US Patent 7218314 Coordinate input device

A coordinate input device includes a coordinate input element. The coordinate input element includes a transparent coordinate detector and a controller having a control circuit which drives and controls the coordinate detector and which corrects electrostatic capacitance noise disturbing the coordinate detector. The coordinate input device also includes a liquid crystal display device provided on the back side of the coordinate input element, a casing for holding the coordinate input element and the liquid crystal display device, and an L-shaped and a reverse L-shaped push button switches provided on the upper surface of the casing.