Abstract: A resistor electrode type touch sensor having reduced bow of equipotential lines in the sensor and simplified construction. Orthogonal electrical fields are produced on a resistive surface so as to give coordinates of a selected position. Overlying, but spaced from, the resistive surface is an optional flexible conductive pick-off sheet facing the resistive surface which will contact the resistive surface when touched at a selected position. Other elements are described to obtain signals corresponding to the coordinates of a selected point. Electrodes of a selected effective length and spacing to substantially eliminate the bow of equipotential fields produced in the resistive surface are located along selected paths proximate the edges of the resistive surface and attached thereto. Each electrode is connected to a selected connection point along a resistance element along each edge of the resistive to provide selected voltages to the resistive surface.

Abstract: A circular touch sensor having very linear response in a two coordinate system. This circular sensor has four substantially identical and symmetrical quadrants, with points for the introduction of potentials being located at polar and equatorial points on the sensor. The sensor has a uniform electrical sheet resistivity, and each quadrant has a resistance element to distribute the potentials to electrodes connected thereto which are positioned along the perimeter of the circular resistive surface. Individual ends of the resistance element in each quadrant are connected to their respective "tie points" through a resistor of a size to adjust for a proper resistance value between the quadrants at these points. The size (effective length along the position path) of the electrodes in each quadrant generally increases, and the spacing between electrodes generally decreases, symmetrically from the edges of each quadrant toward the center of that quadrant.