Phone screens of the future might be squishy

Online doom scrollers of the future could one-day add a new physical dimension to their arsenal of tapping and swiping. Researchers from the University of Bath recently developed a new “deformable,” silicone-based touch screen capable of altering its shape and stiffness when users apply various levels of force to it. The screen, which they refer to as “DeformIO” in a paper published in the Association for Computing Machinery, uses pneumatics and sensors to register levels of pressure applied by a finger and then physically collapses around it. Though the pliable screen is still nascent, researchers involved in its development say it could one day add a new input layer to mobile devices that could be used for a wide variety of use tasks, from navigating between digital maps to playing games and “feeling” the stiffness of products virtually. 

“Though DeformIO isn’t the first deformable screen it is the first to leverage pneumatics and restive sensing,” University of Bath Computer Science Professor and study lead author James Nash said. “In other words, DeformIO allows users to perceive richer, more tactile and natural feedback as they press into the elastic surface.”

How does the deformable screen work? 

Past attempts at creating tactile, pressure responsive screens relied largely on re-configurable panels and raised pins lying just below the device’s surface which lower when pressure is applied. That form factor was limiting, Nash and his co-authors write, because it would lead to sharp breaks between areas of the screen where pressure is applied and others where there isn’t. In this case, DeformIO can apply multiple force inputs simultaneously on various parts of the screen. This novel technique means users can experience a sensation of continuous, uninterrupted tactical response while moving their finger across the screen. This particular screen is 3 mm thick with a 140 mm2 surface layer. 

That innovation in screen design was made possible by utilizing a combination of pneumatics and “resistive sensing” to detect various levels of pressure. Resistive sensing refers to a technique where physical forces, i.e. those applied by a user’s finger, are transformed into electrical signals understandable by a device. Those inputs allow the screen’s silicon surface to dynamically switch between stiff and soft depending on the amount of force the end user applies. Users can apply force to multiple areas of the screen at the same time, which the researchers claim results in a seamless, continuous flow from one part of the device to another. Nash says that tactile flexibility ultimately adds a new layer of interfacing with devices without sacrificing the usability and familiarity of current glass touchscreens. 

“It [DefromIO] gives the same benefits as today’s glass-based screens—which allow you to control your device by moving your finger fluidly across the surface—but with the added benefit of a person being able to use force to interact with their device at a deeper level,” Nash said. 

Deformable screens could add new layer of dimensionality to every-day computing 

If deformable screens ever do make it to mass consumer mobile devices, they could alter the way users interact with apps and services used on a daily basis. The researchers imagine a scenario where a future traveler equipped with a deformable screen uses it to navigate between sections of a digital map. In this example, the traveler could quickly flip between the road view portion of a map and satellite view by simply applying more and less pressure on the screen. That same traveler, the researchers argue, could use the deformable screen tech to fire projectiles at enemies in a mobile game on their way to the airport. App makers, meanwhile, could design software to utilize the screen to add a tactile sensation to simple actions like deleting files or navigating keyboards.

In another example, the researchers displayed an image of a mattress on the screen along with a slider ranging from soft to stiff. When the slider is set all the way to the left in the “soft direction” the screen easily deforms around the user’s finger, mimicking the bouncy sensation of a soft mattress. When the slider is moved to the stiffer setting, the device firms and up more closely resembles flat screens on current phones. The silicon screen could also be deployed in car touchscreens to provide drivers with more inputs they can use without needing to take their eyes off of the road for long periods of time. One day, the researchers imagine, drivers could potentially use the screen to adjust temperature controls or to physically feel topographical data on digital maps. 

“You’d get an enormous amount of information from your map,” Nash said. “For instance, by pushing into a city, you’d get instant demographical data, and by pressing on a specific shop, you’d know from its level of stiffness if it was open.” 

“You’d be directly manipulating a digital object the way you normally would a physical one,” Nash added.

To test the screen, the researchers used a robot arm to measure the screen’s surface stiffness, force sensing accuracy, and touch sensing. A 3D printed ellipse was attached to the end of the robot arm to mimic a human finger. After that round of testing, human reviewers were brought in to analyze potential user experiences too difficult to quantify with robots alone. The human testers were tasked with applying pressure to two separate points on the screen at the exact same time. That test showed users could seamlessly move between multiple pressure points on the screen. Similarly, testers were also able to accurately identify when one section of the screen was made stiffer or softer than another part. The humans were able to perform common swipe and drag gestures with various levels of force and screen stiffness. 

New touch interfaces could face resistance from device users more comfortable with established glass screens. 

It’s worth emphasizing that the screen developed by the University of Bath researchers is still a prototype, and likely won’t make it into the hands of the average consumer for at least another decade. Even if technical and scalability issues are addressed, it’s unclear whether everyday mobile phone users will find the new use cases afforded by the deformable screen compelling enough to switch away from tried and true glass touchscreens. Less novel mobile design interfaces, like foldable and scrollable screens, have already existed for years but  have struggled to gain high levels of adoption outside of niche audiences. It’s possible screens requiring users plunge their fingers into a jelly-like surface could meet similar fates. The tackle nature of deformable screens could also run counties to device manufacturers’ current efforts to make devices thinner. 

“We hope that in 10 to 20 years’ time, the concepts it embodies could be in your mobile phone,” University of Bath Computer Scientist Professor Jason Alexander said in a statement. “For now, we’re exploring the applications it might be best suited to.”