Capacitive sensing devices

• US 20080297174A1
• Filed: 05/31/2007
• Published: 12/04/2008
• Est. Priority Date: 05/31/2007
• Status: Abandoned Application

• Current Assignee: Synaptics Incorporated
• Original Assignee: Synaptics Incorporated
• Inventors: Narasimhan, Sarangan, Ye, Leonard
• Application Number:
  US11/809,566
• Publication Number:
  US 20080297174A1
• Time in Patent Office: Days
• US Class Current: 324/663
• 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

A capacitive sensing device comprises a set of sensing elements disposed in a two-dimensional arrangement. The two-dimensional arrangement is comprised of full elements and partial elements. A plurality of the partial elements are proximate at least one edge of the two-dimensional arrangement. Additionally, a partial element of the partial elements is smaller in element area than a full element of the full elements. An edge electrode trace of the capacitive sensing device is comprised of a selectively coupled plurality of the partial elements. The selectively coupled plurality of the partial elements resides proximate a first edge of the two-dimensional arrangement.

Claims

1. A capacitive sensing device comprising:

a set of sensing elements disposed in a two-dimensional arrangement comprised of full elements and partial elements, wherein a plurality of said partial elements are proximate at least one edge of said two-dimensional arrangement, and wherein any partial element of said partial elements is smaller in element area than any full element of said full elements; and

an edge electrode trace comprised of a selectively coupled plurality of said partial elements, said selectively coupled plurality of said partial elements residing proximate a first edge of said two-dimensional arrangement.

2. The capacitive sensing device of claim 1, further comprising:

at least one electrode trace comprised of a selectively coupled plurality of said full elements and oriented substantially parallel to said edge electrode trace.

3. The capacitive sensing device of claim 1, further comprising:

at least one electrode trace comprised of a selectively coupled plurality of said full elements and oriented on an axis divergent from said edge electrode trace.

4. The capacitive sensing device of claim 1, further comprising:

a plurality of additional electrode traces, wherein an electrode trace of said plurality of additional electrode traces is comprised of a selectively coupled plurality of said full elements.

5. The capacitive sensing device of claim 4, wherein said edge electrode trace and said plurality of additional electrode traces are configured to detect a two-dimensional position of an object proximate to said capacitive sensing device.

6. The capacitive sensing device of claim 1, and wherein said full elements are substantially uniform in element area, and wherein any partial element of said partial elements comprises an element area of approximately 50% of an element area of a full element of said full elements.

7. The capacitive sensing device of claim 1, further comprising:

a second edge electrode comprised of a selectively coupled second plurality of said partial elements, said second plurality of said partial elements residing proximate a second edge of said two-dimensional arrangement.

8. The capacitive sensing device of claim 7, wherein said second plurality of said partial elements is separate from said plurality of said partial elements residing proximate said first edge.

9. The capacitive sensing device of claim 7, wherein said first edge and said second edge are adjacent edges.

10. The capacitive sensing device of claim 7, wherein said first edge and said second edge are opposite edges.

11. The capacitive sensing device of claim 7, further comprising:

a third edge electrode comprised of a selectively coupled third plurality of said partial elements, said third plurality of said partial elements residing proximate a third edge of said two-dimensional arrangement.

12. The capacitive sensing device of claim 11, wherein said third plurality of said partial elements is separate from both said second plurality of said partial elements and said plurality of said partial elements residing proximate said first edge.

13. The capacitive sensing device of claim 11, further comprising:

a fourth edge electrode comprised of a selectively coupled fourth plurality of said partial elements, said fourth plurality of said partial elements residing proximate a fourth edge of said two-dimensional arrangement.

14. The capacitive sensing device of claim 13, wherein said fourth plurality of said partial elements is separate from said third plurality of said partial elements, second plurality of said partial elements, and said plurality of said partial elements residing proximate said first edge.

15. The capacitive sensing device of claim 1, wherein said set of sensing elements is formed of a substantially transparent material.

16. The capacitive sensing device of claim 1, further comprising:

a guard layer.

17. The capacitive sensing device of claim 1, further comprising:

a flexible substrate upon which said two-dimensional arrangement is disposed.

18. The capacitive sensing device of claim 1, wherein said capacitive sensing device is configured as a two-dimensional object sensing input for an electronic device.

19. The capacitive sensing device of claim 18, further comprising:

a coupling to an electronic device selected from the list of electronic devices consisting of;

a telephone, a computer, a media player, a personal digital assistant, a handheld multi-media device, a keyboard, and a remote control.

20. A method of edge electrode trace formation in a two-dimensional capacitive sensing device comprised of full elements and partial elements which are smaller in element size than said full elements, said method comprising:

identifying a plurality of said partial elements residing proximate a first edge of said two-dimensional capacitive sensing device; and

selectively coupling said plurality of partial elements to form an electrode trace of said two-dimensional capacitive sensing device.

21. The method as recited in claim 20, further comprising:

identifying a second plurality of said partial elements residing proximate a second edge of said two-dimensional capacitive sensing device; and

selectively coupling said second plurality of partial elements to form a second electrode trace of said two-dimensional capacitive sensing device.

22. The method as recited in claim 21, wherein said identifying a second plurality of partial elements residing proximate a second edge of said two-dimensional capacitive sensing device comprises:

identifying said second plurality of said partial elements residing proximate an adjacent edge to said first edge.

23. The method as recited in claim 21, wherein said identifying a second plurality of partial elements residing proximate a second edge of said two-dimensional capacitive sensing device comprises:

identifying said second plurality of said partial elements residing proximate an opposing edge to said first edge.

24. The method as recited in claim 21, further comprising:

identifying a third plurality of said partial elements residing proximate a third edge of said two-dimensional capacitive sensing device; and

selectively coupling said third plurality of said partial elements to form a third electrode trace of said two-dimensional capacitive sensing device.

25. The method as recited in claim 24, further comprising:

identifying a fourth plurality of said partial elements residing proximate a fourth edge of said two-dimensional capacitive sensing device; and

selectively coupling said fourth plurality of said partial elements to form a fourth electrode trace of said two-dimensional capacitive sensing device.

26. The method as recited in claim 20, further comprising:

forming at least one electrode trace to include a full element of said full elements.