TOUCH SCREEN STACK-UP PROCESSING

• US 20150309641A1
• Filed: 05/04/2015
• Published: 10/29/2015
• Est. Priority Date: 01/05/2007
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: HOTELLING, Steven P., HAMBLIN, Mark Arthur, LAND, Brian R.
• Granted Patent: US 10,613,665 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 2203/04101 2.5D-digitiser, i.e. digitiser detecting the X/Y position of the input means, finger or stylus, also when it does not touch, but is proximate to the digitiser's interaction surface and also measures the distance of the input means within a short range in the Z direction, possibly with a separate measurement setup
• CPC Class Codes: G06F 2203/04104 Multi-touch detection in digitiser, i.e. details about the simultaneous detection of a plurality of touching locations, e.g. multiple fingers or pen and finger
• CPC Class Codes: G06F 2203/04105 Pressure sensors for measuring the pressure or force exerted on the touch surface without providing the touch position
• CPC Class Codes: G06F 2203/04111 Cross over in capacitive digitiser, i.e. details of structures for connecting electrodes of the sensing pattern where the connections cross each other, e.g. bridge structures comprising an insulating layer, or vias through substrate
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• 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 3/0445 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
• CPC Class Codes: G06F 3/0447 Position sensing using the local deformation of sensor cells
• CPC Class Codes: G06F 3/045 using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact
• CPC Class Codes: G09G 3/36 using liquid crystals

Abstract

A multi-touch sensor panel is disclosed that can be produced by forming a plurality of first traces of substantially transparent conductive material on a first substrate, forming a plurality of second traces of the substantially transparent material, and creating a fluid-tight gap between the plurality of first traces and the plurality of second traces. The fluid-tight gap can then be filled with a fluid having substantially no bubbles and an optical index similar to the optical index of the first and second traces to make the gap and the first and second traces substantially transparent. The second and first traces can be oriented to cross over each other at crossover locations separated by the fluid, the crossover locations forming mutual capacitance sensors for detecting touches.

Claims

1. A method for determining an amount of force being applied to a touch screen, comprising:

forming a plurality of first traces of substantially transparent conductive material on a first substrate;

forming a plurality of second traces of the substantially transparent conductive material;

creating a fluid-tight gap between the plurality of first traces and the plurality of second traces;

filling the fluid-tight gap with a dielectric fluid having an optical index that substantially matches the optical index of the first and second traces to make the gap and the first and second traces substantially transparent; and

determining the amount of the applied force based on a change in the fluid-tight gap and a separation of the plurality of first and second traces due to the applied force.

2. The method of claim 1, wherein the first substrate is a cover glass having a first side capable of being touched, and a second side opposite the first side on which the plurality of first traces are formed.

3. The method of claim 2, further comprising forming the plurality of second traces on a second substrate.

4. The method of claim 1, further comprising maintaining the fluid-tight gap by forming compressible spacers in the fluid-tight gap, the compressible spacers capable of being compressed during the application of the force.

5. A method for determining an amount of force being applied to a touch screen, comprising:

forming a plurality of first traces and a plurality of second traces of substantially transparent conductive material;

separating the plurality of first traces and the plurality of second traces with a fluid having an optical index that substantially matches the optical index of the plurality of first traces and the plurality of second traces to make the plurality of first traces and the plurality of second traces substantially transparent, the fluid selected to have dielectric properties to enable a capacitance to be generated at the plurality of first traces and the plurality of second traces; and

determining the amount of the applied force based on a change in the capacitance at the plurality of first traces and the plurality of second traces.

6. The method of claim 5, further comprising forming the plurality of first traces on a second side of a first substrate having a first side capable of being touched, the second side opposite the first side.

7. The method of claim 6, further comprising forming the plurality of second traces on a second substrate.

8. The method of claim 5, further comprising separating the plurality of first traces and the plurality of second traces using compressible spacers, the compressible spacers capable of being compressed during the application of the force and changing the capacitance at the plurality of first traces and the plurality of second traces.

9. A force-sensitive touch screen, comprising:

a first substrate having a plurality of first traces of substantially transparent conductive material formed thereon;

a plurality of second traces of the substantially transparent material;

a fluid-tight gap formed between the plurality of first traces and the plurality of second traces; and

a dielectric fluid in the fluid-tight gap, the dielectric fluid having an optical index that substantially matches the optical index of the plurality of first traces and the plurality of second traces, the fluid for making the gap and the plurality of first traces and the plurality of second traces substantially transparent;

wherein the fluid-tight gap is configured to enable a change in separation of the plurality of first traces and the plurality of second traces upon an application of force to the touch screen.

10. The force-sensitive touch screen of claim 9, wherein the first substrate is a cover glass having a first side capable of being touched, and a second side opposite the first side on which the plurality of first traces are formed.

11. The force-sensitive touch screen of claim 10, further comprising a second substrate having the plurality of second traces formed thereon.

12. The force-sensitive touch screen of claim 9, further comprising compressible spacers coupled between the plurality of first and second traces, the compressible spacers capable of being compressed during the application of force.

13. The force-sensitive touch screen of claim 9, the force-sensitive touch screen incorporated into a computing system.

14. The force-sensitive touch screen of claim 13, the computing system incorporated into a mobile telephone.

15. The force-sensitive touch screen of claim 13, the computing system incorporated into a portable computing device.

16. A force-sensitive touch screen, comprising:

first and second means for capacitive sensing separated by a fluid-tight gap;

means for filling the fluid-type gap having dielectric properties and an optical index that substantially matches an optical index of the first and second means; and

means for changing the separation of the first and second means upon an application of force to the touch screen.

17. The force-sensitive touch screen of claim 16, further comprising a cover glass having a first side capable of being touched, and a second side opposite the first side on which the first means are formed.

18. The force-sensitive touch screen of claim 17, further comprising a second substrate having the second means formed thereon.

19. The force-sensitive touch screen of claim 16, further comprising third means coupled between the first and second means, the third means capable of being compressed during an application of force to the force-sensitive touch screen.

20. The force-sensitive touch screen of claim 16, the force-sensitive touch screen incorporated into a portable computing device.