What Is Local Dimming?
Local dimming is a hardware feature that has many LCD HD displays that allow certain parts of the backlight to be turned off so that the Monitor and TV can show deep black and display deep black and Get a better ratio.
Local dimming is a technique that improves the black surface of your television. The black parts of the screen become extra black with this technique. This article will tell you more about the local dimensions and the different types you can choose from.
As you are probably already aware of its popularity, given the HDR (high dimensional range), it relies on increasing brightness and deep contrast to show an image that is far more realistic. Loving and life-saving that was previously achievable with SDR.
At the same time, it has been said that providing the right HDR experience is not easy, as the display needs to be able to deliver both brightness and good contrast. And that’s where local dimming comes in.
As the name suggests, the local dimming is a feature that allows certain portions of the display’s backlight to be turned off completely and is an important feature for LCD HDR displays.
At the same time, it should be clear why local dimming is necessary when we include the increasing brightness that inevitably equates with HDR. Basically, by turning off the part of the backlight where the black is shown, the monitor or TV manages to achieve a much better contrast ratio than would normally be possible
How many types of Local Dimming
For the most part, the standard of local dimming is reduced to the number of dimming zones that display features mean the number of zones that can be freely turned off from each other. Naturally, the more zones there are, the more accurate the local dimensions can be.
Apart from that, another important factor that can affect the quality of the local dimming is the type of backlight the display uses i.e., whether it is a direct-lit/full array or an edge-lit panel.
In the former case, the LEDs that illuminate the screen are positioned directly behind the panel, while in the latter, the LEDs are arranged along the edges of the screen, as the name implies. Generally speaking, local dimming works better in the case of direct-lit/full array displays since the backlight can be controlled with much more precision.
Direct-Lit Global Dimming
A standard LED LCD with global dimming has a grid of LEDs behind the screen. However, these LEDs cannot be dimmed individually. Instead, the entire screen becomes brighter or darker according to the image. In other words, global dimming means that there is no local dimming and that the black shades on a display will not be too deep.
Full-Array Local Dimming
A display with a complete alignment of the local dimension solution consists of several LEDs located in the entire back of the screen. These zones will dim the part of the screen that needs to be darker without affecting the areas of the screen that need to be illuminated. Fold displays provide the best image quality out of all LED-backlit types, but they are also more costly and heftier in design.
In some scenes where a zone of the LED is lit, but the surrounding areas are dimmed, in some light dim areas a halo bloom effect will cause bleeding, although this is not often the case.
Edge-Lit Local Dimming
Edge-lit displays are placed on the edges of the backlight facing the center of the screen. For this reason, they are cheaper to make and can have very thin designs. The most important disadvantage of edge-lit screens is uniformity and black level in dark scenes because the image is brighter at the edges of the screen and less bright in the center.
LED areas will be dimmed in dark scenes, resulting in deeper blacks than standard direct-lit, edge-lit displays. However, this also introduces additional issues such as obscuring and flowering of moving objects, but it all depends on how local gradation is implemented. Too aggressive local gradation produces more flowering, while too weak local gradation hardly improves the contrast ratio. Depending on the display, there may be a few options available to modify
Overall, full local dimming is the most effective method of improving the contrast ratio on LED displays. While it also significantly increases the price of the display, it is mandatory for the optimal High Dynamic Range (HDR) viewing experience. The local dimming on edge-lit displays can be beneficial, but it can also be unnecessary if poorly implemented. A good direct-lit display without localized dimming is much better than an edge-lit display with low local dimming.