What is local dimming on TV

Local Dimming is a local screen dimming technology used in TVs with LCD, OLED and LED 4K screens. The technology helps to add saturation to black color and thereby improve the quality of the reproduced picture. The technology was developed to improve the performance of LEDs, which do not provide enough depth to blacks.

Why is Local Dimming needed in a device?

On many TVs, black takes on a grayish tint, so many manufacturers are developing new technologies that will improve its contrast. Improving the saturation and depth of black occurs by turning off some of the LEDs.

A 4K TV panel, if necessary, blocks some of the matrix pixels in certain areas of the screen. However, thread blocking is not entirely ideal, so this technology is very important.

The technology allows you to analyze the brightness of dark and light areas, and then adjust the gradation of black shades for each area separately.

Important! If your TV is edge-lit, using local dimming technology may result in flickering, image lag and excessive black depth. There are no such problems with direct illumination.

How to set up Local Dimming

The function can be found in liquid crystal models that have side lighting; in models with direct illumination (including full-matrix 4K models).

Local dimming can reduce the screen area and increase the contrast ratio. The function can work at different levels. On some 4K TVs (LED or LCD), you can alternately turn off the LEDs in the backlight to increase the maximum color depth level. However, in most cases, you can only turn off a small part of the backlight - which leads to a halo effect.

The halo effect is present in almost all TVs because this technology rarely achieves ideal color depth.

Full-matrix 4K displays allow for better dimming. The fact is that in such monitors, many LEDs are responsible for visualizing the image, participating in the formation of the light flux. The LED array is divided into numerous zones.

These LEDs can be turned on and off to suit the user's needs. This feature is called full matrix dimming. Some expensive 4K TVs allow you to turn off each individual LED among thousands of others.

Important! To display the maximum contrast image on the LCD screen, it is best to use this function in a wide range.

OLED TVs have the best implementation of local dimming. OLED technology allows for more precise control of brightness and black depth.

The fact is that they do not have side LED backlighting and an LCD screen. That is why you can adjust the brightness and dimming levels of each individual pixel. Due to these features, OLED screens are superior to their competitors.

Important! This function can either improve or degrade image quality. In some cases, the user may not see any difference at all before and after darkening.

As practice shows, screen dimming is nothing more than a simple marketing ploy. As mentioned above, most users do not notice the difference before and after enabling the feature.