Seamless capacitive touch panel

• US 9,170,695 B2
• Filed: 01/20/2014
• Issued: 10/27/2015
• Est. Priority Date: 09/01/2011
• Status: Active Grant

• Current Assignee: Wistron Corporation
• Original Assignee: Wistron Corporation
• Inventors: Wang, Kuei-Ching, Lin, Hsing-Chiao
• Primary Examiner(s): GIRARDI, VANESSA MARY
• Application Number:
  US14/159,373
• Publication Number:
  US 20140125630A1
• Time in Patent Office: 645 Days
• Field of Search: 200/600, 345/173
• US Class Current: 1/1
• CPC Class Codes: G06F 2203/04111 Cross over in capacitive digitiser, i.e. details of structures for connecting electrodes of the sensing pattern where the connections cross each other, e.g. bridge structures comprising an insulating layer, or vias through substrate
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• 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 seamless capacitive touch panel includes a substrate, a pattern layer, a first electrode, and a second electrode. The pattern layer is formed on the substrate. The first electrode is formed on the pattern layer. The second electrode is formed on the substrate. The first electrode and the second electrode are separated by the pattern layer for preventing conduction between the first and second electrodes.

Claims

1. A capacitive touch panel, comprising:

a substrate, having a surface;

a raised pattern layer formed directly on a first portion of the surface of the substrate, the raised pattern layer having a bottom surface, a top surface opposite to the bottom surface, and a surrounding edge connected between the top surface and the bottom surface;

a first electrode formed directly on the top surface of the pattern layer; and

a second electrode formed directly on a second portion of the surface of the substrate adjacent to the raised pattern layer so that a capacitance is formed between the first electrode and the second electrode;

wherein the second electrode and the first electrode are disposed at different heights on the substrate and separated by the raised pattern layer for preventing conduction between the first and second electrodes and reducing of a seam between the first and second electrodes when viewing from a top.

2. The capacitive touch panel of claim 1, wherein an orthogonal projection of the first electrode is adjacent to an orthogonal projection of the second electrode.

3. The capacitive touch panel of claim 1, wherein an orthogonal projection of the first electrode adjoins an orthogonal projection of the second electrode.

4. The capacitive touch panel of claim 1, wherein the pattern layer is made of photoresist.

5. The capacitive touch panel of claim 1, wherein the first and second electrodes are made of transparent conductive material consisting of indium tin oxide (ITO), antimony tin oxide (ATO), indium zinc oxide (IZO), aluminum zinc oxide (AZO), gallium zinc oxide (GZO), micaceous iron oxide (MIO), or metal oxide selected from titanium oxide, zinc oxide, zirconium oxide, antimony oxide, indium oxide, tin oxide, aluminum oxide, or silicon oxide.

6. The capacitive touch panel of claim 1, further comprising:

an isolating layer formed on the first electrode and the second electrode; and

a conductive layer formed on the isolating layer for electrically connecting a section of the second electrode to another section of the second electrode separated by the pattern layer via through holes formed on the isolating layer.

7. The capacitive touch panel of claim 1, further comprising:

a conductive layer formed beneath the pattern layer for electrically connecting a section of the second electrode to another section of the second electrode separated by the pattern layer.

8. The capacitive touch panel of claim 1, wherein the first electrode and the second electrode are orthogonal to each other.

9. The capacitive touch panel of claim 1, wherein an undercut is formed at the surrounding edge of the raised pattern layer.

10. The capacitive touch panel of claim 9, wherein an area of the top surface is greater than an area of the bottom surface to form the undercut.

11. The capacitive touch panel of claim 1, wherein the substrate is a substrate of a display panel integrated with the capacitive touch panel.

12. The capacitive touch panel of claim 11, wherein the substrate is a color filter glass substrate of the display panel.

13. A method of fabricating a capacitive touch panel, comprising the steps of:

forming a raised pattern layer directly on a first portion of a surface of a substrate, the raised pattern layer having a bottom surface, a top surface opposite to the bottom surface, and a surrounding edge connected between the top surface and the bottom surface;

forming a first electrode directly on the top surface of the pattern layer; and

forming a second electrode directly on a second portion of the surface of the substrate;

wherein the second electrode and the first electrode are disposed at different heights on the substrate and separated by the raised pattern layer for preventing conduction between the first and second electrodes and reducing of a seam between the first and second electrodes when viewing from a top.

14. The method of claim 13, further comprising:

forming an isolating layer on the first electrode and the second electrode; and

forming a conductive layer on the isolating layer for electrically connecting a section of the second electrode to another section of the second electrode separated by the pattern layer via through holes formed on the isolating layer.

15. The method of claim 13, further comprising:

forming a conductive layer beneath the pattern layer for electrically connecting a section of the second electrode to another section of the second electrode separated by the pattern layer.

16. The method of claim 13, wherein the substrate is a substrate of a display panel integrated with the capacitive touch panel.

17. The method of claim 16, wherein the substrate is a color filter glass substrate of the display panel.