Capacitive sensor array with pattern variation

• US 8,988,086 B1
• Filed: 12/28/2011
• Issued: 03/24/2015
• Est. Priority Date: 08/10/2011
• Status: Active Grant

• Current Assignee: Monterey Research, LLC (Vector Capital Corporation)
• Original Assignee: Cypress Semiconductor Corporation (Infineon Technologies AG)
• Inventors: Wilson, Cole, Peterson, Jon
• Primary Examiner(s): TANG, MINH NHUT
• Application Number:
  US13/338,665
• Time in Patent Office: 1,182 Days
• US Class Current: 324/679
• CPC Class Codes: G06F 2203/04103 Manufacturing, i.e. details related to manufacturing processes specially suited for touch sensitive devices
• CPC Class Codes: G06F 2203/04107 Shielding in digitiser, i.e. guard or shielding arrangements, mostly for capacitive touchscreens, e.g. driven shields, driven grounds
• CPC Class Codes: G06F 3/0416 Control or interface arrangements specially adapted for digitisers
• CPC Class Codes: G06F 3/04186 Touch location disambiguation
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• 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
• CPC Class Codes: G06F 3/0448 Details of the electrode shape, e.g. for enhancing the detection of touches, for generating specific electric field shapes, for enhancing display quality
• CPC Class Codes: H03K 2217/960775 Emitter-receiver or "fringe" type detection, i.e. one or more field emitting electrodes and corresponding one or more receiving electrodes

Abstract

Embodiments described herein provide capacitive sensor arrays. The capacitive sensor arrays include a plurality of column sensor elements arranged in a plurality of columns and a plurality of row sensor elements arranged in a plurality of rows. The plurality of rows and the plurality of columns are arranged such that each of the row sensor elements is at least partially within a gap between adjacent ones of the column sensor elements. A capacitance between a first portion of one of the columns and an adjacent first portion of one of the rows is greater than a capacitance between a second portion of one of the columns and an adjacent second portion of one of the rows.

Claims

1. A capacitive sensor array comprising:

a plurality of column sensor elements arranged in a plurality of columns; and

a plurality of row sensor elements arranged in a plurality of rows, wherein the plurality of rows and the plurality of columns are arranged such that each of the row sensor elements is at least partially within a gap between adjacent ones of the column sensor elements, wherein a capacitance between a first column sensor element and an adjacent first row sensor element is greater than a capacitance between the first column sensor element and an adjacent second row sensor element.

2. The capacitive sensor array of claim 1, wherein a first edge of the first column sensor element, which is adjacent to the adjacent first row sensor element, has a first length that is greater than a second length of a second edge of the first column sensor element, which is adjacent to the adjacent second row sensor element.

3. The capacitive sensor array of claim 2, wherein a first edge of the adjacent first row sensor element, which is adjacent to the first edge of the first column sensor element, has a first length that is greater than a second length of a first edge of the adjacent second row sensor element, which is adjacent to the second edge of the first column sensor element.

4. The capacitive sensor array of claim 3, wherein the first edge of the first column sensor element, the first edge of the adjacent first row sensor element, and the first edge of the adjacent second row sensor element each have a sawtooth shape.

5. The capacitive sensor array of claim 1, wherein a first distance between the first edge of the first column sensor element and the first edge of the adjacent first row sensor element is less than a distance between the second edge of the first column sensor element and the first edge of the adjacent second row sensor element.

6. The capacitive sensor array of claim 1, wherein a distance between one of the column sensor elements and an adjacent one of the row sensor elements varies between adjacent edges of the one of the column sensor elements and the adjacent one of the row sensor elements.

7. The capacitive sensor array of claim 1, wherein the plurality of column sensor elements and the plurality of row sensor elements are coplanar.

8. The capacitive sensor array of claim 7, wherein at least two of the plurality of column sensor elements and the plurality of row sensor elements are substantially diamond-shaped.

9. The capacitive sensor array of claim 8, wherein the plurality of column sensor elements and the plurality of row sensor elements comprise indium tin oxide (ITO).

10. A mutual capacitance sensor array comprising:

a plurality of transmitter electrodes; and

a plurality of receiver electrodes, wherein the plurality of receiver electrodes are arranged such that each of the plurality of receiver electrodes is at least partially within a space between adjacent ones of the plurality of transmitter electrodes, and wherein the plurality of transmitter electrodes and the plurality of receiver electrodes are configured such that a row-column capacitance between the plurality of transmitter electrodes and adjacent ones of the plurality of receiver electrodes varies across different regions of the mutual capacitance sensor array, wherein a capacitive coupling between a first transmitter electrode and an adjacent first receiver electrode is greater than a capacitive coupling between the first transmitter electrode and an adjacent second receiver electrode.

11. The mutual capacitance sensor array of claim 10, wherein a length of the edges of the plurality of transmitter electrodes and a length of the edges of the plurality of receiver electrodes varies across different regions of the mutual capacitance sensor array.

12. The mutual capacitance sensor array of claim 10, wherein a row-column capacitance between the plurality of transmitter electrodes and adjacent ones of the plurality of receiver electrodes on a first region of the mutual capacitance sensor array is greater than a row-column capacitance between the plurality of transmitter electrodes and adjacent ones of the plurality of receiver electrodes on a second region of the mutual capacitance sensor array.

13. The mutual capacitance sensor array of claim 12, wherein lengths of the edges of the plurality of transmitter electrodes and lengths of the edges of the plurality of receiver electrodes on the first region of the mutual capacitance sensor array are greater than respective lengths of the edges of the plurality of transmitter electrodes and lengths of the edges of the plurality of receiver electrodes on the second region of the mutual capacitance sensor array.

14. The mutual capacitance sensor array of claim 13, wherein the edges of the plurality of transmitter electrodes and the edges of the of the plurality of receiver electrodes on the first region of the mutual capacitance sensor array have a sawtooth shape.

15. A method for operating a capacitive sensing device, the method comprising:

providing a capacitive sensor array comprising

a plurality of column sensor elements arranged in a plurality of columns, and

a plurality of row sensor elements arranged in a plurality of rows, wherein the plurality of rows overlap the plurality of columns such that each of the row sensor elements is at least partially within a gap between adjacent ones of the column sensor elements,

wherein a capacitive coupling between a first column sensor element and an adjacent first row sensor element is greater than a capacitive coupling between the first column sensor element and an adjacent second row sensor element;

detecting a change in a row-column capacitance associated with the first column sensor element, the adjacent first row sensor element, and the adjacent second row sensor element; and

determining a proximity of an object to the capacitive sensing device based on the detected change.

16. The method of claim 15, wherein a first edge of the first column sensor element, which is adjacent to the adjacent first row sensor element, has a length that is greater than a length of a second edge of the first column sensor element, which is adjacent to the adjacent second row sensor element, and

wherein an edge of the adjacent first row sensor element, which is adjacent to the first edge of the first column sensor element, has a length that is greater than a length of an edge of the adjacent second row sensor element, which is adjacent to the second edge of the first column sensor element.

17. The method of claim 15, wherein a distance between the first edge of the first column sensor element and the edge of the adjacent first row element is less than a distance between the second edge of the first column sensor element and the edge of the adjacent second row element.

18. The method of claim 15, wherein the plurality of column sensor elements and the plurality of row sensor elements are coplanar.

19. The method of claim 15, wherein the plurality of column sensor elements and the plurality of row sensor elements comprise indium tin oxide (ITO).