Sparse touch sensing for capacitive touch screens

Improved capacitive touch screen responsiveness can be achieved at the expense of the touch screen controller analog hardware complexity and power consumption. This paper proposes a compressive sensing based approach to exploit the sparsity of simultaneous touches (e.g., 10 or less per person) with respect to the number of sensor nodes (e.g., 100s) to achieve similar levels of responsiveness with lower levels of analog complexity and power consumption. This is done by showing that the number of measurements required for touch detection is related to the number of touches rather than the number of nodes.