Triboelectrification-enabled thin-film tactile matrix for self-powered high-resolution imaging

Tactile sensors have broad applications in human-machine interfacing technologies. In this work, we report a type of a thin-film-based flexible integrated triboelectric sensing matrix (ITESM) that is of high resolution and large area. It has a total of 3600 sensing units and a resolution of 50 dots per inch (dpi), which are 14 times and 25 times of the state-of-the-art works on the triboelectric sensor array, respectively. When touched by an external object, the ITESM generates a voltage signal in its bit electrode lines and word electrode lines due to the combination of triboelectrification and electrostatic induction. With the assistance of a signal processing circuit that filters and amplifies the electric signal, an average voltage signal of 0.4 V can be acquired. Due to the design of a shielding layer, the electrostatic induction among adjacent electrode lines are effectively eliminated, resulting in a near end crosstalk (NEXT) of merely 0.05. As a result, single-point as well as multi-point contacts can be explicitly revealed. Therefore, the ITESM in this work presents a major step in the direction of high-resolution and large-area triboelectric sensing.