Mitigating noise in capacitive sensor

Patent metadata

Field	Value
Publication number	US-10198123-B2
Application number	US-201415306054-A
Country	US
Kind code	B2
Filing date	Apr 21, 2014
Priority date	Apr 21, 2014
Publication date	Feb 5, 2019
Grant date	Feb 5, 2019

Abstract

The disclosed embodiments relate to forming an area on a touchscreen which electrically isolates a portion of the viewable area of the touchscreen from a capacitive sensor associated with the touchscreen.

First claim

What is claimed is:

1. A touchscreen comprising:
a liquid crystal display having an upper surface area and a lower surface area;
a capacitive array adjacent said lower surface area;
an optically transparent electrically conductive layer deposited between said lower surface area and said capacitive array, said layer including:
a first area electrically isolating said liquid crystal display and said capacitive array, said first area including less than said upper surface area, and a second area permitting electrical transmission between said upper surface area and said capacitive array.

2. The touchscreen of claim 1 wherein said optically transparent electrically conductive layer includes indium tin oxide.

3. The touchscreen of claim 1 wherein said optically transparent electrically conductive layer includes silver nanowire matrix.

4. The touchscreen of claim 1 wherein said optically transparent electrically conductive layer is deposited on a thin film transistor layer in said liquid crystal display.

5. The touchscreen of claim 1 wherein said optically transparent electrically conductive layer is deposited on a transparent substrate between said liquid crystal display and said capacitive array.

6. The touchscreen of claim 1 wherein said first area and said second area are separated by an interface area formed on said optically transparent electrically conductive layer.

7. The touchscreen of claim 1 wherein said second area is electromagnetically connected to a processor, thereby facilitating detection of an object adjacent the liquid crystal display and above the second area.

8. An electronic device comprising:
a housing;
a touchscreen in said housing, said touchscreen including: a liquid crystal display having an upper surface area and a lower surface area;
a capacitive array beneath said lower surface area;
an optically transparent electrically conductive layer deposited between said lower surface area and said capacitive array, said layer including: a first area less in size than said upper surface area, and a second area electrically isolated from the first area, the second area operative to capacitively sense an object adjacent the touchscreen.

9. The electronic device of claim 8 wherein said optically transparent electrically conductive layer includes one of indium tin oxide and silver nanowire.

10. The electronic device of claim 8 wherein said optically transparent electrically conductive layer is deposited on a thin film transistor layer in said liquid crystal display.

11. The electronic device of claim 8 wherein said optically transparent electrically conductive layer is deposited on a transparent substrate between said liquid crystal display and said capacitive array.

12. The electronic device of claim 8 wherein said first area is approximately centered within said second area.

13. The electronic device of claim 8 wherein said first area is offset within said second area.

14. The electronic device of claim 8 wherein said first area and said second area are separated by an interface area formed on said optically transparent electrically conductive layer.

Assignees

• Apple Inc

Inventors

• Chen Cheng
• Uttermann Erik A
• Gibbs Kevin D
• Agarwal Manu
• Grunthaner Martin P

Classifications

• G06F3/0418 Primary

  for error correction or compensation, e.g. based on parallax, calibration or alignment · CPC title

• G02F2001/133302

  Physics · mapped topic

• G06F2203/04106

  Multi-sensing digitiser, i.e. digitiser using at least two different sensing technologies simultaneously or alternatively, e.g. for detecting pen and finger, for saving power or for improving position detection · CPC title

• G06F2203/04107

  Shielding in digitiser, i.e. guard or shielding arrangements, mostly for capacitive touchscreens, e.g. driven shields, driven grounds · CPC title

• G02F1/13338

  Input devices, e.g. touch panels · CPC title