Capacitive position sensor

• US 7,986,152 B2
• Filed: 10/05/2010
• Issued: 07/26/2011
• Est. Priority Date: 05/07/2007
• Status: Active Grant

• Current Assignee: Neodrón Limited (Atlantic IP Services Limited)
• Original Assignee: Atmel Corporation (Microchip Technology Incorporated)
• Inventors: Philipp, Harald, Brunet, Samuel, Trend, Matthew, Bowens, Alan
• Primary Examiner(s): Nguyen, Hoai-An D
• Application Number:
  US12/898,153
• Publication Number:
  US 20110022351A1
• Time in Patent Office: 294 Days
• Field of Search: 324/662, 324/661, 324/658, 324/649, 324/688, 324/686, 324/600, 341/33, 345/173
• US Class Current: 324/662
• 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

In one embodiment, a sensor includes a substrate; multiple interconnected sense elements arranged in a first direction on a surface of the substrate; and first interconnected drive elements arranged on a surface of the substrate in the first direction. Each respective one of the first interconnected drive elements are located adjacent to and between respective ones of the sense elements to form first sets of sense and drive elements alternating in the first direction. The sensor also includes second interconnected drive elements arranged on a surface of the substrate in a second direction. Each respective one of the second interconnected drive elements are located between respective ones of the sense elements to form second sets of sense and drive elements alternating in the second direction.

Claims

1. A sensor comprising:

a substrate;

a plurality of interconnected sense elements arranged in a first direction on a surface of the substrate;

a first plurality of interconnected drive elements arranged on a surface of the substrate in the first direction, each respective one of the first plurality of interconnected drive elements being located adjacent to and between respective ones of the plurality of sense elements to form first sets of sense and drive elements alternating in the first direction; and

a second plurality of interconnected drive elements arranged on a surface of the substrate in a second direction, each respective one of the second plurality of interconnected drive elements being located between respective ones of the plurality of sense elements to form second sets of sense and drive elements alternating in the second direction.

2. The sensor of claim 1, wherein the sense elements, the first plurality of drive elements, and the second plurality of drive elements are provided on the first surface of the substrate.

3. The sensor of claim 1, wherein the first plurality of drive elements and the second plurality of drive elements are provided on different surfaces of the substrate.

4. The sensor of claim 1, wherein the sense elements are substantially circular in shape.

5. The sensor of claim 1, wherein the first plurality of drive elements are substantially hexagonal in shape.

6. The sensor of claim 1, wherein each of the plurality of drive elements has at least one edge contoured to be complimentary to at least one of the sense elements.

7. The sensor of claim 1 further comprising a controller, comprising at least one drive unit configured to apply drive signals to the first and second pluralities of drive elements and at least one sense unit, configured to sense signals representing a degree of coupling of the drive signals applied to the first and second plurality of drive elements to the sense electrodes.

8. The sensor of claim 7, wherein the controller further comprises a processing unit configured to calculate a position of an object in one direction from an analysis of the sense signals obtained by applying drive signals to different ones of the first plurality of drive elements and calculate a position of the object in another direction from an analysis of the sense signals obtained by applying drive signals to different ones of the second plurality of drive elements.

9. The sensor of claim 1, wherein the first direction and the second direction are substantially orthogonal.

10. The sensor of claim 9, wherein the first sets of sense and drive elements form columns of alternating sense and drive elements and the second sets of sense of drive elements form rows of alternating sense and drive elements.

11. The sensor of claim 1, wherein the drive elements are formed of a substantially transparent conductive material.

12. The sensor of claim 1, wherein the first plurality of drive elements, the second plurality of drive elements, and the plurality of sense elements are arranged such that the elements do not overlap.

13. An electronic device, comprising:

a housing;

a touch-sensitive sensor disposed within the housing, the touch-sensitive sensor comprising;

a substrate;

a plurality of interconnected sense elements arranged in a first direction on a surface of the substrate;

a first plurality of interconnected drive elements arranged on a surface of the substrate in the first direction, each respective one of the first plurality of interconnected drive elements being located adjacent to and between respective ones of the plurality of sense elements to form first sets of sense and drive elements alternating in the first

direction; and

a second plurality of interconnected drive elements arranged on a surface of the substrate in a second direction, each respective one of the second plurality of interconnected drive elements being located between respective ones of the plurality of

sense elements to form second sets of sense and drive elements alternating in the second direction; and

a controller in communication with the touch-sensitive sensor comprising a drive unit and sense unit, the drive unit configured to apply drive signals to the first and second pluralities of drive elements and a sense unit configured to sense signals representing a degree of coupling of the drive signals applied to the first and second plurality of drive elements to the sense electrodes.

14. The electronic device of claim 13, wherein the first plurality of drive elements and the second plurality of drive elements are provided on different surfaces of the substrate.

15. The electronic device of claim 13, wherein the sense elements are substantially circular in shape.

16. The electronic device of claim 13, wherein the first plurality of drive elements are substantially hexagonal in shape.

17. The electronic device of claim 13, wherein the controller further comprises a processing unit configured to calculate a position of an object in one direction from an analysis of the sense signals obtained by applying drive signals to different ones of the first plurality of drive elements and calculate a position of the object in another direction from an analysis of the sense signals obtained by applying drive signals to different ones of the second plurality of drive elements.

18. The electronic device of claim 13, wherein the first direction and the second direction are substantially orthogonal.

19. The electronic device of claim 13, wherein the drive elements are formed of a substantially transparent conductive material.

20. The electronic device of claim 13, wherein the first plurality of drive elements, the second plurality of drive elements, and the plurality of sense elements are arranged such that the elements do not overlap.