Noise-cancelled capacitive touch display apparatus

• US 10,216,327 B2
• Filed: 02/27/2015
• Issued: 02/26/2019
• Est. Priority Date: 03/20/2014
• Status: Active Grant

• Current Assignee: PixArt Imaging Incorporated
• Original Assignee: PixArt Imaging Incorporated
• Inventors: Yang, Kuan-Yi
• Primary Examiner(s): Azari, Sepehr
• Application Number:
  US14/633,456
• Publication Number:
  US 20150268794A1
• Time in Patent Office: 1,460 Days
• CPC Class Codes: G06F 3/04184 Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally
• 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

Abstract

A noise-cancelled capacitive touch display apparatus includes a display panel and a capacitive touch sensor on or above the display panel. The capacitive touch sensor includes plural sensing lines, plural driving lines, plural first signal lines, plural second signal lines and a noise cancellation line. The sensing lines are parallel with each other and extend along a first direction. The driving lines are parallel with each other and extend along a second direction, wherein the second direction intersects the first direction. Each first signal line is located outside of an outermost driving line. Each second signal line is located outside of an outermost sensing line. The noise cancellation line is a cut-off part of a corresponding first signal line or a corresponding second signal line. The noise cancellation line receives the noise generated from the display panel.

Claims

1. A noise-cancelled capacitive touch display apparatus, comprising:

a display panel; and

a capacitive touch sensor on or above the display panel, wherein the capacitive touch sensor includes;

a first electrode and a second electrode which form a mutual capacitance in between, for sensing a signal;

a signal line, which is located outside of the first electrode or the second electrode, wherein when the signal line is located outside of the first electrode, from a top view in a direction perpendicular to the display panel, the signal line overlaps or does not overlap with the second electrode, and when the signal line is located outside of the second electrode, from the top view, the signal line overlaps or does not overlap with the first electrode; and

a noise cancellation line for receiving a noise generated from the display panel, wherein the signal line includes a thicker portion and a thinner portion such that the thinner portion forms an inward recess to accommodate the noise cancellation line, whereby the signal line, the noise cancellation line and a gap formed between the signal line and the noise cancellation line, form a rectangle shape, and wherein the signal line and the noise cancellation line are at different voltage levels, and wherein the signal line and the noise cancellation line are located at a same elevation level from a cross sectional view in a direction parallel to the display panel;

wherein the signal line and the second electrode are at different voltage levels such that the signal line and a part of the second electrode form an electric field wall.

2. The noise-cancelled capacitive touch display apparatus of claim 1, wherein:

the first electrode includes a plurality of sensing lines, which are parallel with each other and extend along a first direction; and

the second electrode includes a plurality of driving lines, which are parallel with each other and extend along a second direction, wherein the sensing lines and the driving lines intersect with each other from the top view to form a capacitive electric field, and are located at different elevation levels from a cross sectional view, and wherein the second direction is orthogonal to the first direction;

wherein;

when the signal line is located outside of an outermost driving line in the first direction and parallel to the second direction, a longer side of the rectangle shape is at least as long as the driving line; and

when the signal line is located outside of an outermost sensing line in the second direction and parallel to the first direction, a longer side of the rectangle shape is at least as long as the sensing line.

3. The noise-cancelled capacitive touch display apparatus of claim 2, wherein the signal line, the noise cancellation line and the driving lines are located at the same elevation level from the cross sectional view.

4. The noise-cancelled capacitive touch display apparatus of claim 2, wherein the driving lines are above the signal line and the noise cancellation line from the cross sectional view.

5. The noise-cancelled capacitive touch display apparatus of claim 1, wherein a thickness of the noise cancellation line is smaller than a thickness of each driving line.

6. The noise-cancelled capacitive touch display apparatus of claim 1, wherein a width of the noise cancellation line is smaller than or equal to a width of the signal line.

7. The noise-cancelled capacitive touch display apparatus of claim 2, wherein the capacitive touch sensor further includes a substrate, and wherein the sensing lines are at a first side of the substrate and the driving lines and the noise cancellation line are at a second side of the substrate opposite to the first side.

8. The noise-cancelled capacitive touch display apparatus of claim 2, wherein a voltage level of the signal line is higher than or lower than a voltage level of each driving line.