What you should know about flexible displays (FAQ)

What do Samsung and LG mean when they talk about flexible displays, and how is that different from a bendable phone? CNET breaks it down.

Jessica Dolcourt Senior Editorial Director, Content Operations
Jessica Dolcourt is a passionate content strategist and veteran leader of CNET coverage. As Senior Director of Content Operations, she leads a number of teams, including Thought Leadership, Speed Desk and How-To. Her CNET career began in 2006, testing desktop and mobile software for Download.com and CNET, including the first iPhone and Android apps and operating systems. She continued to review, report on and write a wide range of commentary and analysis on all things phones, with an emphasis on iPhone and Samsung. Jessica was one of the first people in the world to test, review and report on foldable phones and 5G wireless speeds. Jessica led CNET's How-To section for tips and FAQs in 2019, guiding coverage of topics ranging from personal finance to phones and home. She holds an MA with Distinction from the University of Warwick (UK).
Expertise Content strategy, team leadership, audience engagement, iPhone, Samsung, Android, iOS, tips and FAQs.
Shara Tibken Former managing editor
Shara Tibken was a managing editor at CNET News, overseeing a team covering tech policy, EU tech, mobile and the digital divide. She previously covered mobile as a senior reporter at CNET and also wrote for Dow Jones Newswires and The Wall Street Journal. Shara is a native Midwesterner who still prefers "pop" over "soda."
Jessica Dolcourt
Shara Tibken
7 min read
CES Video
Watch this: First Look at Samsung's Youm flexible display tech

Samsung, LG, and others have been showing off flexible displays and even a prototype phone for years, but it's only now that bendy screens are going commercial.

Samsung's Galaxy Round and LG's G Flex raise a lot of questions about what a flexible display is and isn't, what the word really means, and just what kinds of benefits a bendable display would bring to a smartphone or any other gadget.

We address your burning questions below, but if you have more, drop them in the comments.

What is a flexible display anyway?
Colloquially, "display" means the thing you see when you look at your phone and navigate around. But more technically, display refers to the electronic material that sits beneath the glass or plastic cover (the part you actually touch) and is responsible for lighting up your phone.

So when Samsung and LG (or anyone) talk about a flexible display, they're talking about the organic light-emitting diode, or OLED, layer -- located beneath the cover glass -- that's now made using flexible materials (like plastic) rather than rigid glass.

Companies like LG and Samsung have spent years demoing flexible displays that sit on their own outside of any device. These eye-catching products faithfully show off the interface you're supposed to see -- say a grid of icons -- without bending or breaking. Samsung's Galaxy Round represents the first time that a phone maker is bringing a flexible display to market, followed by the LG G Flex.

How are these screens different than curved screens before?
The Samsung Galaxy Nexus (and Nexus S) boasted a slightly curved screen that was meant to more snugly hug your cheek. In this case, it was the glass top that contoured, not the OLED material below.

Do the Galaxy Round and G Flex bend?
No. Both phones use OLED displays that are capable of operating when arched, but that doesn't mean they're going to flex in your hands. The devices are deeply curved, but the phone's body is rigid and will not bend when you move it.

Then why do people keep saying it's flexible?
Part of the confusion stems from the many definitions of what flexible means. Like we mentioned, the flexion can refer to just the OLED or LCD, to the glass, or even to both.

Samsung's deeply bowed Galaxy Round (pictures)

See all photos

Beyond that, there are many forms that a flexible display can take. In the case of the Galaxy Round and G Flex, the display is conformable, meaning it's not flat. "Contoured" is another word that's often used.

Companies making such devices bend the display at some point, say vertically in these phones, but then fix the whole caboodle in place. Another type of flexibility is "bendable." Think of these sort of like credit cards. They flex a little bit, but don't completely fold in half.

Then there's a third category, foldable displays, which do just what you think. Finally, there are rollable displays, often called the holy grail of flexible displays. To picture this type, just think about a perhaps less extreme version of a scroll, or a Fruit Rollup, and you can see where the concept's going.

Samsung has also showed off foldable displays. Journalists haven't been able to get photos of that out into the wider world, but from descriptions we've read, it sounds like these screens are hinged.

Why would anyone want a flexible display anyhow? What are the benefits?
As CNET has noted before, the benefits for a curved display like the Round and Flex aren't immediately clear, though one could be increased readability and less glare from a curved display.

There are some pretty significant benefits for displays that can flex. For one, they could be less prone to breakage when dropped, largely because they might use plastic, which has some give, instead of glass. Plastic also can make the devices thinner and lighter, and it can allow for products in different shapes beyond the standard rectangular screen.

Note that this may not always be the case. Even plastic can break if you stress it enough, and glass-makers are also designing flexible glass, but more on that below.

Still, the durability issues raises the question: Why not just make a regular phone with a plastic display? We'll likely see that too, some experts say, but there are some things a flexible display can do that others can't.

Samsung's flexible Youm display shows the floppy, functioning OLED at work. James Martin/CNET

Imagine being able to fold up your phone or tablet and put it in your pocket, or unroll a screen to serve as a map. These could even be incorporated into clothing or jewelry or other items where the screen needs to have some give. The future potential for flexible displays is huge if hurdles are overcome, even though we may not yet know exactly what their uses will be.

While some gadget-watchers are incredulous about the practicality of a scrollable phone, others see the benefit in trying to make them anyhow. NPD DisplaySearch analyst Paul Semenza is one of them. "I don't think anyone developing them knows the value of curvature or flexibility yet," he told CNET.

What are the hurdles to making a flexible smartphone?
It takes much more than a bendy screen to make a phone you can flex. Right now, batteries and other circuitry are unyieldingly straight. The durability of a bendable phone and its internal parts are also in question. Depending on the design, you may need to have a flexible display, cover material (like plastic or glass), arching batteries, and forgiving silicon.

Some of this is already in the works. LG announced new battery tech for three kinds of juice packs that can curve, squeeze into tight spaces, and even contort like a pretzel. Time will tell if these produce and hold enough charge to competitively power a smartphone.

Read more on what it takes to make a flexible phone.

In addition, devices can be designed so they have a sort of rigid spine that stores the components that can't be flexed, while the rest of the gadget moves freely. We know that these various flexible designs are possible based on concept devices shown by Samsung and others.

Along with making the guts flexible comes another big challenge -- manufacturing these devices and displays at high volumes. Phones that move will undoubtedly cost more than standard smartphones when they first hit the market, but after the industry nails down more efficient manufacturing, the cost to make the phones will surely drop, along with their sticker price.

Even though the Galaxy Round and G Flex's displays are curved, not bendable, they're undoubtedly still tough to manufacture efficiently at high volumes.

Which is better, flexible OLEDs or LCDs?
When companies show off displays being curved, bent, folded, or rolled, they're typically using OLED. While it's possible to curve an LCD, it's not as easy or as effective as curving OLED, according to the experts we spoke with.