Will this Stretchable Touchpad Become a Wearable Touchscreen?

That’s what some engineers are hoping for. Researchers from the Seoul National University have created a touchpad using hydrogel — the same substance used to make contact lenses. Hydrogen contains primarily lithium chloride salts, which are highly conductive while allowing for shape retention. The team behind the project believe these unique characteristics could pave the way for a revolutionary new type of touchscreen interface that can be worn on the human body.

Touchscreens are used just about everywhere in today’s world. You can find them in classrooms, homes, cars and workplaces. The problem with touchscreen technology, however, is that it’s not flexible. Because they are typically designed with solid frames and hardware components, they cannot be stretched for use on flexible surfaces. Researchers at the Seoul National University are hoping to overcome this problem with the invention of a new touchscreen device containing hydrogel.

Basically, the new hydrogel touchscreen would operate in a similar manner as a traditional touchscreen device. A small AC voltage would be applied to the device’s corners. And because the hydrogel is conductive, it allows electricity to flow seamlessly across the device’s surface. Now, going back to the basics of capacitive touchscreen technology, touch is identified when a disturbance in the electrical field occurs. Long story short, when a user touches his or her finger to the device’s surface, it disrupts the electrical field, a disturbance that’s used to determine where the touch occurred. The hydrogel-powered touchscreen device is equipped with various sensors that measure the difference in electrical current from each of its corners; thus, calculating when and where a touch occurs.

Researchers demonstrated the hydrogel-powered touchscreen device by drawing stick figures and writing phrases like “Hello world!.” They were also able to play games like chess. Researchers say the revolutionary new touchscreen can be stretched to more than ten times its default surface area, allowing it to wrap around a person’s arm or leg. Several other companies and organizations are also experimenting with flexible, stretchable touchscreen interfaces. The one presented by Seoul National University, however, has garnered mainstream attention due to its use of hydrogel, which isn’t found in any other touchscreen devices.

More so, the touchscreen allows roughly 98% of visible light to pass through it. It’s unclear exactly how this will affect the device’s performance, but it’s certainly an interesting revelation nonetheless.

These findings were published in the journal Science.