Samsung's stretchable electronic 'skin' can detect and display your heartbeat

Beyond its next-gen foldable screens with new form factors, Samsung is working on displays that are a lot more flexible. As part of its latest breakthrough, the Korean company says it's developed an OLED skin display, with a built-in heartbeat monitor, that can be stretched by up to 30 percent.

According to Samsung, the early-stage tech provides more accurate measurements than existing wearables for longer periods of time. Notably, the electronics giant is convinced that its trials can pave the way for the commercialization of stretchable devices with large, high resolution screens — which it expects to crop up in all manner of healthcare products.

As detailed in a new peer-reviewed study in the journal Science Advances, a team of researchers from the Samsung Advanced Institute of Technology (SAIT), the company's R&D hub, have created a wearable with a flexible screen that provides stable measurements even after being stretched 1,000 times.

As you'd expect, most fixed-form devices typically break down or fall apart under such an intense amount of physical manipulation. To overcome that technical hurdle, the researchers replaced the plastic material used in existing stretchable displays with elastomer — an advanced material with high elasticity and resilience. They then tweaked its molecular composition in order to boost its resistance to heat and to alleviate the stress caused by elongation, allowing them to integrate a semiconductor into their gadget.

The team also applied a stretchable electrode material (cracked metal) that resists deformation to the elastomer area. According to researcher Yeongjun Lee, this "allowed the spaces and wiring electrodes between the pixels to stretch and shrink without the OLED pixels themselves becoming deformed."

By making the elastomer more resistant to chemicals and heat, the team say they've effectively demonstrated that stretchable devices can be fitted with health-tracking sensors and semiconductors — similar to the ones found inside current wearables like the Apple Watch.

Going one better, they claim their flexible device adapts better to movement by fixing to the wearer's skin. This makes continuous heartbeat measurements possible with a greater degree of sensitivity. During their trials, they found that wrist movement didn't cause any deterioration to performance, even as the device was stretched by up to 30 percent. And, despite the activity, it apparently managed to pick up a heartbeat signal that was 2.4 times stronger compared to a fixed silicon sensor.

For now, the team are heading back to the lab to upgrade the tech's resolution, flexibility and tracking accuracy to a level fit for mass production. In the future, they foresee the flexible displays being used to monitor peripheral oxygen saturation, electromyogram readings and blood pressure.