Trace pattern for touch-sensing application

• US 9,405,408 B2
• Filed: 01/18/2011
• Issued: 08/02/2016
• Est. Priority Date: 01/15/2010
• Status: Active Grant

• Current Assignee: Wistron Corporation
• Original Assignee: Creator Technology BV
• Inventors: Peng, Tao, Weng, XiaoPing, Shao, DangDang, Deng, Yingzhu
• Primary Examiner(s): MA, CALVIN
• Application Number:
  US13/008,014
• Publication Number:
  US 20120044193A1
• Time in Patent Office: 2,023 Days
• Field of Search: 345/173, 345/174, 324/658, 324/662
• US Class Current: 1/1
• CPC Class Codes: G06F 2203/04111 Cross over in capacitive digitiser, i.e. details of structures for connecting electrodes of the sensing pattern where the connections cross each other, e.g. bridge structures comprising an insulating layer, or vias through substrate
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes

Abstract

One embodiment of a capacitive sensor array comprises a plurality of row sensor elements including a first row sensor element, a plurality of column sensor elements including a first column sensor element, and a plurality of unit cells, wherein a first unit cell contains an intersection between the first row sensor element and the first column sensor element, and wherein a ratio between 1) a boundary length between the first row sensor element and the first column sensor element within the first unit cell and 2) a perimeter of the first unit cell is greater than √{square root over (2)}/2.

Claims

1. A capacitive sensor array, comprising:

a plurality of row sensor elements including a first row sensor element;

a plurality of column sensor elements including a first column sensor element; and

a plurality of unit cells, wherein each of the plurality of unit cells contains an intersection between one of the plurality of row sensor elements and one of the plurality of column sensor elements, and wherein a first unit cell contains a first intersection between the first row sensor element and the first column sensor element, wherein one of the first row sensor element and the first column sensor element is configured to provide a signal that is based on a mutual capacitance associated with the first unit cell, wherein a ratio between

     1) a boundary length between the first row sensor element and the first column sensor element within the first unit cell and

     2) a perimeter of the first unit cell is greater than √

{square root over (2)}/2, wherein the first column sensor element includes at least a first cutout area which reduce a self capacitance of the first column sensor element, and wherein the first row sensor element includes at least a second cutout area corresponding to the first cutout area, and the second cutout area reduces a self capacitance of the first row sensor element.

2. The capacitive sensor array of claim 1, wherein the boundary length includes points on an edge of the first row sensor element that are within the unit cell and are within a threshold distance from an edge of the first column sensor element.

3. The capacitive sensor array of claim 1, wherein the boundary length includes points on an edge of the first row sensor element from which a straight line can be drawn to an edge of the first column sensor element without first crossing over a portion of the first row sensor element.

4. The capacitive sensor array of claim 1, wherein a trace pattern formed by the first row sensor element and the first column sensor element within the first unit cell is substantially similar to a trace pattern of each of the other unit cells.

5. The capacitive sensor array of claim 1, wherein the width of each unit cell along a first axis is approximately equal to a distance between corresponding intersections along the first axis.

6. The capacitive sensor array of claim 1, wherein the unit cell is defined by a plurality of boundaries, and wherein each of the plurality of boundaries is a common boundary shared with a unit cell of an adjacent intersection.

7. The capacitive sensor array of claim 1, wherein the unit cell contains the first row sensor element and the first column sensor element while excluding all other sensor elements of the plurality of row sensor elements and the plurality of column sensor elements of the capacitive sensor array.

8. A capacitive sensor array, comprising:

a plurality of row sensor elements including a first row sensor element;

a plurality of column sensor elements including a first column sensor element; and

a plurality of unit cells, wherein each of the plurality of unit cells contains an intersection between one of the plurality of row sensor elements and one of the plurality of column sensor elements, and wherein a first unit cell contains a first intersection between the first row sensor element and the first column sensor element, wherein one of the first row sensor element and the first column sensor element is configured to provide a signal that is based on a mutual capacitance associated with the first unit cell, wherein

9. The capacitive sensor array of claim 8, wherein the boundary length includes points on an edge of the first row sensor element that are within the unit cell and are within a threshold distance from an edge of the first column sensor element.

10. The capacitive sensor of claim 8, wherein a trace pattern formed by the first row sensor element and the first column sensor element within the first unit cell is substantially similar to a trace pattern of each of the other unit cells.

11. The capacitive sensor array of claim 8, wherein the unit cell contains the first row sensor element and the first column sensor element while excluding all other sensor elements of the plurality of row sensor elements and the plurality of column sensor elements of the capacitive sensor array.

12. A capacitive touch-sensing system, comprising:

a capacitive sensor array, comprising;

a plurality of row sensor elements including a first row sensor element;

a plurality of column sensor elements including a first column sensor element; and

a plurality of unit cells, wherein each of the plurality of unit cells contains an intersection between one of the plurality of row sensor elements and one of the plurality of column sensor elements, wherein a first unit cell contains a first intersection between the first row sensor element and the first column sensor element, and wherein a ratio between

     1) a boundary length between the first row sensor element and the first column sensor element within the first unit cell and

     2) a perimeter of the first unit cell is greater than √

{square root over (2)}/2, wherein the first column sensor element includes at least a first cutout area which reduce a self capacitance of the first column sensor element, and wherein the first row sensor element includes at least a second cutout area corresponding to the first cutout area, and the second cutout area reduces a self capacitance of the first row sensor element; and

a capacitance sensor coupled with the capacitive sensor array, wherein the capacitance sensor is configured to measure a mutual capacitance for each of the intersections.

13. The capacitive touch-sensing system of claim 12, wherein the capacitance sensor is further configured to calculate at least one centroid position of a contact at the touch-sensing surface based on the measured mutual capacitances.

14. The capacitive touch-sensing system of claim 12, wherein the boundary length includes points on an edge of the first row sensor element that are within the unit cell and are within a threshold distance from an edge of the first column sensor element.

15. A capacitive sensor array, comprising:

a plurality of row sensor elements including a first row sensor element;

a plurality of column sensor elements including a first column sensor element; and

a plurality of unit cells, wherein each of the plurality of unit cells contains an intersection between one of the plurality of row sensor elements and one of the plurality of column sensor elements, and wherein a first unit cell contains a first intersection between the first row sensor element and the first column sensor element, wherein one of the first row sensor element and the first column sensor element is configured to provide a signal that is based on a mutual capacitance associated with the first unit cell, wherein a ratio between

     1) a boundary length between the first row sensor element and the first column sensor element within the first unit cell and

     2) a perimeter of the first unit cell is greater than √

{square root over (2)}/2, wherein the first row sensor element comprises a first main trace and a plurality of first subtraces branching from the first main trace, and wherein the first column sensor element comprises a second main trace and a plurality of second subtraces branching from the second main trace, wherein the second main trace and each of the second subtraces have at least one gap located therebetween, and each of the first subtraces extends into one of the gaps.

16. The capacitive sensor array of claim 15, wherein the first substraces and the second subtraces are arranged alternately along an extension direction of the first main trace.

17. A capacitive sensor array, comprising:

a plurality of row sensor elements including a first row sensor element;

a plurality of column sensor elements including a first column sensor element; and

a plurality of unit cells, wherein each of the plurality of unit cells contains an intersection between one of the plurality of row sensor elements and one of the plurality of column sensor elements, and wherein a first unit cell contains a first intersection between the first row sensor element and the first column sensor element, wherein one of the first row sensor element and the first column sensor element is configured to provide a signal that is based on a mutual capacitance associated with the first unit cell, wherein

18. The capacitive sensor array of claim 17, wherein the first substraces and the second subtraces are arranged alternately along an extension direction of the first main trace.

19. A capacitive touch-sensing system, comprising:

a capacitive sensor array, comprising;

a plurality of row sensor elements including a first row sensor element;

a plurality of column sensor elements including a first column sensor element; and

a plurality of unit cells, wherein each of the plurality of unit cells contains an intersection between one of the plurality of row sensor elements and one of the plurality of column sensor elements, wherein a first unit cell contains a first intersection between the first row sensor element and the first column sensor element, and wherein a ratio between

     1) a boundary length between the first row sensor element and the first column sensor element within the first unit cell and

     2) a perimeter of the first unit cell is greater than √

{square root over (2)}/2, wherein the first row sensor element comprises a first main trace and a plurality of first subtraces branching from the first main trace, and wherein the first column sensor element comprises a second main trace and a plurality of second subtraces branching from the second main trace, wherein the second main trace and each of the second subtraces have at least one gap located therebetween, and each of the first subtraces extends into one of the gaps; and

a capacitance sensor coupled with the capacitive sensor array, wherein the capacitance sensor is configured to measure a mutual capacitance for each of the intersections.

20. The capacitive touch-sensing system of claim 19, wherein the first substraces and the second subtraces are arranged alternately along an extension direction of the first main trace.