Matrix Resistive Touch Panel and Design Method Thereof

• US 20110157082A1
• Filed: 12/27/2010
• Published: 06/30/2011
• Est. Priority Date: 12/31/2009
• Status: Abandoned Application

• Current Assignee: Wintek Corporation
• Original Assignee: Wintek Corporation
• Inventors: Lin, Yung-Chang, Lin, Lin, Lin, Chih-Chiang, Lin, Ming-Chuan
• Application Number:
  US12/978,789
• Publication Number:
  US 20110157082A1
• Time in Patent Office: Days
• US Class Current: 345/174
• CPC Class Codes: G06F 3/045 using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact

Abstract

A matrix resistive touch panel including a plurality of first sensing electrodes, a plurality of second sensing electrodes, a control circuit and a compensating circuit is provided. Each first sensing electrode has a first end and a second end. Each second sensing electrode has a third end and a fourth end. The compensating circuit is electrically connected to the control circuit, the first and the second ends of the first sensing electrodes, and the third and the fourth ends of the second sensing electrodes. The compensating circuit is used for equating a plurality of first impedances between the first ends and the control circuit, equating a plurality of second impedances between the second ends and the control circuit, equating a plurality of third impedances between the third ends and the control circuit, and equating a plurality of fourth impedances between the fourth ends and the control circuit.

Claims

1. A matrix resistive touch panel, comprising:

a plurality of first sensing electrodes disposed in parallel, wherein each first sensing electrode has a first end and a second end;

a plurality of second sensing electrodes disposed in parallel, wherein the extending directions of the second sensing electrodes are perpendicular to that of the first sensing electrodes, and each second sensing electrode has a third end and a fourth end;

a control circuit; and

a compensating circuit electrically connected to the control circuit, the first ends, the second ends, the third ends and the fourth ends, wherein the compensating circuit is used for equating a plurality of first impedances between the first ends and the control circuit, equating a plurality of second impedances between the second ends and the control circuit, equating a plurality of third impedances between the third ends and the control circuit, and equating a plurality of fourth impedances between the fourth ends and the control circuit.

2. The matrix resistive touch panel according to claim 1, wherein the compensating circuit comprises:

a plurality of first conductive wires electrically connected to the control circuit and the first ends, wherein the first impedances of the first conductive wires are equal;

a plurality of second conductive wires electrically connected to the control circuit and the second ends, wherein the second impedances of the second conductive wires are equal;

a plurality of third conductive wires electrically connected to the control circuit and the third ends, wherein the third impedances of the third conductive wires are equal; and

a plurality of fourth conductive wires electrically connected to the control circuit and the fourth ends, wherein the fourth impedances of the fourth conductive wires are equal.

3. The matrix resistive touch panel according to claim 2, wherein the first conductive wires have different lengths and different cross-section areas, the second conductive wires have different lengths and different cross-section areas, the third conductive wires have different lengths and different cross-section areas, and the fourth conductive wires have different lengths and different cross-section areas.

4. The matrix resistive touch panel according to claim 1, further comprising a plurality of conductive wires for electrically connecting the compensating circuit to the first ends, the second ends, the third ends and the fourth ends, wherein the compensating circuit comprises:

a plurality of first voltage-drop elements electrically connected to the conductive wires and the control circuit, and the first impedances formed by the first voltage-drop elements and the conductive wires connected thereto are equal;

a plurality of second voltage-drop elements electrically connected to the conductive wires and the control circuit, and the second impedances formed by the second voltage-drop elements and the conductive wires connected thereto are equal;

a plurality of third voltage-drop elements electrically connected to the conductive wires and the control circuit, and the third impedances formed by the third voltage-drop elements and the conductive wires connected thereto are equal; and

a plurality of fourth voltage-drop elements, electrically connected to the conductive wires and the control circuit, and the fourth impedances formed by the fourth voltage-drop elements and the conductive wires connected thereto are equal.

5. The matrix resistive touch panel according to claim 4, wherein the cross-section areas of the conductive wires are equal.

6. The matrix resistive touch panel according to claim 4, wherein each of the first voltage-drop elements, each of the second voltage-drop elements, each of the third voltage-drop elements and each of the fourth voltage-drop elements are a resistive element.

7. The matrix resistive touch panel according to claim 4, further comprising a circuit board, wherein the first voltage-drop elements, the second voltage-drop elements, the third voltage-drop elements and the fourth voltage-drop elements are disposed on the circuit board.

8. The matrix resistive touch panel according to claim 7, wherein the circuit board is a flexible circuit board.

9. The matrix resistive touch panel according to claim 7, wherein the control circuit is disposed on the circuit board.

10. The matrix resistive touch panel according to claim 1, further comprising an integrated circuit, wherein the control circuit and the compensating circuit are integrated in the integrated circuit.

11. A design method of a matrix resistive touch panel, comprising:

providing a sensing electrode configuration of a matrix resistive touch panel, wherein the sensing electrode configuration comprises a plurality of first sensing electrodes and a plurality of second sensing electrodes, each first sensing electrode has a first end and a second end, and each second sensing electrode has a third end and a fourth end;

estimating a plurality of first impedances between the first ends and a plurality of first conductive wires in a control end of the matrix resistive touch panel, a plurality of second impedances between the second ends and a plurality of second conductive wires in the control end, a plurality of third impedances between the third ends and a plurality of third conductive wires in the control end, and a plurality of fourth impedances between the fourth ends and a plurality of fourth conductive wires in the control end;

calculating a plurality of compensating impedances of the first impedances, the second impedances, the third impedances and the fourth impedances according to impedance differences of the first impedances, the second impedances, the third impedances and the fourth impedances; and

correspondingly adjusting the first impedances, the second impedances, the third impedances and the fourth impedances through the compensating impedances for equating the first impedances between the first ends and the control end, equating the second impedances between the second end and the control end, equating the third impedances between the third end and the control end, and equating the fourth impedances between the fourth end and the control end.

12. The design method according to claim 11, wherein the step of adjusting the first impedances, the second impedances, the third impedances and the fourth impedances comprises:

correspondingly adjusting the length and the cross-section area of respective of the first conductive wires, the second conductive wires, the third conductive wires and the fourth conductive wires according to the compensating impedances.

13. The design method according to claim 11, wherein the step of adjusting the first impedances, the second impedances, the third impedances and the fourth impedances comprises:

lapping the first conductive wires to a first voltage-drop element, lapping the second conductive wires to a second voltage-drop element, lapping the third conductive wires to a third voltage-drop element, and lapping the fourth conductive wires to a fourth voltage-drop element according to the compensating impedances.