Input system including resistance film touch panel and pushed position detecting device

An input system including a resistance film touch panel and a pushed position detecting device for detecting two-dimensional coordinates of a pushed position of a touch panel based on surface resistance values of resistance films, the system comprising:

• a pair of insulating base layers opposed to each other with a certain distance therebetween;
• a spacer provided between said insulating base layers for keeping said layers apart but for allowing said layers to approach each other when an external force is applied to one of said layers;
• a first resistance film extended in first and second directions and provided on an inner surface of one of said layers, the first and second directions crossing each other perpendicularly and said first resistance film having outer connecting electrodes on both ends thereof along the second direction;
• and
• a plurality of second resistance films provided on an inner surface of the other of said layers, said second resistance films each being a lengthy strip extended in a direction crossing the second direction and having first and second outer connecting electrodes at both ends thereof;
• DC potential supplying means including a first switching means for supplying a DC potential to said second resistance films one by one;
• second switching means switching at a speed at least twice as high as the DC potential supplying means, said second switching means being for supplying a DC potential to the outer connecting electrodes of said first resistance film alternately;
• and
• electric potential measuring means for measuring the potential of the outer connecting electrode of said first resistance film, the electrode being opposed to the electrode supplied with the DC potential by the switching means.

An input system including a resistance film touch panel and a pushed position detecting device for detecting two-dimensional coordinates of a pushed position of a touch panel based on surface resistance values of resistance films, the system comprising:

• a pair of insulating base layers opposed to each other with a certain distance therebetween;
• a spacer provided between said insulating base layers for keeping said layers apart but for allowing said layers to approach each other when an external force is applied to one of said layers;
• a first resistance film extended in first and second directions and provided on an inner surface of one of said layers, the first and second directions crossing each other perpendicularly and said first resistance film having outer connecting electrodes on both ends thereof along the second direction;
• a plurality of second resistance films provided on an inner surface of the other of said layers, said second resistance films each being a lengthy strip extended in a direction crossing the second direction and having an outer connecting electrode at one end thereof;
• DC potential supplying means for supplying said first resistance film with a DC potential through both the outer connecting electrodes thereof;
• a switch switched to a first state of supplying all the other connecting electrodes of said second resistance films with a ground-level potential and to a second state of releasing the same from the ground-level potential;
• and
• electric potential measuring means for measuring the potentials of all the other connecting electrodes of said second resistance films both in the first and the second states.