What Is Mini LED?

How it differs from standard LED and Micro LED

LED technology provides backlighting for LCD TVs and PC monitors. However, not all LEDs used in those applications are the same. Mini LED, which is sometimes called "sub-millimeter light-emitting diode," lands squarely between Micro LED and standard LED technologies. Here's a look at how Mini LED works and how it compares to Micro LED and standard LED.

TCL Q82X LED/LCD TV with Quantum Dots and Mini LEDs

Mini LED vs. Standard LED

Mini LEDs work similarly to the LEDs used in LED TVs and QLED TVs, and most PC monitors, but they're much smaller.

LED TVs are LCD TVs that use LEDs as their blacklight system. QLED TVs are LCD TVs that combine an LED backlight system with Quantum Dots.

Standard-size LEDs used in LCD TVs and PC monitors are about 1,000 microns (0.04 inches) in size, while Mini LEDs measure about 200 microns (0.02 inches).

Mini LEDs' smaller size means several thousand can be placed on a backlight panel (depending on the TV's screen size) instead of tens or hundreds of standard-sized LEDs.

However, just like standard-size LEDs, Mini LEDs don't contain image content. Their function is to send light through LCD chips (pixels) containing the image information. Color is added after the light passes through LCD chips to a layer of red, green, and blue filters before reaching the screen surface.

LEDs or Mini LEDs can, at the manufacturer's discretion, be brightened or dimmed (a process called "local dimming") in small groups ("dimming zones") in synchronization with the image information. 

In what's called "edge lighting," some LCD TVs incorporate LEDs along one or more screen edges. "Direct lighting" or "full array backlighting" means a TV incorporates LEDs placed behind the LCD screen layer. When full-array LEDs are placed in zones and dimmed, it's called "full array with local dimming" (FALD).

How Local Dimming and Dimming Zones Work

Local dimming determines how even black-and-white levels are displayed across the screen surface when using LEDs as the light source. If LEDs always remain on and not dimmed, black levels are more like a dark gray. The result is a narrow contrast and color range. 

However, if the LEDs are brightened and dimmed according to the light and dark properties of the image content, then objects that are supposed to be dark will look darker, and areas that are supposed to be white will look whiter. This also helps extend the color range.

Diagram of a Vizio TV's full array LED and Active LED zones.

The precision at which this can be accomplished results from grouping one or more LEDs into a zone. When more zones can be dimmed independently at any given time, images with multiple objects displayed in different parts of the screen can be made brighter or darker as needed.

The Importance of Mini LED

Mini LEDs are important to TV viewers because they add precision to the local dimming process.

TCL Mini LED Chart showing local dimming types for LCD panels and LED backlight

Other tech advancements, such as 4K and HDR, 8K, and expanded color gamut, create more controllable dimming zones, allowing Mini LEDs to make images look even more realistic with light and shade across all objects. Since light and shade also affect color, Mini LEDs help provide more accurate color intensity in both light and dark areas of an image.

Mini LED vs. Micro LED

While Mini LEDs are extremely tiny (approaching microscopic size), Micro LED is an even smaller LED solution.

Micro LEDs are much smaller than Mini LEDs (100 microns/.004 inches or less) and serve an expanded role. 

LED, Mini LED, Micro LED Size Comparison

When used for TV or other video display applications, Micro LEDs are more than just microscopic-sized light bulbs. Each Micro LED produces the light, displays the image, and adds color without the need for LCD chips, additional color filters, or layers. 

A Micro LED pixel is made up of red, green, and blue "subpixels." Micro LEDs can be brightened or dimmed individually or in groups, and also can be turned on or off very rapidly. Micro LEDs closely match the performance of OLED technology used in select TVs marketed by LG, Sony, Panasonic, and more.

Micro LEDs are more expensive to make than LEDs or Mini LEDs. As a result, they are currently applied in high-end applications, such as self-illuminating home video walls, cinema screens in select theaters, and digital signage.

The Bottom Line

Mini LED is seen as an improvement over the standard LEDs used in TVs and PC monitors. It's a more affordable performance solution than TVs and monitors with Micro LED or OLED technology. 

Several TV makers offer TVs with Mini LED backlighting, including TCL, Acer, and Asus.