Touch sensor with plastic cover lens

• US 9,298,222 B2
• Filed: 12/19/2013
• Issued: 03/29/2016
• Est. Priority Date: 03/15/2013
• Status: Active Grant

• Current Assignee: Neodrón Limited (Atlantic IP Services Limited)
• Original Assignee: Atmel Corporation (Microchip Technology Incorporated)
• Inventors: Blair, Thomas, Yilmaz, Esat, SHAIKH, Jalil, Saran, Neerja
• Primary Examiner(s): BALAOING, ARIEL A
• Application Number:
  US14/135,329
• Publication Number:
  US 20140267099A1
• Time in Patent Office: 831 Days
• Field of Search: 345/173, 349/12
• US Class Current: 1/1
• CPC Class Codes: G06F 1/1692 the I/O peripheral being a secondary touch screen used as control interface, e.g. virtual buttons or sliders
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer

Abstract

According to one embodiment, an apparatus comprises a substrate, a touch sensor, and a cover lens. The touch sensor is disposed on the substrate. A conductive mesh forms portions of the touch sensor, and the conductive mesh comprises fine lines of metal. The cover lens is coupled to the touch sensor and is at most 0.4 mm thick. The cover lens comprises plastic.

Claims

1. An apparatus comprising:

a substrate;

a touch sensor disposed on the substrate;

a conductive mesh forming portions of the touch sensor, the conductive mesh comprising fine lines of metal; and

a cover lens coupled to the touch sensor, wherein;

the cover lens is less than or equal to 0.4 mm thick;

the cover lens comprises plastic; and

a retransmission level of the touch sensor is less than 140, wherein the retransmission level comprises a ratio between;

a difference between a peak voltage of a signal response of the touch sensor when a detected touch is grounded and a minimum voltage of a signal response of the touch sensor when a detected touch is not grounded; and

the peak voltage.

2. The apparatus of claim 1, wherein the plastic is at least one of polyethylene terephthalate and polymethyl methacrylate.

3. The apparatus of claim 1, wherein the plastic is polycarbonate.

4. The apparatus of claim 1, wherein the cover lens is less than or equal to 0.3 mm thick.

5. The apparatus of claim 1, wherein the cover lens is less than or equal to 0.2 mm thick.

6. The apparatus of claim 1, wherein the touch sensor is operable to disregard, as a touch, an effect caused by a liquid in contact with the cover lens.

7. The apparatus of claim 6, wherein the touch sensor is operable, after the liquid is removed, to properly detect a touch on a portion of the cover lens with which the liquid was in contact.

8. The apparatus of claim 1, wherein the touch sensor is operable to properly detect at least two simultaneous touches on the cover lens.

24. The apparatus of claim 1, wherein the cover lens is not coupled to a coating that includes a hydrophobic material.

9. A system comprising:

a display element operable to present a visual display;

a sensor element coupled to the display element, the sensor element comprising a plurality of electrode elements formed from a conductive mesh, the sensor element operable to detect an object;

a lens element coupled to the sensor element, wherein;

the lens element is less than or equal to 0.4 mm thick;

the lens element comprises plastic; and

a retransmission level of the sensor element is less than 140, wherein the retransmission level comprises a ratio between;

a difference between a peak voltage of a signal response of the touch sensor when a detected touch is grounded and a minimum voltage of a signal response of the touch sensor when a detected touch is not grounded; and

the peak voltage.

10. The system of claim 9, wherein the plurality of electrode elements comprise a sense element and a drive element capacitively coupled to the sense element.

11. The system of claim 10, wherein the sense element is disposed on a first surface of a substrate and the drive electrode is disposed on a second surface of the substrate.

12. The system of claim 9, wherein the plastic is at least one of polyethylene terephthalate and polymethyl methacrylate.

13. The system of claim 9, wherein the plastic is polycarbonate.

15. The system of claim 9, wherein the lens element is less than or equal to 0.2 mm thick.

16. The system of claim 9, wherein the sensor element is operable to disregard, as a touch, an effect caused by a liquid in contact with the lens element.

17. The system of claim 16, wherein the sensor element is operable, after the liquid is removed, to properly detect a touch on a portion of the lens element with which the liquid was in contact.

18. The system of claim 9, wherein the sensor element is operable to properly detect at least two simultaneous touches on the lens element.

14. An apparatus comprising:

a touch sensor comprising a conductive mesh forming a plurality of electrodes, the plurality of electrodes comprising;

a drive electrode; and

a sense electrode capacitively coupled to the drive electrode; and

a cover lens coupled to the touch sensor, wherein;

the cover lens is less than or equal to 0.4 mm thick;

the cover lens comprises plastic; and

a retransmission level of the touch sensor is less than 140, wherein the retransmission level comprises a ratio between;

a difference between a peak voltage of a signal response of the touch sensor when a detected touch is grounded and a minimum voltage of a signal response of the touch sensor when a detected touch is not grounded; and

the peak voltage.

19. The system of claim 14, wherein the lens element is less than or equal to 0.3 mm thick.

20. The apparatus of claim 14, wherein the cover lens is less than or equal to 0.3 mm thick.

21. The apparatus of claim 14, wherein the cover lens is less than or equal to 0.2 mm thick.

22. The apparatus of claim 14, wherein the plastic is at least one of polyethylene terephthalate and polymethyl methacrylate.

23. The apparatus of claim 14 further comprising an anti-reflective coating disposed on the cover lens.