Touch panel and multi-touch detecting method thereof

• US 8,400,421 B2
• Filed: 06/29/2010
• Issued: 03/19/2013
• Est. Priority Date: 07/10/2009
• Status: Active Grant

• Current Assignee: InnoLux Corporation
• Original Assignee: Chi Mei Innolux Corporation (InnoLux Corporation)
• Inventors: Shih, Po-Sheng, Chao, Chih-Han, Chen, Po-Yang, Cheng, Chien-Yung
• Primary Examiner(s): HALEY, JOSEPH R
• Application Number:
  US12/825,347
• Publication Number:
  US 20110005844A1
• Time in Patent Office: 994 Days
• Field of Search: None
• US Class Current: 345/174
• CPC Class Codes: G06F 2203/04808 Several contacts: gestures triggering a specific function, e.g. scrolling, zooming, right-click, when the user establishes several contacts with the surface simultaneously; e.g. using several fingers or a combination of fingers and pen
• CPC Class Codes: G06F 3/0416 Control or interface arrangements specially adapted for digitisers
• 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
• CPC Class Codes: G06F 3/04883 for inputting data by handwriting, e.g. gesture or text

Abstract

A multi-touch detecting method is adapted for detecting locations of touched points on a touch panel including first and second conductive films, and includes following steps. First measuring points of the first conductive film distributed along X-axis of a Cartesian plane are scanned, and x-components are determined accordingly. Second measuring points of the second conductive film distributed along Y-axis of the Cartesian plane are scanned, and y-components are determined accordingly. A first voltage is applied to the first conductive film, and A second voltage is applied to at least one of the second measuring points with the location on the Y-axis adjacent to or overlapping one of the y-components. Voltages at the first measuring points with the locations on the X-axis adjacent to or overlapping the x-components are measured sequentially and one of the y-components and one of the x-components are outputted.

Claims

1. A multi-touch detecting method adapted for detecting locations of touched points on a touch panel, the touch panel including first and second conductive films insulated from each other and coupled electrically to each other through touch, the multi-touch detecting method comprising:

scanning first measuring points of the first conductive film distributed along X-axis of a Cartesian plane of the touch panel, and determining x-components of the touched points, based on the response of the first measuring points;

scanning second measuring points of the second conductive film distributed along Y-axis of the Cartesian plane of the touch panel, and determining y-components of the touched points, based on the response of the second measuring points;

applying a first voltage to the first conductive film; and

applying a second voltage different from the first voltage to at least one of the second measuring points with the location on the Y-axis adjacent to or overlapping one of the y-components, measuring sequentially voltages at the first measuring points with the locations on the X-axis adjacent to or overlapping the x-components, in response to the application of the second voltage, and outputting the one of the y-components and one of the x-components, which corresponds to one of the first measuring points at which a local extreme voltage is measured, as the location of a corresponding one of the touched points.

2. The multi-touch detecting method of claim 1, wherein the voltages are measured in such a manner that while each of the first measuring points is measured, the first voltage is applied to the rest of the first measuring points.

3. The multi-touch detecting method of claim 1, further comprising providing the first voltage to at least one of the second measuring points located between two of the second measuring points with the locations on the Y-axis adjacent to or overlapping two adjacent ones of the y-components, respectively.

4. The multi-touch detecting method of claim 1, wherein the second voltage is greater than the first voltage, the local extreme voltage being a local maximal voltage.

5. The multi-touch detecting method of claim 1, wherein the second voltage is smaller than the first voltage, the local extreme voltage being a local minimal voltage.

6. A multi-touch detecting method adapted for detecting locations of touched points on a touch panel, the touch panel including first and second conductive films insulated from each other and coupled electrically to each other through touch, the multi-touch detecting method comprising:

(a) scanning first measuring points of the first conductive film distributed along X-axis of a Cartesian plane of the touch panel, and determining x-components, which correspond to the locations of the touched points, based on the response of the first measuring points;

(b) scanning second measuring points of the second conductive film distributed along Y-axis of the Cartesian plane of the touch panel, and determining y-components, which correspond to the locations of the touched points, based on the response of the second measuring points;

(c) applying a first voltage to the first conductive film;

(d) applying a second voltage different from the first voltage to at least one of the second measuring points with the location on the Y-axis adjacent to or overlapping one of the y-components, and measuring sequentially voltages at the first measuring points with the locations on the X-axis adjacent to or overlapping the x-components, in response to the application of the second voltage;

(e) simultaneously applying the second voltage to the at least one of the second measuring points with the location on the Y-axis adjacent to or overlapping the one of the y-components in step (d), and to at least one of the second measuring points with the location on the Y-axis adjacent to or overlapping another one of the y-components, and measuring sequentially voltages at the first measuring points with the locations on the X-axis adjacent to or overlapping the x-components, in response to the application of the second voltage; and

(f) outputting the one of the y-components and one of the x-components, which corresponds to one of the first measuring points at which a local extreme voltage is measured in step (e), as the location of a corresponding one of the touched points when the voltages measured at the one of the first measuring points in steps (d) and (e) are different.

7. The multi-touch detecting method of claim 6, wherein in steps (d) and (e), the voltages are measured in such a manner that while each of the first measuring points is measured, the first voltage is applied to the rest of the first measuring points.

8. The multi-touch detecting method of claim 6, further comprising:

providing the first voltage to at least one of the second measuring points located between two of the second measuring points with the locations on the Y-axis adjacent to or overlapping two adjacent ones of the y-components, respectively.

9. The multi-touch detecting method of claim 6, wherein the second voltage is greater than the first voltage, in step (f), the local extreme voltage being a local maximal voltage.

10. The multi-touch detecting method of claim 6, wherein the second voltage is smaller than the first voltage, in step (f), the local extreme voltage being a local minimal voltage.

11. A multi-touch detecting method adapted for detecting locations of touched points on a touch panel, the touch panel including first and second conductive films insulated from each other, the first conductive film having a plurality of first measuring points distributed along X-axis of a Cartesian plane of the touch panel, the second conductive film having a plurality of second measuring points distributed along Y-axis of the Cartesian plane of the touch panel, the multi-touch detecting method comprising:

applying a first voltage to the first conductive film;

applying a second voltage different from the first voltage to one of the second measuring points;

measuring sequentially voltages at the first measuring points in response to the application of the second voltage; and

outputting a location based on the one of the second measuring points and one of the first measuring points at which a local extreme voltage is measured.

12. The multi-touch detecting method of claim 11, wherein the voltages are measured in such a manner that while each of the first measuring points is measured, the first voltage is applied to the rest of the first measuring points.

13. The multi-touch detecting method of claim 11, wherein the second voltage is greater than the first voltage, the local extreme voltage being a local maximal voltage.

14. The multi-touch detecting method of claim 11, wherein the second voltage is smaller than the first voltage, the local extreme voltage being a local minimal voltage.

15. A multi-touch detecting method adapted for detecting locations of touched points on a touch panel, the touch panel including first and second conductive films insulated from each other the first conductive film having a plurality of first measuring points distributed along X-axis of a Cartesian plane, the second conductive film having a plurality of second measuring points distributed along Y-axis of the Cartesian plane, the multi-touch detecting method comprising:

(a) applying a first voltage to the first conductive film;

(b) applying a second voltage different from the first voltage to one of the second measuring points, and measuring sequentially voltages at the first measuring points in response to the application of the second voltage;

(c) simultaneously applying the second voltage to the one of the second measuring points in step (b) and to another one of the second measuring points, and measuring sequentially voltages at the first measuring points in response to the application of the second voltage; and

(d) outputting a location based on the another one of the second measuring points and one of the first measuring points at which a local extreme voltage is measured in step (c) when the voltages measured at the one of the first measuring points in steps (b) and (c) are different.