Fibre-like LED can be applied in wearable displays

This technique had limited applications for wearable displays because they were inflexible and ignored the characteristics of fabric. To solve this problem, the research team discarded the notion of creating LED displays on a plane. Instead, they focused on fibres, a component of fabrics, and developed a fibre-like LED that shared the characteristics of both fabrics and displays.

The essence of this technology, the dip-coating process, is to immerse and extract a 3D rod (a polyethylene terephthalate fibre) from a solution, which functions like thread. Then, the regular levels of organic materials are formed as layers on the thread.

The dip-coating process allows the layers of organic materials to be easily created on the fibres with a 3D cylindrical structure, which had been difficult in existing processes such as heat-coating process. By controlling of the withdrawal rate of the fibre, the coating's thickness can also be adjusted to the hundreds of thousandths of a nanometer.

The researchers said that this technology would accelerate the commercialisation of fibre-based wearable displays because it offers low-cost mass production using roll-to-roll processing, a technology applied to create electronic devices on a roll of flexible plastics or metal foils.

Professor Choi said, “Our research will become a core technology in developing light emitting diodes on fibres, which are fundamental elements of fabrics. We hope we can lower the barrier of wearable displays entering the market.”

The lead author of the published paper, Seon-Il Kwon, added, “This technology will eventually allow the production of wearable displays to be as easy as making clothes.”