Although we have entered the full screen era of smartphones, to be honest, there is no complete "true full screen" solution on the market, and the shaped screen destroys the screen. Aesthetics, the mechanical structure not only has wear life problems, but also reduces the efficiency of use, and also forces the fuselage to move toward a more heavy direction. The most typical problem is concentrated on the hiding of the front camera.
Not long ago, the announcement of OPPO's on-screen camera technology seemed to make many friends see the hope of "true comprehensive": the camera is hidden under the screen and does not affect the screen. The normal display, the front camera only starts working when needed. If this technology can be mass-produced, the overall screen, the weight and thickness of the mobile phone, the airtightness of the fuselage, and the efficiency of the equipment will be improved.
In fact, as early as 2018 In June of this year, OPPO applied for a patent called “Image Processing Module, Camera and Electronic Equipment”. It can be inferred that OPPO has already started to solve the real full screen since last year, and actively carry out related patent reserves. From the figure we can The design principle of the OPPO screen camera is generally seen: the screen of the front camera part can be transparent, and the light-emitting area is filled by the projection component when the camera is not in use.
Now look again, the front camera can be hidden, the handset can be replaced by the screen sound, the light / distance sensor can also be hidden under the screen, then 100% true full screen really wants Is it coming? Actually, even if the camera is in mass production,The screen ratio is not much higher than the current mechanical structure full screen. Because there are still three major technical issues that need to be resolved -
1, screen package
I believe everyone There is such a question: obviously can be done more narrowly, why do Android phones generally have a chin? In fact, it is not that the manufacturer does not want to do the chin, but it must be done. First of all, what needs attention is the packaging process of the screen.
The screen packaging technology used on mobile phones can be divided into three types. One is the COG package, and the driver chip on the screen extends directly, so a chin is needed. To install related components, the early screen package uses this process, such as the iPhone 8; the second is the COF package, a part of the driver chip is made flexible, and some components can be flipped to the lower side of the screen, so that the chin is narrowed. This packaging solution is commonly used in pre-production full-screen phones.
The third is the COP package, which folds the drive components all over the screen and cancels the chin through the folding of the screen. Because the screen needs to be folded, the body will become thicker. At present, this technology can be realized by Samsung. The screen of iPhone X is ordered from Samsung. Why do domestic mobile phones rarely see COP packaging? The reason is also very simple, the price of domestic mobile phones three or four thousand is difficult to digest the high cost of COP packaging.
2, antenna clearance area
Lenovo Z5 conference, Lenovo Group Vice President Cheng mentioned that it is not that you don't want to mention the screen ratio higher, but you don't have to chin to sacrifice the call. The reason is that almost all smartphones require a signal headroom to ensure the omnidirectional communication of the antenna.
In detail, conductive metals can reflect, absorb, and cancel electromagnetic waves.Therefore, the mobile phone antenna should be set to timed, not only to keep away from metal components, but also to isolate battery, oscillator, shield, camera and other noise reduction. Parts. This clean area where the antenna is placed is the clearing area of the antenna. The screen is equivalent to the metal layer, and the electromagnetic radiation generated by the working process covers the working frequency band of the antenna, so the increasing screen ratio and the sufficient signal clearance area form a contradiction.
In general, the longer the antenna, the lower the channel. After the space of the antenna is squeezed, the low frequency is most affected, resulting in a narrower total bandwidth. In the future, 5G technology has a lot of demand for low frequency. To ensure signal strength, multi-antenna participation is required.
So how does iPhone X do chin? It is understood that the iPhone X balances the signal loss by using a lower electromagnetic loss LCP antenna substrate. But the actual signal of the iPhone X, the listing is so long,I believe everyone is also aware of it. The reason is that in addition to Apple's use of two brand basebands to reduce the performance of the baseband, personal speculation, this and the redesign of the signal clearance area can not be separated.
3, screen BM area
In fact, even after solving the screen package and antenna clearance The problem of the district, the full screen of the mobile phone is also difficult to achieve 100% screen ratio.
Nubian phones have a concept called no borders on both sides. Reflected in Nubian's flagship machine, it does appear to have a left and right borderless visual effect. But in fact, the left and right borderless frame also has a border, but the black side of the screen is very narrow, and a good visual mask is achieved by 2.5D glass refraction. This black border, commonly known as the BM area, is still unresolvable.
It’s very difficult to fully assemble the LCD screen screen.These errors can cause bright edges around the screen, which is commonly referred to as screen leakage. The role of the BM area is to prevent light leakage. In addition, another function of the BM area is to accommodate the peripheral circuit connecting the pixel and the control unit, which is also a self-illuminating OLED screen without light leakage, but also has a black screen s reason.
So, a screen that accounts for 100% of the screen is basically impossible in the current technology. Seeing this, I believe that readers and friends will not be deceived by the manufacturer's renderings or the news.