RESISTIVE TOUCH PANEL AND METHOD FOR DETECTING TOUCH POINT TYPE

• US 20100328263A1
• Filed: 06/24/2010
• Published: 12/30/2010
• Est. Priority Date: 06/29/2009
• Status: Abandoned Application

• Current Assignee: ASUSTek Computer, Inc.
• Original Assignee: ASUSTek Computer, Inc.
• Inventors: LIN, HUNG-YI
• Application Number:
  US12/822,585
• Publication Number:
  US 20100328263A1
• Time in Patent Office: Days
• US Class Current: 345/174
• CPC Class Codes: G06F 3/04166 Details of scanning methods, e.g. sampling time, grouping of sub areas or time sharing with display driving Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally G06F3/04184
• CPC Class Codes: G06F 3/045 using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact

Abstract

The invention discloses a method for detecting touch point type in a resistive touch panel. The method includes the steps of: connecting the first electrode to a voltage source and connecting the fourth electrode to the ground end when it is determined that a touch point is generated on the first detecting area, thereby making the second electrode generate a first voltage and the third electrode generate a second voltage; determining that the touch point is the first-type touch point when the difference between the first voltage and the second voltage is larger than a threshold value; and determining that the touch point is the second-type touch point when the difference between the first voltage and the second voltage is smaller than a first threshold value.

Claims

1. A method for detecting a touch point type of a resistive touch panel, wherein the resistive touch panel includes multiple detecting areas, and a first detecting area in the detecting areas is defined by a first electrode, a second electrode, a third electrode and a fourth electrode, the first electrode and the second electrode belong to first-direction electrode, and the third electrode and the fourth electrode belong to second-direction electrodes, the method for detecting the touch point type comprising the steps of:

connecting the first electrode to a voltage source and connecting the fourth electrode to a ground end when a touch point is generated on the first detecting area, thereby making the second electrode generate a first voltage and the third electrode generate a second voltage; and

determining that the touch point is a first-type touch point when the difference between the first voltage and the second voltage is larger than a first threshold value, and determining that the touch point is a second-type touch point when the difference between the first voltage and the second voltage is smaller than the first threshold value.

2. The method for detecting the touch point type according to claim 1, wherein the first-type touch point is a small-area touch point, and the second-type touch point is a large-area touch point.

3. The method for detecting the touch point type according to claim 1, wherein the first-type touch point is a stylus touch point, a penpoint touch point or a sharp object touch point, and the second-type touch point is a finger touch point or a palm touch point.

4. The method for detecting the touch point type according to claim 1, wherein the first-direction electrodes are along an X-direction, the first electrode and the second electrode correspond to each other, the second-direction electrodes are along a Y-direction, and the third electrode and the fourth electrode correspond to each other.

5. A method for detecting a touch point type of a resistive touch panel, wherein the resistive touch panel includes multiple detecting areas, and a first detecting area in the detecting areas is defined by a first electrode, a second electrode, a third electrode and a fourth electrode, the first electrode and the second electrode belong to first-direction electrodes, and the third electrode and the fourth electrode belong to second-direction electrodes, the method for detecting the touch point type comprising the steps of:

connecting the third electrode to a voltage source and connecting the fourth electrode to a ground end when a touch point is generated on the first detecting area, thereby obtaining a contact voltage of the touch point and a current value passing through the touch point;

switching the voltage source to the first electrode from the third electrode and connecting the fourth electrode to the ground end to make the second electrode generate a first voltage and the third electrode generate a second voltage;

calculating a contact resistance according to the contact voltage, the current value, the first voltage and the second voltage; and

determining that the touch point is a first-type touch point when the contact resistance is larger than a preset contact resistance, and determining that the touch point is a second-type touch point when the contact resistance is smaller than the preset contact resistance.

6. The method for detecting the touch point type according to claim 5, wherein the first-type touch point is a small-area touch point, and the second-type touch point is a large-area touch point.

7. The method for detecting the touch point type according to claim 5, wherein the first-type touch point is a stylus touch point, a penpoint touch point or a sharp object touch point, and the second-type touch point is a finger touch point or a palm touch point.

8. The method for detecting the touch point type according to claim 5, wherein the first-direction electrodes are along an X-direction, the first electrode and the second electrode correspond to each other, the second-direction electrodes are along a Y-direction, and the third electrode and the fourth electrode correspond to each other.

9. A method for detecting a touch point type of a resistive touch panel, wherein the resistive touch panel includes multiple detecting areas, and a first detecting area in the detecting areas is defined by a first electrode, a second electrode, a third electrode and a fourth electrode, the first electrode corresponds to the second electrode, the third electrode corresponds to the fourth electrode, the method for detecting the touch point type comprising the steps of:

connecting the first electrode to a voltage source and connecting the second electrode to a ground end when a touch point is generated on the first detecting area, thereby making the third electrode generate a third voltage and the fourth electrode generate a fourth voltage; and

determining that the touch point is a first-type touch point when the difference between the third voltage and the fourth voltage is smaller than a threshold value, and determining that the touch point is a second-type touch point when the difference between the third voltage and the fourth voltage is larger than the threshold value.

10. The method for detecting the touch point type according to claim 9, wherein the first-type touch point is a small-area touch point, and the second-type touch point is a large-area touch point.

11. The method for detecting the touch point type according to claim 9, wherein the first-type touch point is a stylus touch point, a penpoint touch point or a sharp object touch point, and the second-type touch point is a finger touch point or a palm touch point.

12. The method for detecting the touch point type according to claim 9, wherein the first-direction electrodes are along an X-direction, the first electrode and the second electrode correspond to each other, the second-direction electrodes are along a Y-direction, and the third electrode and the fourth electrode correspond to each other.

13. A resistive touch panel comprising:

a first-direction first electrode group including m electrodes;

a first-direction second electrode group including m electrodes;

a second-direction first electrode group including n electrodes;

a second-direction second electrode group including n electrodes;

wherein the 2m+2n electrodes divide the resistive touch panel into m×

n detecting areas;

a multiplex switching circuit connected to each of the 2m+2n electrodes; and

a control circuit, determining that a touch point is a first-type touch point or a second-type touch point when the touch point is generated at a first detecting area in the detecting areas.

14. The resistive touch panel according to claim 13, wherein the first detecting area is defined by a first electrode, a second electrode, a third electrode and a fourth electrode, the first electrode belongs to the first-direction first electrode group, the second electrode belongs to the first-direction second electrode group, the third electrode belongs to the second-direction first electrode group, and the fourth electrode belongs to the second-direction second electrode group.

15. The resistive touch panel according to claim 13, wherein when a touch point is generated on the first detecting area, the first electrode is connected to a voltage source and the fourth electrode is connected to the ground end to make the second electrode generate a first voltage and the third electrode generate a second voltage;

when the difference between the first voltage and the second voltage is larger than a threshold value, it is determined that the touch point is the first-type touch point; and

when the difference between the first voltage and the second voltage is smaller than the threshold value, it is determined that the touch point is the second-type touch point.

16. The resistive touch panel according to claim 13, wherein when it is determined that a touch point is generated on the first detecting area, the first electrode is connected to a voltage source and the second electrode is connected to the ground end to make the third electrode generate a third voltage and the fourth electrode generate a fourth voltage;

and when the difference between the third voltage and the fourth voltage is smaller than a threshold value, it is determined that the touch point is the first-type touch point; and

when the difference between the third voltage and the fourth voltage is larger than the threshold value, it is determined that the touch point is the second-type touch point.

17. The resistive touch panel according to claim 13, wherein the first-type touch point is a small-area touch point, and the second-type touch point is a large-area touch point.

18. The resistive touch panel according to claim 13, wherein the first-type touch point is a stylus touch point, a penpoint touch point or a sharp object touch point, and the second-type touch point is a finger touch point or a palm touch point.