Many people can tell the difference between LCD screen and AMOLED screen, such as what contrast, saturation, maximum brightness, etc., but these are actually external differences, the difference between LCD screen and OLED screen is one-” Can it be fine-tuned to pixel-level light control?”
Why does the saturation of the OLED screen look high? In essence, because of its high contrast ratio, the upper limit of its contrast ratio is almost hundreds of times and thousands of times that of LCD screens. Why? Because the OLED screen directly turns off the pixels in the area when it displays black, it is simply like turning off the lights. The black achieved in this way is serious black. His theoretical contrast ratio is Infinity, the contrast is high, the contrast between light and dark is stronger, and the visual impact is stronger.
The LCD screen does not work, because at this stage, our common LCD screen achieves black by means of masking. In simple terms, it is to wrap a layer of black cloth on the light bulb, and the resulting black is not the most extreme black. , but a dark gray, so its contrast is not that high, basically only a few hundred to one or a few thousand to one.
As shown in the figure below, this is the comparison between an LCD screen and an OLED screen in a real black background. It can be seen that the black of the LCD screen is more of a gray, while the black of the OLED screen is pure black (the lights are all black). Is it not pure if it is turned off?)
The reason is actually very simple. The light emitted by the LCD screen is realized by a backlight layer covered with LED lamp beads. The LED lamp beads of the traditional LCD screen are very large, and it is difficult to achieve fine area control. light, so there is no way to achieve high contrast.
Most of the disadvantages of the current LCD screen are directly related to this reason – low contrast, light leakage, high latency, low maximum excitation brightness, and the reason why it cannot be applied to screen fingerprints and off-screen camera phones. It is precisely because of this that LCD screens have almost been completely abandoned in the high-end market.
Although LCD screens also have some advantages that OLED screens do not have, such as no low brightness stroboscopic, higher display fineness at the same resolution, longer life, etc., but these advantages have been with the rapid development of OLED screens. Not so powerful anymore.
However, this does not mean that LCD screens have no future, because the technology of MINI LED screens is gradually maturing.
What is MINI LED？ in simple terms, it is to make the lamp beads on the LED lamp bead layer behind the LCD screen as small as possible, usually about 50 microns to 200 microns, which is much smaller than the traditional LCD screen. , so that the pixel-level regional light control close to the OLED screen (just close to) can be achieved. At present, the most well-known product using MINI LED technology on the market is Apple’s new iPad Pro 2021 12.9-inch version, which has 10,000 built-in LEDs. LED lamp beads realize independent light control in 2500 areas.
To put it simply, the current MINI LED also has the function of directly turning off the light source when displaying a black background, so that a higher contrast can be achieved. I will directly quote Zhong Wenze’s video comparison, you can take a look, the effect is still very obvious. of.
However, the current MINI LED screen cannot be accurate to the pixel point after all, so the problem of flooding will still occur, especially when displaying some images with small areas of highlights, as shown in the figure below, after all, it only It can divide the screen into 2000 areas, which is of course incomparable compared to the pixel-level light control of the OLED screen.
However, with the gradual development of MINI LCD technology, the light control area in the future will become smaller and more precise, and it will only be a matter of time before reaching the level comparable to OLED screens. At that time, LCD screens will return to history. stage.
In addition, another major advantage of OLED screens is that the substrate can be made of flexible materials, which can be shaped into different forms, such as curved screens, folding screens, etc., and the current flexible OLED screen technology is very mature, and the cost of mass production is also high. Very controllable. But that doesn’t mean LCD screens can’t. As shown in the figure below, this is the flexible LCD screen technology demonstrated by CSOT.
However, the current flexible LCD screen technology is still immature, and mass production is extremely difficult. It will take a certain amount of time to popularize it on a large scale.