How Exactly Do Foldable Smartphones Work?
Foldable smartphones are no longer just conceptual screens that we see at CES or mobile conferences, as they are actually available today. Tech giants like Samsung, Motorola, and Huawei have recently announced or released their own line of foldable phones.
Samsung released the Galaxy Z Flip and, earlier, the Galaxy Fold – which had issues of its own. Similarly, Huawei’s 2-in-1 smartphone and tablet Mate X has recently been made available in India. Other brands like OPPO, Nubia, Lenovo, and Xiaomi are also expected to manufacture their own line.
While Apple and Google have both filed patents that pertain to foldable screens, they have yet to reveal similar foldable smartphones. However, Android’s support for foldable phones shows that these screens are the future of smartphones. But, how exactly do they work? Smartphones are irrefutably the single biggest innovation that has changed the way we live, and just in the past decade.
The devices in our pockets have drastically changed from simple call or text tools to becoming our very own mobile office, entertainment hub, and a lot more. This is why it's no surprise that around one in four adults in India owns a smartphone – and this number is growing by the day. But smartphones today look much like how they looked a decade ago, just with better screens, fewer bezels and higher quality materials.
That is until the recent foldable phones were developed. Flexible screens are nothing new. In fact, the first of them appeared more than five years ago. But they’re not as remarkable as today’s phones that can fold in half, since most of them only had curved edges. We first saw this technology when Samsung unveiled the Galaxy Edge series that would, later on, become the norm for the brand. What’s happening now is that screens don’t just have curved edges, but can actually be folded. Flexible OLED Screens Most of the screens we use today are LCD screens that are built around a glass space.
For OLED screens, the pixels and display image are actually inside the screen technology. The foldable display is a thin layer of plastic – that’s why you can bend it. Getting that technology to larger screens today, however, is a little expensive, which is why most of the foldable phones available are on the pricier side. One huge challenge with the technology is that there’s no glass layer that’s protecting the screens from the external environment.
This means that when you touch it you’re interacting directly with the OLED screen without any layer of glass protection, which could make the screens much easier to damage. Beyond the screen Behind the screen, the printed circuit boards (PCBs) that are being used are also evolving. Traditional smartphones use rigid PCBs in order to hold most of the components in place – making our phones more compact and thinner, but also more powerful.
To accommodate the increased size and flexibility, foldable smartphones employ flexible boards, rigid-flex boards, HDI (high density interconnect) boards and substrate-like PCBs. These allow the new foldable phones to have as many components as their predecessors, since using rigid flex and multi-board designs means they don’t have to be thicker than the average smartphone. The rigid layer can carry the bulk of the components, while the flexible layers allow for interconnections, making the hinge between screens possible.
These new innovations for printed circuit boards are only expected to skyrocket as the foldable phone technology improves. Another unique challenge that needs to be solved for foldable phones is battery life. With larger screens and fewer places to put batteries in, some are concerned about the phone’s longevity. While some manufacturers are solving this by allowing the phones to carry more power, most are waiting for battery technology to catch up. What is clear is that even though we are in the early stages of this new technology, foldable phones are truly taking the smartphone forward.
