BACK OF COVER TOUCH SENSORS

• US 20180067584A1
• Filed: 08/30/2017
• Published: 03/08/2018
• Est. Priority Date: 09/06/2016
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: ZHU, Wencong, LIN, Albert, PENN, Alexander A., GOGTE, Ashray Vinayak, TUNG, Chun-Hao, ZHANG, Hao, ZHOU, Hui, ZHONG, John Z., HOTELLING, Steven P., MONDAL, Sudip, RANGANATHAN, Sumant, KANG, Sunggu
• Granted Patent: US 10,444,918 B2
• Time in Patent Office: Days
• CPC Class Codes: G06F 2203/04103 Manufacturing, i.e. details related to manufacturing processes specially suited for touch sensitive devices
• CPC Class Codes: G06F 2203/04107 Shielding in digitiser, i.e. guard or shielding arrangements, mostly for capacitive touchscreens, e.g. driven shields, driven grounds
• CPC Class Codes: G06F 3/04164 Connections between sensors and controllers, e.g. routing lines between electrodes and connection pads
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes

Abstract

Touch sensor configurations for reducing electrostatic discharge events in the border area of a touch sensor panel is disclosed. Touch sensors (e.g., electrodes formed on the cover material and/or the opaque mask) can be susceptible to certain events such as arcing and discharge/joule heating, which may negatively affect touch sensor performance. Examples of the disclosure can include increasing the trace width, spacing, and/or thickness in the border area relative to the trace width, spacing, and/or thickness in the visible/active area along one or more sides of the touch sensor panel. In some examples, touch electrodes can be located exclusively in the visible/active areas along one or more sides of the touch sensor panel, while dummy sections can be included in both the border and visible/active areas. Additionally or alternatively, one or more gaps between adjacent touch electrodes in the border area or serpentine routing can be included.

Claims

1. A touch sensor panel comprising:

an opaque mask located in a border area and contacting at least a portion of a conductive material;

a plurality of touch electrodes configured to detect a touch, at least a portion of the plurality of touch electrodes located in a visible area of the touch sensor panel;

a plurality of electrode channels defined by the plurality of touch electrodes, wherein each of the plurality of electrode channels includes a space between adjacent touch electrodes;

a plurality of bond pads located in a border area of the touch sensor panel;

a border channel located between at least one of the plurality of touch electrodes and at least one of the plurality of bond pads; and

a plurality of routing traces, each routing trace configured to route one of the plurality of touch electrodes to one of the plurality of bond pads,

a first portion of the routing trace is located in one of the plurality of electrode channels, a second portion of the routing trace is located in the border channel in the visible area, and a third portion of the routing trace is located in the border channel in the border area,

wherein one or more of the width, thickness, and spacing to an adjacent routing trace of the first portion is less than the second portion, and

one or more of the width, thickness, and spacing to the adjacent routing trace of the second portion is less than the third portion.

2. The touch sensor panel of claim 1, wherein at least a portion of the plurality of routing traces located in the border area is formed of the conductive material.

3. The touch sensor panel of claim 1, further comprising:

a plurality of conductive sections located exclusively in the border area of one or more sides of the touch sensor panel, each conductive section electrically coupled to one of the routing traces,

wherein the routing trace is disposed only on a portion of the conductive section.

4. The touch sensor panel of claim 3, wherein the plurality of conductive sections is located exclusively in the border area of all sides of the touch sensor panel.

5. A touch sensor panel comprising:

an opaque mask located in a border area and contacting at a least a portion of a conductive material;

a plurality of touch electrodes configured to detect a touch, the plurality of touch electrodes located in a visible area of the touch sensor panel; and

one or more dummy sections formed from the conductive material, each dummy section having a first portion located in the visible area and a second portion located in the border area.

6. The touch sensor panel of claim 5, wherein the plurality of touch electrodes is located exclusively in the visible area along one or more sides of the touch sensor panel.

7. The touch sensor panel of claim 6, wherein the plurality of touch electrodes is located exclusively in the visible area along all sides of the touch sensor panel.

8. The touch sensor panel of claim 5, wherein the plurality of touch electrodes are formed from the conductive material.

9. The touch sensor panel of claim 5, further comprising:

an overlap between an inner edge of the opaque mask and an outer edge of each of the plurality of dummy sections,

wherein the overlap is greater than or equal to 1 microns.

10. The touch sensor panel of claim 5, wherein some of the plurality of touch electrodes include a first portion located in the border area and a second portion located in the visible area, the touch sensor panel further comprising:

a gap located between adjacent first portions,

wherein one or more first dummy sections are included in the plurality of dummy sections, the one or more first dummy sections including a plurality of spatially separated sections of the conductive material located in the border area.

11. The touch sensor panel of claim 10, further comprising:

a first overlap between an inner edge of the opaque mask and an outer edge of each of the plurality of dummy sections; and

a second overlap between the inner edge of the opaque mask and an outer edge of each of the plurality of touch electrodes,

wherein the second overlap can be greater than or equal to the first overlap.

12. A touch sensor panel comprising:

an opaque mask located in a border area and contacting at a least a portion of a conductive material;

a plurality of bond pads located in a border area of the touch sensor panel;

a plurality of touch electrodes configured to detect a touch, the plurality of touch electrodes located in a visible area of the touch sensor panel, the plurality of touch electrodes comprising;

a plurality of first touch electrodes, and

a plurality of second touch electrodes, the plurality of second touch electrodes located further from the plurality of bond pads than the plurality of first touch electrodes;

a plurality of electrode channels defined by the plurality of touch electrodes, wherein each of the plurality of electrode channels includes a space between adjacent touch electrodes; and

a plurality of routing traces, the plurality of routing traces comprising;

a plurality of first routing traces, each first routing trace configured to electrically couple one of the plurality of first touch electrodes to one of the plurality of bond pads, and

a plurality of second routing traces, each second routing trace configured to electrically couple one of the plurality of second touch electrodes to one of the plurality of bond pads,

wherein for each first routing trace has the same resistance as each adjacent second routing trace.

13. The touch sensor panel of claim 12, wherein each first touch electrode is smaller than each second touch electrode.

14. The touch sensor panel of claim 12, wherein the plurality of second routing traces is routed inside at least one of the plurality of electrode channels, and

each of the plurality of first routing traces is routed along at least two edges an electrically coupled first touch electrode and at least partially routed outside of the plurality of electrode channels.

15. The touch sensor panel of claim 12, further comprising:

one or more dummy sections located between at least one first touch electrode and at least one electrically coupled first routing trace.

16. The touch sensor panel of claim 12, wherein each first touch electrode is electrically coupled to two first routing traces, wherein the two first routing traces are routed along three edges of the first touch electrode.

17. The touch sensor panel of claim 12, wherein a length of each first routing trace is equal to a length of an adjacent second routing trace.

18. A method for forming a touch sensor panel, the method comprising:

providing a cover material;

depositing an opaque mask on the cover material;

depositing a conductive material on the cover material and the opaque mask;

patterning the conductive material in a border area of the touch sensor panel to form a plurality of bond pads, a first portion of a plurality of routing traces, and a first portion of one or more dummy sections; and

patterning the conductive material in a visible area of the touch sensor panel to form a plurality of touch electrodes, a second portion of the plurality of routing traces, and a second portion of the plurality of dummy sections.

19. The method of claim 18, wherein patterning the conductive material in the visible area of the touch sensor panel includes forming a first portion of the touch electrodes, the method further comprising:

patterning the conductive material in the border area of the touch sensor panel to form a second portion of the touch electrodes; and

locating the first and second portions of the plurality of dummy sections between adjacent touch electrodes.

20. The method of claim 19, further comprising:

locating at least two of the plurality of dummy sections between the adjacent touch electrodes.