Touchscreen electrode configuration

• US 8,599,150 B2
• Filed: 10/29/2009
• Issued: 12/03/2013
• Est. Priority Date: 10/29/2009
• Status: Active Grant

• Current Assignee: BOE Technology Group Co., Ltd.
• Original Assignee: Atmel Corporation (Microchip Technology Incorporated)
• Inventors: Philipp, Harald
• Primary Examiner(s): Beck, Alexander S
• Assistant Examiner(s): Truong, Nguyen H
• Application Number:
  US12/608,779
• Publication Number:
  US 20110102361A1
• Time in Patent Office: 1,496 Days
• Field of Search: 345173-178, 178 1801- 1803, 178/18.05, 178/18.06, 178/19.03
• US Class Current: 345/173
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G02F 1/134309 characterised by their geometrical arrangement
• CPC Class Codes: G02F 1/13439 characterised by their electrical, optical, physical properties; materials therefor; method of making
• CPC Class Codes: G06F 1/169 the I/O peripheral being an integrated pointing device, e.g. trackball in the palm rest area, mini-joystick integrated between keyboard keys, touch pads or touch stripes G06F1/1643 takes precedence; constructional details of pointing devices G06F3/033
• 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 3/041 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
• 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

Abstract

A touchscreen includes touchscreen electrode elements distributed across an active area of a substrate, and the touchscreen overlays a display. The touchscreen electrode elements are configured to avoid creating moiré patterns between the display and the touchscreen, such as angled, wavy, zig-zag, or randomized lines. In a further example, the electrodes form a mesh pattern configured to avoid moiré patterns.

Claims

1. An assembly, comprising:

a first mesh of touchscreen electrode elements distributed across at least an active area of a substrate, the first mesh configured to avoid visible moire patterns when overlaying a display having a regular repeating pattern of pixels, wherein the first mesh of touchscreen electrode elements has a first pattern; and

a second mesh of touchscreen electrode elements distributed across at least an active area of a substrate and overlapping the first mesh, the second mesh configured to avoid visible moiré

patterns when overlaying a display having a regular repeating pattern of pixels, wherein the second mesh of touchscreen electrode elements has a second pattern, the second pattern being different than the first pattern;

wherein at least one of the first and second patterns comprises a series of wavy lines and the other of the first and second patterns comprises a plurality of substantially straight line segments so as to form a diamond-shaped pattern; and

wherein the first and second meshes are further configured to have the same pitch, such that mesh intersections in the first mesh occur in open spaces in the second mesh, and mesh intersections in the second mesh occur in open spaces in the first mesh.

2. The assembly of claim 1, further comprising multiple electrode connections coupled to each mesh, and a plurality of breaks in the mesh separating adjacent electrodes from one another.

3. The assembly of claim 2, wherein the multiple electrode connections are formed with the same pitch as the coupled mesh, such that a configuration of the connection between the electrode connections and the mesh remain consistent across the mesh.

4. The assembly of claim 1, wherein:

the at least one of the first and second patterns that comprises a series of wavy lines comprises a mesh of wavy lines; and

the other of the first and second patterns that comprises a plurality of substantially straight line segments comprises a mesh of diamonds.

5. The assembly of claim 4, wherein the mesh of diamonds comprises oblique diamonds.

6. The assembly of claim 1, wherein at least one of the first and second meshes is broken along one or more zone edges to create multiple electrically separate zones within the mesh.

7. The assembly of claim 1, wherein the touchscreen electrode elements of at least one of the first and second meshes comprise fine line metal elements of 10 or less micrometers in width.

8. The assembly of claim 1, wherein the touchscreen electrode elements of at least one of the first and second meshes comprise at least one of angled, wavy, zig-zag, or randomized lines.

9. The assembly of claim 1, wherein the touchscreen electrode elements of at least one of the first and second meshes have a line width 1/10 or less a sub-pixel size of the display.

10. The assembly of claim 1, wherein a spacing between touchscreen line elements of at least one of the first and second meshes is randomized.

11. The assembly of claim 1, wherein a distance between touchscreen line elements of at least one of the first and second meshes is at least 50 times the width of the lines.