this fits into a buying decision
Local dimming interacts with the panel technology you choose. If you are weighing LCD variants against each other, our QD-OLED vs Mini-LED TV buying guide covers where each wins. Mini-LED is simply full-array with much smaller LEDs, which packs in more zones for tighter control.
Local dimming also only pays off if you understand how bright the set gets, since dimming controls contrast and peak brightness controls how far highlights pop. Our explainer on TV brightness, nits, and HDR pairs naturally with this one. And once the set is home, your picture menu decides how the dimming behaves, so run through calibrating a 4K HDR TV before you judge it.
What to do right now
If you are shopping or tuning a set you already own, work through this list:
- Prefer full-array or Mini-LED over edge-lit if dark-room contrast matters to you.
- Ignore the marketing dimming name and look up the measured zone count from an independent test.
- In a dim room, watch for blooming around subtitles and bright objects on black.
- If your TV has a local dimming setting, try Medium first, then adjust to taste.
- Remember that OLED sidesteps all of this by lighting each pixel individually.
- Do not judge black levels in a bright store; evaluate in the room you actually watch in.
Frequently asked questions
Is edge-lit local dimming worth having at all?
It is better than no dimming, but only slightly. Edge-lit can darken broad bands of the screen, which helps overall contrast, but it cannot isolate small bright objects, so blooming stays obvious. If contrast is a priority, treat edge-lit as a compromise, not a feature.
How many dimming zones do I actually need?
There is no fixed threshold, because zone quality varies. As a rough guide, a few hundred well-driven zones on a mid-range set gives a visibly better picture than a handful, and flagship Mini-LED sets with thousands of zones approach OLED-like control. Read a measured review rather than trusting the count alone.
Does local dimming cause flickering?
It can, on aggressive settings, especially when bright objects move across dark backgrounds and zones ramp up and down quickly. If you notice pumping or flicker, lower the local dimming setting a notch. Good processing minimizes this, which is another reason it varies by model.
Do OLED TVs have local dimming?
No, and they do not need it. Each OLED pixel emits its own light and switches fully off for true black, so there is no shared backlight to dim in zones. That is why OLED has no blooming, though it competes on other tradeoffs like peak brightness.
