The array technology shows promise because – unlike currently used touch sensors for graphics – the array can show location and amount of pressure while being transparent and consuming less power than conventional pressure sensors.
The research was led by Professor Jang-Ung Park of Materials Science and Engineering and his research team at Ulsan National Institute of Science and Technology (UNIST) in South Korea. The team used transparent graphene transistors with air-dielectric layers and an elastic body capable of trapping air on one side of the foldable substrate.
The array was able to detect swiping and tapping and finger pressure deformed the air-gap dielectric providing a measure of the amount of pressure and the location. Moreover, when compared with the passive-matrix type, it consumes less power and has a faster response time.
The sensor is capable of simultaneously measuring anything from less than 10 kPa, such as gentle tapping to more than 2MPa, such as human body weight and could be applied to 3D touch panels or running shoes. The results of the study have been published in the April edition of the journal Nature Communications.
Related links and articles:
Shin, S.-H. et al. “Integrated Arrays of Air-Dielectric Graphene Transistors as Transparent, Active-Matrix Pressure Sensors for Wide Pressure Ranges”, Nat. Commun. 8, (2017).