Touch pad with flexible substrate

• US 9,591,764 B2
• Filed: 06/30/2014
• Issued: 03/07/2017
• Est. Priority Date: 06/01/2005
• Status: Active Grant

• Current Assignee: Synaptics Incorporated
• Original Assignee: Synaptics Incorporated
• Inventors: Reynolds, Joseph Kurth, Day, Shawn P.
• Primary Examiner(s): POLO, GUSTAVO D
• Application Number:
  US14/320,034
• Publication Number:
  US 20140375908A1
• Time in Patent Office: 981 Days
• Field of Search: 345/174
• US Class Current: 1/1
• CPC Class Codes: G06F 2203/04102 Flexible digitiser, i.e. constructional details for allowing the whole digitising part of a device to be flexed or rolled like a sheet of paper
• 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 3/03547 Touch pads, in which fingers can move on a surface
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/04164 Connections between sensors and controllers, e.g. routing lines between electrodes and connection pads
• CPC Class Codes: G06F 3/044 by capacitive means
• 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: H03K 17/962 Capacitive touch switches
• CPC Class Codes: H03K 2217/960765 Details of shielding arrangements
• CPC Class Codes: H05K 1/0201 Thermal arrangements, e.g. for cooling, heating or preventing overheating
• CPC Class Codes: H05K 1/0218 by printed shielding conductors, ground planes or power plane H05K1/0236 takes precedence
• CPC Class Codes: H05K 1/0274 Optical details, e.g. printed circuits comprising integral optical means H05K1/0269 takes precedence; coupling light guides with opto-electronic components G02B6/42
• CPC Class Codes: H05K 1/144 Stacked arrangements of planar printed circuit boards
• CPC Class Codes: H05K 1/189 characterised by the use of a flexible or folded printed circuit H05K3/326 takes precedence
• CPC Class Codes: H05K 2201/041 Stacked PCBs, i.e. having neither an empty space nor mounted components in between
• CPC Class Codes: H05K 2201/10128 Display
• CPC Class Codes: H05K 2201/10151 Sensor

Abstract

A touch sensor device is provided that uses a flexible circuit substrate to provide an improved input device. Specifically, the present invention uses a touch sensor controller affixed to the flexible circuit substrate, which is coupled to a sensor component to provide a flexible, reliable and cost effective touch sensor suitable for a wide variety of applications. In one embodiment the touch sensor uses a flexible circuit substrate that provides relatively high temperature resistance. This allows the touch sensor controller to be affixed using reliable techniques, such as various types of soldering. The sensor component can comprise a relatively low-temperature-resistant substrate that can provide a cost effective solution. Taken together, this embodiment of the touch sensor provides reliability and flexibility at relatively low cost.

Claims

1. A sensor device comprising:

a flexible circuit substrate that is dimensionally stable up to a first temperature;

a first plurality of conductive pads disposed on the flexible circuit substrate;

a touch controller affixed to the flexible circuit substrate and coupled to the first plurality of conductive pads via a first plurality of conductors;

a flexible sensor substrate that is dimensionally stable up to a second temperature that is lower than the first temperature, wherein the flexible sensor substrate is not dimensionally stable at the first temperature;

a second plurality of conductive pads disposed on the flexible sensor substrate, wherein at least one of the first plurality of conductive pads is coupled to at least one of the second plurality of conductive pads; and

a first plurality of capacitive sensing elements disposed on the flexible sensor substrate and coupled to the second plurality of conductive pads via a second plurality of conductors.

2. The sensor device of claim 1, wherein the flexible sensor substrate is transparent.

3. The sensor device of claim 1, wherein the first temperature is high enough to thermally bond the touch controller to the flexible circuit substrate without degradation to the flexible circuit substrate.

4. The sensor device of claim 1, further comprising:

a second flexible sensor substrate that is dimensionally stable up to the second temperature, wherein the second flexible sensor substrate is not dimensionally stable at the first temperature;

a third plurality of conductive pads disposed on the second flexible sensor substrate, wherein a second at least one of first plurality of conductive pads is coupled to at least one of the third plurality of conductive pads; and

a second plurality of capacitive sensing elements disposed on the second flexible sensor substrate and coupled to the third plurality of conductive pads via a third plurality of conductors.

5. The sensor device of claim 1, further comprising a second plurality of sensing elements disposed on the flexible sensor substrate and coupled to the second plurality of conductive pads, wherein the first plurality of capacitive sensing elements and the second plurality of sensing elements are disposed on a same side of the flexible sensor substrate.

6. The sensor device of claim 1, further comprising a second plurality of sensing elements disposed on the flexible sensor substrate, wherein the first plurality of capacitive sensing elements and the second plurality of sensing elements are disposed on different sides of the flexible sensor substrate.

7. A touch sensor device comprising:

a flexible circuit substrate that is dimensionally stable up to a first temperature, the flexible circuit substrate comprising a first plurality of conductive pads and a first plurality of conductors coupled to the first plurality of conductive pads;

a touch controller affixed to the flexible circuit substrate and coupled to the first plurality of conductors; and

a sensor component comprising;

a transparent flexible sensor substrate that is dimensionally stable up to a second temperature that is lower than the first temperature;

a second plurality of conductive pads disposed on the transparent flexible sensor substrate, wherein the second plurality of conductive pads are coupled to the first plurality of conductive pads; and

a first plurality of transparent sensing elements disposed on the transparent flexible sensor substrate and coupled to the second plurality of conductive pads via a second plurality of conductors.

8. The touch sensor device of claim 7, wherein the sensor component further comprises a second transparent flexible sensor substrate that is dimensionally stable up the second temperature and a second plurality of transparent sensing elements disposed on the second transparent flexible sensor substrate.

9. The touch sensor device of claim 7, wherein the sensor component further comprises a second plurality of transparent sensing elements disposed on the transparent flexible sensor substrate, wherein the first plurality of transparent sensing elements and the second plurality of sensing elements are disposed a same side of the transparent flexible sensor substrate.

10. The touch sensor device of claim 7, wherein the sensor component further comprises a second plurality of transparent sensing elements disposed on the transparent flexible sensor substrate, wherein the first plurality of transparent sensing elements and the second plurality of sensing elements are disposed on different sides of the transparent flexible sensor substrate.

11. The touch sensor device of claim 7, wherein the touch controller is configured to receive electrical signals from at least one of the first plurality of transparent sensing elements, and wherein the touch controller is configured to process the electrical signals.

12. The touch sensor device of claim 7, wherein the touch controller is configured to receive electrical signals from at least one of the first plurality of transparent sensing elements, and wherein the touch controller is configured to pass the electrical signals to an electronic system, wherein the electronic system is configured to process the electrical signals.

13. The touch sensor device of claim 7, wherein the first temperature is high enough to thermally bond the touch sensor controller to the flexible circuit substrate without degradation to the flexible circuit substrate.

14. The touch sensor device of claim 7, further comprising a conductive shield.

15. The touch sensor device of claim 7, wherein the flexible circuit substrate comprises a tail portion.

16. The touch sensor device of claim 7, wherein the first plurality of conductors comprises a first conductor pitch and the second plurality of conductors comprises a second conductor pitch, wherein the first conductor pitch is not equal to the second conductor pitch.

17. The touch sensor device of claim 7, wherein the touch sensor is configured to detect a position of at least one object.

18. The touch sensor device of claim 17, wherein the at least one object comprises at least one of a finger, pointer and a stylus.

19. The touch sensor device of claim 7, wherein the flexible circuit substrate has a first thickness and the transparent flexible sensor substrate has a second thickness different from the first thickness.

20. An input device comprising:

a flexible circuit substrate dimensionally stable up to a first temperature, wherein the first temperature allows thermal bonding to the flexible circuit substrate without significant thermally induced degradation;

a first at least one conductive pad disposed on the flexible circuit substrate;

a touch controller affixed to the flexible circuit substrate and coupled to the first at least one conductive pad via at least one conductor;

a transparent sensor substrate that is dimensionally stable up to a second temperature that is lower than the first temperature, wherein the transparent sensor substrate is not dimensionally stable above the second temperature;

a second at least one conductive pad disposed on the transparent sensor substrate, wherein the second at least one conductive pad is coupled to the first at least one conductive pad; and

at least one conductive sensing element disposed on the transparent sensor substrate, wherein the second at least one conductive pad is coupled to the at least one conductive sensing element, and wherein the touch controller is configured to receive electrical signals from the at least one conductive sensing element to detect a position of at least one object in a sensing region of the input device.

21. The input device of claim 20, further comprising:

a second transparent sensor substrate that is dimensionally stable up to the second temperature, wherein the second transparent sensor substrate is not dimensionally stable above the second temperature; and

a second at least one conductive sensing element disposed on the second transparent substrate, wherein the at least one conductive sensing element is along a first direction and the second at least one conductive sensing element is disposed along a second direction different from the first direction.

22. The input device of claim 20, further comprising a second at least one conductive sensing element disposed on the transparent sensor substrate, wherein the second at least one conductive sensing element and the at least one conductive sensing element are disposed on a same side of the transparent sensor substrate.

23. The input device of claim 20, further comprising a second at least one conductive sensing element disposed on the transparent sensor substrate, wherein the second at least one conductive sensing element and the at least one conductive sensing element are disposed on different sides of the transparent sensor substrate, and wherein the second at least one conductive sensing element is disposed orthogonal to the at least one conductive sensing element.

24. The input device of claim 20, further comprising a display.

25. A touch screen device comprising:

a flexible circuit substrate dimensionally stable up to a first temperature, wherein the first temperature allows thermal bonding to the flexible circuit substrate without significant thermally induced degradation;

a first plurality of conductive pads disposed on the flexible circuit substrate;

a first plurality of conductors coupled to the first plurality of conductive pads;

a touch controller affixed to the flexible circuit substrate and coupled to the first plurality of conductors; and

a sensor component comprising;

a flexible transparent sensor substrate that is dimensionally stable up to a second temperature that is lower than the first temperature, wherein the flexible transparent sensor substrate is not dimensionally stable at the first temperature;

a second plurality of conductive pads coupled the first plurality of conductive pads and disposed on the flexible transparent sensor substrate;

a second plurality of conductors disposed on the flexible transparent sensor substrate and coupled to the second plurality of conductive pads;

a first plurality of transparent capacitive sensing elements disposed on the flexible transparent sensor substrate, wherein the first plurality of transparent capacitive sensing elements are coupled the second plurality of conductors and wherein the first plurality of transparent capacitive sensing elements are aligned along a first direction; and

a second plurality of transparent capacitive sensing elements aligned along a second direction, wherein the first direction differs from the second direction, wherein the touch controller is configured to receive electrical signals from the first plurality of transparent capacitive sensing elements to determine a position of an object in a sensing region of the touch screen device based on detected changes in capacitance.