In order to let everyone have a more intuitive understanding, we used a LCD screen mobile phone and OLED screen mobile phone for comparative testing. From the comparison video, we can see that under normal brightness, the OLED screen and the LCD screen
do not “appear” to the screen flashing problem, while in the low brightness case, the LCD screen
has no change, and the OLED screen has a very serious screen flashing phenomenon. (It can be seen that using an OLED screen phone at night will hurt your eyes).
The reason why this happens is directly related to the working mechanism of the OLED screen. We know that because of the self-illumination characteristics of pixels, OLED screens can only adjust the brightness by constantly switching the pixels (ie, PWM dimming mode), which is the root cause of the screen flash.
The brightness of the LCD screen only needs to adjust the brightness of the screen backlight, so there is no screen flash. Even at night, it is still safe and eye-protecting.
Let's go back to the DC dimming technology mentioned in the opening paragraph. Is DC dimming useful? The answer is yes. However, from the current strategies of various manufacturers, most of them switch to DC dimming only in low-light environments. However, how to define a low-light environment? There is currently no uniform standard. So even though many smartphones support DC dimming, we still feel eye discomfort. Therefore, in addition to the "self-contained DC dimming" screen, the dimming mode of the OLED screen switching between DC dimming and PWM dimming is of little significance.
In addition to screen flash, OLED has a fatal flaw - burnt screen. The so-called burn-in screen means that the screen displays a still picture for a long time and leaves an image phenomenon that cannot be eliminated. In the early days of OLED screens for smart phones, the problem of burn-in was extremely serious. Then, with the continuous advancement of technology, has the problem of burn-in been solved? If you pay attention, you can carefully observe the display mobile phone (iPhone X and later OLED mobile phone) in the Apple Display Store. Due to the long-term bright screen placement, when switching to the white background interface, you can often see that the desktop icon is still not completely The state of disappearance (as shown below), this is called "burning screen".
Here, we have selected four mobile phones, both LCD screen phones and OLED screen phones. From this we can clearly see that the OLED screen mobile phone that has been used for one month has not burned out, but the OLED screen mobile phone that has been used for two years has already seen obvious burn-in phenomenon. The LCD screen
mobile phone that has been used for two years is consistent with the one-month LCD screen mobile phone, and there is no burning screen.
We have further processed the picture so that we can see more clearly that the screen of this OLED phone can clearly distinguish the words “returning to the city” and “recovering”. This is because the OLED mobile phone is used all the year round to play the “Glory of the King”. "The vivid imprint left behind."
It can be seen that although the technology is constantly improving, the problem of burn-in of the OLED screen has not been solved. The reason why OLED screen burns is actually caused by premature aging of some pixels, and the problem of burn-in of OLED screen is even more inevitable. At present, smart machine manufacturers can only rely on algorithms to delay this problem as much as possible. Benefiting from the working mechanism (no premature aging of some pixels), the LCD screen will not appear to burn the screen, the working life is guaranteed, even if it is used for many years, it will be "healthy".
Through the above video and the analysis of the principles behind it, we can know that the current mobile phone with OLED screen will still suffer from screen flash and burn-in problems. Although there are already some methods of mitigation, it is always a temporary solution. In contrast, LCD screen
phones do not have these problems at all, not only have a long life, but also more eye protection.