Shape adaptable resistive touchpad

• US 7,573,464 B2
• Filed: 07/20/2006
• Issued: 08/11/2009
• Est. Priority Date: 07/20/2006
• Status: Active Grant

• Current Assignee: Interlink Electronics Incorporated
• Original Assignee: Interlink Electronics Incorporated
• Inventors: Errico, Michael, Baker, Jeffrey R., Sanchez, Carlos Solis
• Primary Examiner(s): Kumar; Srilakshmi K
• Application Number:
  US11/489,922
• Publication Number:
  US 20080018609A1
• Time in Patent Office: 1,118 Days
• Field of Search: 200502-517, 345/156, 345173-178
• US Class Current: 345/173
• CPC Class Codes: G06F 3/045 using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact

Abstract

A touchpad includes a first substrate and a second substrate, at least one of which is flexible. A resistor on the first substrate has a narrow shape dividing the first substrate into two regions. A set of conductors in electrical contact with the resistor extend from the resistor into the two regions. A second resistor and at least one second substrate conductor in electrical contact with the second resistor are on the second substrate. This construction allows the touchpad to have an outer shape is not restricted by the need for rectangular coordinates.

Claims

1. A touchpad comprising:

a first substrate having a first surface;

a second substrate having a second surface, the second substrate positioned so that the second surface faces the first surface and the second substrate is spaced apart from the first substrate;

wherein at least one of the first substrate and the second substrate is flexible, whereby a touch to one of the first substrate and the second substrate brings a portion of the first surface into contact with the second surface;

a first resistor on the first surface, the first resistor having a narrow shape dividing the first surface into a first surface first region and a first surface second region;

a first set of conductors on the first surface along the length of the first resistor and extending from the first resistor into the first surface first region and the first surface second region, the first set of conductors in electrical contact with the first resistor and electrically isolated from one another except through the first resistor, whereby if a voltage potential is applied across the length of the first resistor, each of the first set of conductors will be at different potentials from one another;

a second resistor on the second substrate, the second resistor having a narrow shape dividing the second surface into a second surface first region and a second surface second region; and

a second set of conductors along the length of the second resistor and extending from the second resistor into the second surface first region and the second surface second region, the second set of conductors in electrical contact with the second resistor and electrically isolated from one another except through the second resistor, whereby if a voltage potential is applied across the length of the second resistor, each of the second set of conductors will be at different potentials from one another.

2. The touchpad of claim 1 wherein the first resistor is perpendicular to the second resistor.

3. The touchpad of claim 1 wherein at least one of the first resistor and the second resistor is straight.

4. The touchpad of claim 1 wherein at least one of the first resistor and the second resistor is curved.

5. The touchpad of claim 1 further comprising a spacer layer separating the first substrate from the second substrate.

6. The touchpad of claim 1 wherein at least one of the first substrate and the second substrate is non-rectangular.

7. The touchpad of claim 1 wherein at least one of the first surface and the second surface is non-rectangular.

8. The touchpad of claim 1 wherein the first surface first region and the first surface second region are non-resistive.

9. The touchpad of claim 1 wherein the first set of conductors comprises conductive tines extending from the first resistor into the first surface first region and the first surface second region.

10. The touchpad of claim 1 wherein each conductor in the first set of conductors extends substantially perpendicularly from the first resistor.

11. A touchpad for rendering a touched location in Cartesian coordinates comprising:

an insulative bottom surface divided into two bottom regions by a bottom resistor, each of the two bottom regions covered by a set of parallel first thin conductors which are along the length of the bottom resistor and extend from the bottom resistor, wherein the first thin conductors are electrically isolated from one another except through the bottom resistor, whereby if a voltage potential is applied across the length of the bottom resistor, each of the first thin conductors will be at different potentials from one another; and

an insulative top surface above and facing the bottom surface, the top surface divided into two top regions by a top resistor, each of the two top regions covered by a set of parallel second thin conductors which are along the length of the top resistor and extend from the top resistor, the second thin conductors perpendicular to the first thin conductors, wherein the second thin conductors are electrically isolated from one another except through the top resistor, whereby if a voltage potential is applied across the length of the top resistor, each of the second thin conductors will be at different potentials from one another;

wherein at least one of the bottom surface and the top surface is flexible.

12. The touchpad of claim 11 wherein at least one of the top surface and the bottom surface is non-rectangular.

13. The touchpad of claim 11 further comprising a spacer layer separating the top surface and the bottom surface.

14. A touchpad comprising:

an insulative bottom surface divided into two bottom regions by a bottom resistor, each of the two bottom regions covered by a set of first thin conductors which are along the length of the bottom resistor and extend from the bottom resistor, wherein the first thin conductors are electrically isolated from one another except through the bottom resistor, whereby if a voltage potential is applied across the length of the bottom resistor, each of the first thin conductors will be at different potentials from one another; and

an insulative top surface above and facing the bottom surface, the top surface divided into two top regions by a top resistor, each of the two top regions covered by a set of second thin conductors which are along the length of the top resistor and extend from the top resistor, the second thin conductors orthogonal to the first thin conductors, wherein the second thin conductors are electrically isolated from one another except through the top resistor, whereby if a voltage potential is applied across the length of the top resistor, each of the second thin conductors will be at different potentials from one another;

wherein at least one of the bottom surface and the top surface is flexible.

15. The touchpad of claim 14 wherein at least one of the top surface and the bottom surface is non-rectangular.

16. The touchpad of claim 14 further comprising a spacer layer separating the top surface and the bottom surface.

17. The touchpad of claim 14 wherein at least one of the top resistor and the bottom resistor is curved.

18. The touchpad of claim 14 wherein at least one of the top resistor and the bottom resistor is straight.