Patent ID: 8860692

Claim:
A touch pad for detecting multi-touch comprising: a lower pad layer and an upper pad layer each formed of Indium Tin Oxide (ITO), the upper pad layer being over the lower pad layer, wherein the lower pad layer includes a plurality of lower pads arranged in a first matrix, each of the lower pads being configured to sense a capacitance value caused by the multi-touch, wherein the upper pad layer includes a plurality of upper pads arranged in a second matrix, the second matrix including a plurality of rows and a plurality of columns, wherein each upper pad of the plurality of upper pads corresponds to a set of lower pads, the set of lower pads including at least two lower pads, wherein the upper pads are controlled to sequentially put each upper pad into an open state so that a set of lower pads corresponding to an upper pad that is in the open state senses capacitance values, the upper pads having control lines connected to a control unit, the upper pads being controlled by the control unit to be in the open state or a short state, the short state being a ground state, wherein the lower pads have sensing lines connected to the control unit, a set of lower pads corresponding to an upper pad in the open state being activated to sense the multi-touch, a set of lower pads corresponding to an upper pad in the short state being deactivated, and wherein, when a cell of an upper pad is in the open state, the cell of the upper pad and cells of lower pads corresponding to the upper pad are activated to sense the multi-touch by measuring capacitance values of the lower pads, the cells of the lower pads being substantially parallel to the cell of the upper pad.