Periphery Conductive Element for Touch Screen

• US 20110285661A1
• Filed: 08/05/2010
• Published: 11/24/2011
• Est. Priority Date: 05/18/2010
• Status: Abandoned Application

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: HOTELLING, Steven Porter
• Application Number:
  US12/851,401
• Publication Number:
  US 20110285661A1
• Time in Patent Office: Days
• US Class Current: 345/174
• CPC Class Codes: G06F 2203/04113 Peripheral electrode pattern in resistive digitisers, i.e. electrodes at the periphery of the resistive sheet are shaped in patterns enhancing linearity of induced field
• CPC Class Codes: G06F 3/0418 for error correction or compensation, e.g. based on parallax, calibration or alignment
• 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: H03K 17/9622 using a plurality of detectors, e.g. keyboard
• CPC Class Codes: H03K 2217/96077 comprising an electrode which is floating
• CPC Class Codes: H03K 2217/960785 with illumination

Abstract

A touch screen is disclosed. The touch screen can include a touch panel and a display, where the display can have a conductive element coupled to or disposed along at least one side at a periphery of a conductive layer of the display. The conductive element can drive the conductive layer from multiple positions along the element to provide a grounding shield for the touch screen. The grounding shield can shunt display interference to ground rather than into the touch panel. The conductive element can also drive the conductive layer from multiple positions along the element, thereby providing an increased bandwidth, to quickly reach an appropriate voltage in association with the touch panel, consequently improving the touch sensitivity of the panel. The conductive element can include multiple configurations, e.g., a ring around a perimeter of the conductive layer, a partial ring around three sides of the periphery of the conductive layer, two elements on opposite sides at the periphery, and one element along one side at the periphery. The conductive element can be continuous or segmented.

Claims

1. A device comprising:

a conductive layer configured to form a shield; and

a conductive element disposed along at least one side at a periphery of the conductive layer to electrically contact the conductive layer at multiple positions at the periphery and configured to drive the formation of the shield from the multiple positions.

2. The device of claim 1, wherein the conductive element is disposed in a ring around the perimeter of the conductive layer.

3. The device of claim 1, wherein the conductive element is disposed along three sides of the conductive layer.

4. The device of claim 1, wherein the conductive element is disposed along opposite sides of the conductive layer.

5. The device of claim 1, wherein the conductive element is disposed along one side of the conductive layer.

6. The device of claim 1, wherein the conductive element is configured to drive a voltage into the conductive layer to form the shield.

7. The device of claim 1, wherein the conductive layer comprises a transparent conductor.

8. The device of claim 1, wherein the conductive element comprises a non-transparent conductor.

9. A touch screen comprising:

a touch panel configured to detect a touch proximate thereto; and

a display adjacent to the touch panel, the display including a conductive layer and a conductive element disposed along at least one side at the periphery of the conductive layer to electrically contact the conductive layer at multiple positions at the periphery, the conductive element driving the conductive layer to limit display noise interfering with the touch panel detecting the touch.

10. The touch screen of claim 9, wherein the display includes a first polarizer adjacent to the touch panel, the conductive layer having the conductive element disposed thereon adjacent to the first polarizer, a color filter adjacent to the conductive layer, a liquid crystal layer adjacent to the color filter, a thin film transistor layer adjacent to the liquid crystal layer, and a second polarizer adjacent to the thin film transistor layer.

11. The touch screen of claim 10, wherein the conductive layer shields the touch panel from noise of at least the thin film transistor layer.

12. The touch screen of claim 9, wherein the display includes the conductive layer having the conductive element disposed thereon adjacent to the touch panel, a first polarizer adjacent to the conductive layer, a color filter adjacent to the first polarizer, a liquid crystal layer adjacent to the color filter, a thin film transistor layer adjacent to the liquid crystal layer, and a second polarizer adjacent to the thin film transistor layer.

13. A method comprising:

driving a voltage through a conductive element disposed along a periphery of a conductive layer;

transmitting the voltage through the conductive layer from multiple positions along the conductive element; and

forming the conductive layer into a grounding shield via the transmitted voltage.

14. The method of claim 13, wherein driving a voltage comprises driving a voltage around a perimeter of the conductive layer.

15. The method of claim 13, wherein driving a voltage comprises driving the voltage along at least one side of the conductive layer.

16. The method of claim 13, wherein forming the conductive layer comprises forming the conductive layer to shunt noise to ground.

17. A method comprising:

driving a voltage through a conductive element disposed along at least one side at a periphery of a conductive layer to electrically contact the conductive layer at multiple positions at the periphery;

transmitting the voltage through the conductive layer; and

modulating the voltage in the conductive layer substantially as another voltage in an adjacent touch sensing device.

18. The method of claim 17, wherein transmitting the voltage comprises transmitting the voltage toward a center of the conductive layer from a ring around the perimeter of the conductive layer.

19. The method of claim 17, wherein transmitting the voltage comprises transmitting the voltage toward a center of the conductive layer from at least two sides of the conductive layer.

20. The method of claim 17, wherein transmitting the voltage comprises transmitting the voltage from one side of the conductive layer to an opposite side.

21. The method of claim 17, wherein modulating the voltage comprises substantially matching voltage waveforms between the conductive layer and the touch sensing device to adjust sensitivity of the touch sensing device.

22. A touch screen comprising:

a touch panel including electrodes configured to modulate a first voltage waveform; and

a display including a conductive layer configured to modulate a second voltage waveform and a conductive element disposed along a periphery of the conductive layer to drive the conductive layer from multiple positions along the conductive element,

wherein the first and second voltage waveforms are substantially the same.

23. The touch screen of claim 22, wherein the electrodes are self capacitive.

24. The touch screen of claim 22, wherein the conductive element comprises multiple segments configured to drive the conductive layer together or in sequence.

25. The touch screen of claim 22 incorporated into at least one of a mobile telephone, a personal computer, or a digital media player.