One of the major challenges in wearable Health Tech devices is to find a way to communicate information to the wearer. Wireless data connections such as Bluetooth and haptic vibrations are two commonly used methods, and some devices have an integrated LED or OLED display. But what if you wanted to make a smart garment that did not require other components to provide feedback from wearable sensors? Researchers have been working to incorporate displays into fabrics, with varied success. One typical approach is to create a separate flexible display and then laminate it onto a textile surface.

Researchers at the Korea Advanced Institute of Science & Technology (KAIST) have been working on fabric displays for years. Their recent efforts have focused on incorporating OLED materials directly into the textile materials. Since cloth typically has a lot of open space and curved strands of thread or yarn, it provides a naturally flexible and stretchable substrate with large amounts of surface area. Among the challenges, however, is the problem of encapsulating the OLED material so that it is not damaged by exposure to oxygen or water vapor. The KAIST scientists have developed an encapsulation technology that appears to outperform other approaches, and is able to bend to a radius as small as 2 mm. Compared with OLED devices fabricated on plastic substrates, the textile displays are far more durable.

OLED technology is particularly suitable for smart garments, as it is both a thin-film display and emissive (it generates is own light). If this new approach is durable, it could mean that we could literally wear a display of our heart rate on our sleeves.