The rally call for scroll screens has been sounded, but how far are they from mass production?

After entering the smart era, mobile phone screens not only carry the basic function of displaying content, but also shoulder the mission of improving user experience. As far as the mainstream screens on the market are concerned, designs such as notch screens, water drop screens, hole-punch screens, and full screens are emerging in an endless stream and have been fully mass-produced. With the increasing perfection of flexible screen technology, it is no longer a fantasy for mobile phones to achieve effects such as retractable, foldable, and rollable.

After Samsung, Huawei, Motorola and other manufacturers launched foldable screen phones, rollable screens have also emerged in the public eye. Recently, OPPO, TCL, and LG have successively released rollable screen concept phones, and the patents and design drawings of Samsung and Huawei rollable screen phones have also been exposed. Although it is still in the research and development test stage, there is no doubt that rollable displays may become the next form of smartphones after foldables.

The scroll screen track sounded the assembly call

OPPO: On November 17, 2020, OPPO officially released the OPPO X 2021 horizontal scroll screen concept phone. The product is equipped with a flexible OLED screen. The initial form is a straight touch phone. When unfolded, the screen can be extended to the size of a tablet. When switching, just slide up on the key area on the right side of the phone to unfold the screen, and slide down to fold it. The minimum screen width is 70 mm, and it reaches 107 mm when fully unfolded. It can be switched freely from 6.7 inches to 7.4 inches, thus realizing the conversion from a small screen to a large field of view and from a mobile phone to a tablet.

In terms of technology, in order to make the screen retract more smoothly, OPPO designed the "Roll Motor" power solution, the "Comb Bed" screen support solution and the "Warp Track" stacking. Through the two built-in drive motors in the body, a constant force is output for the retraction and extension of the screen, ensuring that the screen is evenly stressed during movement and avoiding damage to the screen due to sudden forceful opening and closing. At the same time, to protect the screen, the product is also equipped with a "dynamic frame". When the screen is unfolded, the phone frame and the back glass battery cover will move synchronously with the screen.

TCL: On January 11, 2021, TCL Huaxing Optoelectronics launched two roll-up screens at CES 2021, namely a 6.7-inch AMOLED roll-up screen and a 17-inch inkjet-printed OLED roll-up screen. Unlike OPPO's horizontal roll-up, TCL's roll-up screen adopts a vertical roll-up method. The AMOLED roll-up screen has a screen size of 6.7 inches when stored. There are two electromechanical motors inside the body, which pull out the internal screen by sliding the casing and expand it to 7.8 inches.

It is worth noting that compared with the thickness of folding screen mobile phones, which are often more than 14 mm, TCL has controlled the thickness of the body to within 10 mm, and the thickness of the whole machine remains unchanged during the sliding process, and the curling sliding radius is only 3 mm. In other words, the appearance of the product can achieve a lighter, thinner and smaller volume.

It is reported that the official said that this product has the ability to be mass-produced for commercial use, and its cost is 20% lower than that of its competitors. It has currently contacted domestic and foreign terminal manufacturers and is in the deep adaptation stage.

LG: At the same time, LG also released a roll-up screen mobile phone called "LG Rollable" at CES 2021. The screen size is 6.8 inches in normal state with a resolution of 1080×2428, and it reaches 7.4 inches when unfolded with a resolution of 1600×2428. According to industry chain news, the mobile phone has entered the mass production stage and is expected to be officially released next year or the year after. It is expected to become the first manufacturer in the industry to achieve mass production of roll-up screen mobile phones. Some industry insiders also said that LG may cooperate with BOE to produce based on flexible organic light-emitting diode technology.

In addition, LG has also used flexible OLED panels and launched a liftable rollable TV called LG Signature OLED TV R in its high-end Signature series products. Later, LG may continue to make efforts in the notebook computer field.

Samsung: In fact, Samsung has proposed the concept of a scroll screen for a long time. According to a patent document published by Patently Apple, Samsung may be considering developing a scroll-shaped flexible screen device. From the concept map currently exposed, the screen of the device can be hidden in the cylindrical space and can be pulled out when in use. If successfully put into production, it may be used for mobile TV.

There are also reports that this scroll phone is similar to a traditional slider phone. Users only need to gently hold the upper area to pull out the screen, and the phone screen can be stretched and elongated to become a "long screen" phone. Another prediction is that the scroll screen phone that Samsung is developing is similar to the metal texture design of OPPO X 2021, which can be stretched to the left and right sides, and the screen can be expanded from 6 inches to 8 inches.

Although the exposed renderings are different, it is undeniable that as a first-tier folding screen company, it is only a matter of time before Samsung enters the scroll screen market.

Huawei: As early as the beginning of last year, a designer exposed the Huawei "Mate X 2030" version of the scroll screen mobile phone. This model is based on the appearance design of Huawei Mate X, adopts a waterfall screen design, the right side of the device can be pulled as a whole, and will be equipped with an M Pen stylus. When users need to make pictures, they can adjust the screen size at any time.

On the whole, under the premise of a significant improvement in upstream material technologies such as flexible screens and hinges, major mobile phone or screen manufacturers have also begun to gear up in the field of flexible screens. According to Strategy Analytics, the shipment of flexible screen mobile phones will show a step-by-step growth in 2021 and 2023, reaching 30.4 million and 50.1 million units respectively. Although foldable screen mobile phones have not yet been mass-produced for commercial use, driven by technology and hot market demand, many manufacturers have begun to deploy in the field of scroll screens to seize the initiative.

Roll-up screen vs. folding screen: zero crease and thinner

From an intuitive point of view, the biggest difference between rollable screen and foldable screen phones is the screen crease and body thickness.

At present, there are two main forms of foldable screen mobile phones, namely folding left and right and folding up and down. However, no matter which folding method is used, it will leave a relatively obvious crease on the screen, and as the number of uses increases, the crease will also be at risk of damage.

Compared with folding screens, scroll screen phones do not need to be folded, or the creases are cleverly hidden. The crease problem is alleviated by stretching the screen, so the appearance avoids creases and hinge exposure, improving the user's visual experience. At the same time, due to the difference in the way the screen opens and closes, the scroll screen phone is also superior in body thickness. Compared with folding screen phones, it is thinner and lighter, but it still cannot achieve the thinness of traditional smartphones. In terms of product life, the scroll screen avoids direct folding, which also extends the number of times the product is used to a certain extent.

Regarding the body size, Lin Zhi, chief analyst at Wit Display, pointed out that the common goal of foldable and scroll screens is to increase the screen size as much as possible without losing portability. However, the current foldable screen phones are relatively thicker and heavier than smartphones, making it difficult to make them thinner, which has a certain impact on portability.

However, scroll screen phones may face the same problem. Lin Zhi further pointed out: "Because if the scroll cannot be made smaller, the volume will be relatively thick and heavy. But if the volume is too small, the battery life will be limited. So how to make the scroll smaller while maintaining the battery life is also a big challenge for scroll screen phones."

At the same time, judging from the concept models that have been released so far, they are mainly focused on breakthroughs in hardware such as screens, hinges, and covers. As for software adaptation, it is only used in functions such as video playback, camera, and gallery, and more software support solutions have not yet been released. In addition, although TCL and LG both stated that their products have the capacity for mass production, product yield and price are also factors that restrict the popularization of products.

The road to mass production may be full of difficulties

It is undeniable that whether the scroll screen can be commercialized on a large scale, or even replace the folding screen, the product price is also particularly critical. At present, the price of folding screen mobile phones is basically around tens of thousands of yuan, which is still relatively niche for ordinary consumers. At present, it is not realistic to achieve "popularization". Although the scroll screen mobile phone has not yet been mass-produced, it is reported that the price may be higher than that of the folding phone, mainly because the cost is high.

"Although both use flexible screens, foldable screen phones use hinges to achieve folding, while roll-up screens use drive motors and other components with higher precision to achieve screen stretching." Industry insiders pointed out that although the cost of flexible glass cover plates has dropped, the cost of materials such as flexible screens and hinges is still very high. Some supply chain sources predict that the price of roll-up screen phones will exceed 15,000 yuan.