Patent ID: 8159471

Claim:
A coordinate input device comprising: a plurality of detection electrodes which are arranged in a planar shape in a detection area of a substrate; a plurality of routed wires connected to the plurality of detection electrodes; a coating film which coats the plurality of detection electrodes; a detection unit which detects a capacitance variation between the plurality of detection electrodes via the coating film; and a calculation unit which calculates a capacitance forming position from the detected result of the detection unit, wherein the plurality of detection electrodes are formed in the detection area in a first direction and are arranged in a second direction orthogonal to the first direction so as to correspond to a plurality of detection electrode pairs, each of which is composed of a pair of adjacent detection electrodes, a ratio of the width of one-side detection electrode of the pair of detection electrodes to the width of an other-side detection electrode of the pair of detection electrodes corresponding to each of the detection electrode pairs is changed according to the first direction, each of the plurality of routed wires is connected to a respective one of the detection electrodes at an end of the electrode in the first direction and is formed on the same layer as the plurality of detection electrodes, the plurality of detection electrodes corresponding to correction detection electrode pairs, each correction detection pair being composed of the one-side detection electrode corresponding to a detection electrode pair and the other-side detection electrode corresponding to another detection electrode pair adjacent to the one-side detection electrode, and the calculation unit comprising: a first coordinate calculation unit which calculates a first coordinate which is a detection position of the first direction, based on a sum of the capacitance variations of the one-side detection electrodes and a sum of the capacitance variations of the other-side detection electrodes; and a second coordinate calculation unit which calculates a second coordinate which is a detection position of the second direction, from the capacitance variations of the detection electrode pairs, the capacitance variations of the correction detection electrode pairs, and the first coordinate.