01.13.2021 01:58 PM

The Future of Phone Design: Flexible Screens That Roll Up

At CES 2021, two companies showed off concepts for phones with rollable screens. This year, expect this new category of devices to greatly expand.

Image may contain Screen Electronics Monitor Display and Lcd Screen — Photograph: Subject/Object Manifest; TCL

For more than a decade, smartphone designers have stuck closely to the humble rectangular slab. Yet of late, manufacturers are experimenting with wilder forms. We've seen devices with multiple displays, phones of different shapes, and handsets of varying sizes. Last year, Samsung and Motorola made clamshell-shaped flip phones that opened up to look like normal smartphones. Even Microsoft waded into the weird end of the pool with the Duo, a book-like phone with dual displays connected by a vertical hinge in the center.

And now there's a new trend in phone design: handsets with flexible screens that unroll to become larger. The week at CES 2021, TCL and LG both unveiled concepts for new phones with rolling screens.

What exactly is a "rollable"? The form can vary, but imagine having the ability to expand a phone's display by pulling on it vertically or horizontally to increase its surface area. Think of it like removing plastic wrap from its container. That's what TCL and LG showed off. It's not hard to recognize the benefits. Unlike folding phones, which are thick in their closed state since the rigid screens stack on top of each other, a rollable phone can start out slim. An ultra-compact phone with a rollable screen can grow into the size of a traditional smartphone and then shrink back down with a gentle two-handed tug or push.

Roll Call

TCL's prototype phone with a rolling screen.

Video: TCL

These innovations have been in development for years, but they arrive at a time when smartphone sales are in decline. A part of the reason may be the lack of meaningful hardware upgrades year over year, not to mention that people are holding onto their phones for longer. To combat this stagnation phone-makers are hunting for ways to get you excited about buying a new phone, and playing around with display technology seems to be a solution. LG said as much when it debuted the Explorer Project late last year, an initiative meant to "discover yet unexplored usability concepts in an effort to expand the mobile industry."

"We are 100 percent convinced that all these display technologies—foldable, flexible, bendable, rollable—will be quite disruptive," says Stefan Streit, general manager for global marketing at TCL. "If you look back to the last 10 or 12 years, we are all using the same phone; the form factor hasn't changed. Consumers want to have a large as possible display with a small as possible form factor, but there are limitations if you have a fixed display."

The biggest barrier to widespread adoption of phones with these new designs is their high prices. Samsung's first foldable phone launched in 2019 for $1,980. Last year's Z Flip cost $1,380, and Microsoft's Surface Duo sells for $1,400. However, these technologies will start to get a little more accessible this year according to industry analyst Patrick Moorhead, founder and President of Moor Insights & Strategy.

"There is a price issue. I see that coming down this year," Moorhead says. "If there could be some penetration pricing done to get the entry level to $1,000, that would start to drive some considerable volume." Moorhead also expects we will see more of these foldable designs at the Mobile World Congress tradeshow in June. (MWC usually takes place at the end of February in Barcelona, but the show was pushed back to June due to the Covid-19 pandemic.)

Another barrier is reliability. Most high-end single-screen phones these days have durable glass protecting the display, along with an IP68 water resistance rating that protects it from accidental water submersion. Yet the 2019 Galaxy Fold was crippled after specks of dust made their way inside the folding phone's hinge, prompting a delayed launch and forcing Samsung to tweak the hinge mechanism. It was an embarrassing stumble, but things have come a long way in a year.

"When Lenovo came out with the Yoga, it took years for the industry to get better about things like hinges," Moorhead says. "We even saw changes from year to year with Samsung when the second version of the Fold used a brush mechanism, whereas the prior version used a traditional hinge. That might not seem like a big deal, but in the mechanical engineering world, it's huge."

This brush mechanism swept the inside of the hinge clean every time the phone was opened or closed, and it helped prevent debris from sneaking into the Fold 2's internal components. Moorhead expects this year's folding phones to exhibit the same levels of durability we've come to expect from rectangular slab designs. Streit echoed Moorhead's sentiments and highlighted that mechanical engineering is playing an increasing role in smartphone design. "This industry didn't need a lot of moving parts over the past 10 years," he says. "The rollable needs to be a very good mechanical experience that keeps the dirt out."

TCL says it plans to launch a foldable or a rollable phone in 2021, and LG confirmed to Nikkei that the LG Rollable will go on sale this year. None of this is to say that the traditional single-screen phone experience is going away anytime soon. After all, Streit notes that people still buy flip phones today. He also says these new display technologies are "a long-term strategy" for TCL.

Let the Good Times Roll

LG's rolling phone design was teased briefly during its CES press conference. We expect to hear more about it later this year.

Video: LG

We should expect that the first wave of devices with these new rolling displays will not try to incorporate too many new features. Otherwise, phone makers run the risk overwhelming consumers who are used to traditional smartphone designs.

“It shouldn't be too crazy; that's how we came up with the idea about the rollable concept,” Streit says. "It is the same thickness as a regular smartphone, it has the same form factor, something people can use every day. But then when you need a larger display you just roll it out, it's a simple and natural concept."

As for traditional smartphones with rigid screens, don't expect much to change. Bezels around the screens will get slimmer. Colors and finishes will get more adventurous. Buttons and ports may disappear. The notch for the front-facing camera might even disappear too. (Last year, ZTE touted a phone with a selfie camera that hides under the display, eliminating the need for a camera cutout on the front screen. The phone was poorly received.) But by and large, the rectangular phone will stay familiar, safe, and maybe a little boring.

"Once you get to the slab of glass, there's not a whole lot more you can do," Moorhead says. "You can see why manufacturers would be so motivated to find a new form factor. If you run out of reasons to buy something, then the industry tanks."