MIT researchers woven LEDs and sensors directly into textile fibers

The British magazine Nature recently published a new research in materials science: the MIT team used a new manufacturing method to directly splicing light-emitting diodes (LEDs) and sensors into textile-grade polymer fibers. The process can be used to develop new wearable technologies that enable optical communication and health monitoring.

Semiconductor diodes capable of emitting or detecting light are essential components of communication and sensor technology. If they can be incorporated into fabrics, it is expected to create new wearable electronic devices. However, it turns out that combining the functionality of semiconductor devices with the scalability of fiber-based textiles is a tricky business.

MIT researcher Joel Frink and colleagues, starting with a larger polymer preform, embedded the semiconductor device into the hollow channel of the preform. Then, the preform is heated and stretched while threading the wire into the hollow passage to form an expanded fiber bundle. In this way, the electrically connected light emitting or photodetecting diodes are evenly distributed axially within the fiber bundle. The process is inherently scalable and can produce functional fibers hundreds of meters long. Once stretched, the fibers can be easily woven into the fabric.

The research team put these diode fibers into a standard household washing machine for ten laps and found that their performance was not damaged, proving their durability. They also showed that a two-way optical communication link can be established between two textiles containing light detecting and luminescent fibers. Not only that, but this smart textile can also be used to measure the wearer's heart rate.

The researchers concluded that this new manufacturing process enables people to create textiles with more advanced features, and that smart textiles and wearable technologies will become more sophisticated in accordance with their own "Moore's Law."