Touch panel system utilizing capacitively-coupled electrodes
First Claim
1. A touch panel system comprising:
- a touch panel having a surface which is adapted to be touched by a user and including means providing a resistive substrate which spans the surface of the panel and has two opposite boundaries, and a pair of electrodes which are capacitively coupled to the resistive substrate adjacent the two opposite boundaries thereof so that the capacitance between the electrodes and the resistive substrate remains fixed during system operation;
means for electrically stimulating the pair of electrodes from a source to induce reference electrical parameters within the system through the resistive substrate and the capacitive coupling between the electrodes and the resistive substrate;
means for determining changes in the electrical parameters effected by the touch of a location of the panel surface by the user wherein the changes in the electrical parameters involve the resistances sensed along the resistive substrate between the point of touch and the boundaries of the resistive substrate by way of the fixed capacitive coupling between the electrodes and the resistive substrate; and
means associated with the determining means for generating a signal corresponding to the changes in the electrical parameters effected by the user'"'"'s touch of the panel surface so that the generated signal corresponds to the location on the panel surface touched by the user.
0 Assignments
0 Petitions
Accused Products
Abstract
A touch screen system includes a touch screen having a surface which is adapted to be touched by a user, a resistive substrate which spans the screen and has two opposite boundaries, and a pair of electrodes which are capacitively coupled to the resistive substrate adjacent the two opposite boundaries thereof. The electrodes are adapted to be electrically stimulated from a source to induce reference electrical parameters within the system. Appropriate components are provided for determining changes in electrical parameters at the electrodes as a result of the touch of a location of the screen by the user, and associated componentry is also provided for generating a signal corresponding to the location of the screen touched by the user. The touch screen of the system may be associated with the screen of a CRT for use or placed upon a tabletop for use as a cursor control pad or a keyboard.
-
Citations
23 Claims
-
1. A touch panel system comprising:
-
a touch panel having a surface which is adapted to be touched by a user and including means providing a resistive substrate which spans the surface of the panel and has two opposite boundaries, and a pair of electrodes which are capacitively coupled to the resistive substrate adjacent the two opposite boundaries thereof so that the capacitance between the electrodes and the resistive substrate remains fixed during system operation; means for electrically stimulating the pair of electrodes from a source to induce reference electrical parameters within the system through the resistive substrate and the capacitive coupling between the electrodes and the resistive substrate; means for determining changes in the electrical parameters effected by the touch of a location of the panel surface by the user wherein the changes in the electrical parameters involve the resistances sensed along the resistive substrate between the point of touch and the boundaries of the resistive substrate by way of the fixed capacitive coupling between the electrodes and the resistive substrate; and means associated with the determining means for generating a signal corresponding to the changes in the electrical parameters effected by the user'"'"'s touch of the panel surface so that the generated signal corresponds to the location on the panel surface touched by the user. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
-
-
12. A touch panel system comprising:
-
a touch panel having a surface which is adapted to be touched by a user and including means providing a resistive substrate which spans the surface of the touch panel and has two opposite edges, and a pair of electrodes capacitively coupled to the resistive substrate adjacent the opposite edges thereof so that the capacitance between the electrodes and the resistive substrate remains fixed during system operation; means for electrically stimulating the pair of electrodes from a source so that electrical parameters are induced within the system through the resistive substrate and the capacitive coupling between the electrodes and the resistive substrate; means for determining a single-coordinate location of the panel surface touched by the user by way of the capacitive coupling between the electrodes and the resistive substrate wherein said single-coordinate location is a function of the distance from the panel surface location touched by the user to one of the electrodes of the pair of electrodes, said location-determining means including means for sensing electrical parameters at the electrodes before the surface is touched by the user and after the surface is touched by the user and means for determining differences in the electrical parameters effected by the touch of the panel surface so that the determination of the single-coordinate location of the panel surface touched by the user is a function of said determined differences and wherein the differences in the electrical parameters involve the resistance values sensed along the resistive substrate between the point of touch and the boundaries of the resistive substrate; and means for generating a signal corresponding to the determined single-coordinate location of the panel touched by the user. - View Dependent Claims (13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23)
-
Specification