Reduction of touch sensor pattern visibility using beamsplitters

• US 10,338,748 B1
• Filed: 02/22/2019
• Issued: 07/02/2019
• Est. Priority Date: 03/14/2013
• Status: Expired due to Fees

• Current Assignee: Neodrón Limited (Atlantic IP Services Limited)
• Original Assignee: Neodrón Limited (Atlantic IP Services Limited)
• Inventors: Yilmaz, Esat, Saran, Neerja
• Primary Examiner(s): Shankar, Vijay
• Assistant Examiner(s): Almeida, Cory A
• Application Number:
  US16/282,531
• Publication Number:
  US 20190187827A1
• Time in Patent Office: 130 Days
• Field of Search: 345173-179
• CPC Class Codes: G06F 3/042 by opto-electronic means
• CPC Class Codes: G06F 3/0421 by interrupting or reflecting a light beam, e.g. optical touch-screen
• 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: Y10S 977/742 Carbon nanotubes, CNTs

Abstract

In one embodiment, a touch sensor comprises a beamsplitter operable to reflect a first portion of light incident on the beamsplitter and transmit a second portion of light incident on the beamsplitter, a substrate, and one or more lines of conductive material disposed on the substrate, the lines of conductive material disposed between the first substrate and the beamsplitter.

Claims

1. An apparatus, comprising:

a display;

a first touch-sensor layer comprising a first plurality of conductive electrodes, wherein the first plurality of conductive electrodes comprises a metal mesh and is disposed on a first substrate;

a second touch-sensor layer comprising a second plurality of conductive electrodes, wherein the first plurality of conductive electrodes and the second plurality of conductive electrodes are electrically connected to one or more tracks of conductive material;

a beamsplitter operable to reflect a first portion of light incident on the coating and transmit a second portion of light incident on the coating, wherein the first portion of light is in the range of 30% to 95%, and the second portion of light is in the range of 5% to 70%;

wherein the beamsplitter is disposed above the first touch sensor layer;

wherein the beamsplitter is on a side of the first touch sensor layer opposite the display;

a touch-sensor controller configured to detect and process the change in capacitance at one or more touch-sensor nodes to determine the presence and location of a touch-sensor input, and further configured to communicate information about the touch-sensor input to one or more components of the apparatus; and

a flexible printed circuit electrically connected to the touch-sensor controller, wherein the one or more tracks of conductive material on the substrate is electrically connected to the flexible printed circuit.

2. The apparatus of claim 1, wherein the first plurality of conductive electrodes and the second plurality of conductive electrodes are configured to capacitively couple across a dielectric material.

3. The apparatus of claim 2, wherein a layer of anti-reflective coating is disposed above the first touch-sensor layer.

4. The apparatus of claim 3, wherein refractive indices of the beamsplitter, the first substrate, and the anti-reflective coating are substantially similar to each other.

5. The apparatus of claim 2, wherein the second plurality of conductive electrodes is disposed on a second substrate.

6. The apparatus of claim 2, wherein the second plurality of conductive electrodes is disposed on the opposite side of the first substrate.

7. The apparatus of claim 2, wherein the display comprises a liquid crystal display.

8. The apparatus of claim 2, wherein the beamsplitter is adjacently disposed on the first touch sensor layer.

9. The apparatus of claim 2, wherein a third substrate is disposed between the beamsplitter and the first touch sensor layer.

10. The apparatus of claim 2, wherein refractive indices of the beamsplitter and the first substrate are substantially similar to each other.

11. The apparatus of claim 1, wherein the beamsplitter is operative to reduce display issues caused by light reflecting off the first plurality of conductive electrodes.

12. The apparatus of claim 1, wherein the beamsplitter comprises a half-mirror coating disposed above the first plurality of conductive electrodes to reduce display issues caused by light reflecting off the first plurality of conductive electrodes.

13. An apparatus, comprising:

a display;

a first touch-sensor layer comprising a first plurality of conductive electrodes, wherein the first plurality of conductive electrodes is disposed on a first substrate, the first plurality of conductive electrodes comprising sense electrodes;

a second touch-sensor layer comprising a second plurality of conductive electrodes, wherein the first plurality of conductive electrodes and the second plurality of conductive electrodes are electrically connected to one or more tracks of conductive material;

wherein the first plurality of conductive electrodes and the second plurality of conductive electrodes are configured to capacitively couple across a dielectric material;

a beamsplitter operable to divide a light beam into two or more separate light beams, wherein the beamsplitter is disposed above the first touch sensor layer on a side of the first touch sensor layer opposite the display, wherein the beamsplitter is operable to reflect a first portion of light incident on the beamsplitter and transmit a second portion of light incident on the beamsplitter, wherein the first portion of light is in the range of 30% to 95%, and the second portion of light is in the range of 5% to 70%;

a touch-sensor controller configured to detect and process the change in capacitance at one or more touch-sensor nodes to determine the presence and location of a touch-sensor input, and further configured to communicate information about the touch-sensor input to one or more components of the apparatus; and

a flexible printed circuit electrically connected to the touch-sensor controller, wherein the one or more tracks of conductive material on the substrate is electrically connected to the flexible printed circuit.

14. The apparatus of claim 13, wherein the first portion of light is in the range of 50% to 75%, and the second portion of light is in the range of 25% to 50%.

15. The apparatus of claim 13, wherein the beamsplitter comprises a half-mirror coating to reduce the display issues caused by light reflecting off the first plurality of conductive electrodes.

16. The apparatus of claim 13, wherein the first plurality of conductive electrodes comprises a metal mesh.

17. The apparatus of claim 13, wherein the first plurality of conductive electrodes comprises indium tin oxide.

18. The apparatus of claim 13, wherein the second plurality of conductive electrodes is disposed on a second substrate.

19. The apparatus of claim 13, wherein the second plurality of conductive electrodes is disposed on the opposite side of the first substrate.