Coordinate detecting device for outputting coordinate data when two points are simultaneously depressed, method therefor and computer control device

Abstract

In the coordinate detection of resistive film system, detection of the coordinates of simultaneously designated two points is made possible. On a touch panel composed of two conductive films, whether input is made in a point or simultaneously at two points is judged by a current monitor. Simultaneous inputs at two points decrease the apparent resistance of the conductive film, and can be detected by an increase in the current. If the input of a point is identified, the coordinate data of the input point are retained as latest coordinate data in a RAM. If simultaneous inputs at two points are identified, coordinate data are obtained from the coordinate data retained in the RAM and from the potentials in the x and y directions, obtained from two conductive films constituting a touch panel, through amplifiers, and are outputted, together with the coordinate data retained in the RAM, as the coordinate data of the two points.