Touch screen sensor with low visibility conductors

• US 8,508,680 B2
• Filed: 08/21/2012
• Issued: 08/13/2013
• Est. Priority Date: 02/28/2008
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Geaghan, Bernard O., Hagermoser, Edward S.
• Primary Examiner(s): DUDEK, JAMES A
• Application Number:
  US13/590,333
• Publication Number:
  US 20120313880A1
• Time in Patent Office: 357 Days
• Field of Search: 349/12
• US Class Current: 349/12
• CPC Class Codes: G06F 2203/04112 Electrode mesh in capacitive digitiser: electrode for touch sensing is formed of a mesh of very fine, normally metallic, interconnected lines that are almost invisible to see. This provides a quite large but transparent electrode surface, without need for ITO or similar transparent conductive material
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• 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 3/0448 Details of the electrode shape, e.g. for enhancing the detection of touches, for generating specific electric field shapes, for enhancing display quality
• CPC Class Codes: G06F 3/045 using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact

Abstract

A touch screen sensor with a conductive micropattern includes one or more features to obscure or reduce the visibility of the conductive micropattern.

Claims

1. A touch screen sensor having a touch-sensitive surface comprising:

within a touch sensing area, a electrically conductive micropattern disposed on or in a visible light transparent substrate, wherein the micropattern includes conductive traces with width between about 1 and 10 micrometers; and

one or more light scattering elements in an optically continuous layer of substantially uniform optical density disposed between the micropattern and the touch-sensitive surface, and wherein the light scattering elements comprise microscopic features having a size greater than the width of the conductive traces.

2. The touch screen sensor of claim 1, wherein the optically continuous layer is associated with a substrate other than the visible light transparent substrate.

3. The touch screen sensor of claim 1, wherein the optically continuous layer comprises a polarizer.

4. The touch screen sensor of claim 1, wherein the optically continuous layer comprises an anti-glare or matte finish.

5. The touch screen sensor of claim 1, wherein the micropattern comprises pseudo-random variations in the micropattern.

6. The touch screen sensor of claim 1, wherein the microscopic feature comprises an anti-glare surface.

7. The touch screen sensor of claim 1, wherein the microscopic feature comprises light-diffracting bumps.

8. The touch screen sensor of claim 1, wherein the microscopic feature comprises light-diffracting pseudo-random or random surface structures.

9. The touch screen sensor of claim 1, wherein the microscopic feature comprises light-diffracting facets.