Capacitive Touch Panel with Low Impedance

• US 20090085891A1
• Filed: 09/29/2008
• Published: 04/02/2009
• Est. Priority Date: 09/29/2007
• Status: Active Grant

• Current Assignee: AU Optronics Corporation
• Original Assignee: AU Optronics Corporation
• Inventors: Hsieh, Yao-Jen, Yang, Tun-Chun, Hu, Chih-Jen, Lee, Seok-Lyul, Wu, Yuan-Chun, Lee, Hsin-Hung, Ma, Mei-Sheng, Li, Chun-Huai, Cheng, Kuo-Hsing
• Granted Patent: US 9,166,582 B2
• Time in Patent Office: Days
• US Class Current: 345/174
• CPC Class Codes: G01R 31/28 Testing of electronic circuits, e.g. by signal tracer EMC, EMP or similar testing of electronic circuits G01R31/002; testing for short-circuits, discontinuities, leakage or incorrect line connection G01R31/50; checking computers or computer components G06F11/00; checking static stores for correct operation G11C29/00 ; testing receivers or transmitters of transmission systems H04B17/00
• CPC Class Codes: G06F 2203/04103 Manufacturing, i.e. details related to manufacturing processes specially suited for touch sensitive devices
• CPC Class Codes: G06F 2203/04106 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 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 3/0412 Digitisers structurally integrated in a display
• 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
• CPC Class Codes: G06F 3/045 using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact
• CPC Class Codes: G09G 3/36 using liquid crystals
• CPC Class Codes: H03K 17/9622 using a plurality of detectors, e.g. keyboard
• CPC Class Codes: Y10T 29/43 Electric condenser making
• CPC Class Codes: Y10T 29/49105 Switch making

Abstract

A capacitive touch panel and a display device using the capacitive touch panel are provided. The capacitive touch panel includes a first electrode layer, a second electrode layer, and a dielectric layer disposed between two layers. The first electrode layer has a plurality of first A electrode strings and first B electrode strings extended along a first direction. The first A electrode string and the first B electrode string respectively has a plurality of first direction electrodes. The second electrode layer has a plurality of second direction electrodes connected in series along a second direction. The first A and B electrode strings are disconnected in the first electrode layer while they are simultaneously detected for presence of signal variation.

Claims

1. A capacitive touch panel comprising:

a first electrode layer having a first A electrode string and a first B electrode string distributed along a first direction, each of the first A electrode string and of the first B electrode string having a plurality of first direction electrodes respectively, wherein the first A electrode string and the first B electrode string are disconnected in the first electrode layer, the first A electrode string and the first B electrode string are simultaneously detected for presence of signal variation; and

a second electrode layer overlapping the first electrode layer and having a plurality of second direction electrodes connected in series and distributed along a second direction, wherein the second direction crosses the first direction.

2. The capacitive touch panel of claim 1, wherein the first A electrode string and the first B electrode string are collinear along the first direction.

3. The capacitive touch panel of claim 2, wherein the first electrode layer includes a plurality of parallel first A electrode strings in parallel and a plurality of corresponding first B electrode strings, the adjacent first A electrode strings have different amount of the first direction electrodes and thus the space between the first A electrode strings and the first B electrode strings has a distribution shape selected from a group of an indented shape, an oblique line shape and a trapezium shape.

4. The capacitive touch panel of claim 2, wherein the first electrode layer includes a plurality of parallel first A electrode strings and a plurality of corresponding first B electrode strings, the adjacent first A electrode strings have equal number of the first direction electrodes.

5. The capacitive touch panel of claim 2 further comprising a first linking pad and a second linking pad disposed outside of the first electrode layer, wherein a conducting wire is extended from a first end of the first electrode layer to couple the first A electrode string with the first linking pad, a conducting wire is extended from a second end of the first electrode layer to couple the first B electrode together with the second linking pad.

6. The capacitive touch panel of claim 2 further comprising a first linking pad disposed outside of the first electrode layer, wherein the first A electrode string couples with the first B electrode string via a conducting wire disposed outside of the first electrode layer and the conducting wire couples with the first linking pad.

7. The capacitive touch panel of claim 2, wherein a part of the adjacent second direction electrode strings couple in series to form a second A electrode string and another part of the adjacent second direction electrode strings couple in series to form a second B electrode string, wherein the second A electrode string and the second B electrode string are disconnected in the second electrode layer, the first A electrode string and the first B electrode string are simultaneously detected for presence of signal variation.

8. The capacitive touch panel of claim 7, wherein the second electrode layer includes a plurality of parallel second A electrode strings and a plurality of corresponding second B electrode strings, the adjacent second A electrode strings have different number of the first direction electrodes, the space between the second A electrode strings and the second B electrode strings has a distribution shape selected from a group of an indented shape, an oblique line shape and a trapezium shape.

9. The capacitive touch panel of claim 7, wherein the second electrode layer includes a plurality of parallel second A electrode strings and a plurality of corresponding second B electrode strings, the adjacent second A electrode strings have equal number of the second direction electrodes.

10. The capacitive touch panel of claim 7 further comprising a third linking pad and a fourth linking pad disposed outside of the second electrode layer, wherein a conducting wire is extended from a first end of the second electrode layer to couple the second A electrode string with the third linking pad, the second B electrode string couples with the fourth linking pad via a conducting wire extended from a second end of the second electrode layer.

11. The capacitive touch panel of claim 7 further comprising a third linking pad disposed outside of the second electrode layer, wherein the second A electrode string couples with the second B electrode string via a conducting wire disposed outside of the second electrode layer and the conducting wire couples with the third linking pad.

12. The capacitive touch panel of claim 1, wherein the first A electrode string and the first B electrode string are collinear in the first electrode layer.

13. The capacitive touch panel of claim 12 comprising a plurality of first A electrode strings and first B electrode strings disposed in parallel, wherein the first B electrode strings corresponding to the adjacent first A electrode strings are not adjacent to each other.

14. The capacitive touch panel of claim 12, wherein the second electrode layer has a second A electrode string and a second B electrode string distributed along the second direction, the second A electrode string and the second B electrode string have a plurality of second direction electrodes respectively, wherein the second A electrode string and the second B electrode string are disconnected in the second electrode layer, the second A electrode string and the second B electrode string are simultaneously detected for presence of signal variation.

15. The capacitive touch panel of claim 14, wherein the second A electrode string and the second B electrode string are disposed in parallel in the first electrode layer.

16. The capacitive touch panel of claim 15 comprising a plurality of the second A electrode strings and the second B electrode strings disposed in parallel, wherein the second B electrode strings corresponding to the adjacent second A electrode strings are not adjacent to each other.

17. A method of manufacturing the capacitive touch panels comprising:

forming a first electrode layer having a first A electrode string and a first B electrode string distributed along a first direction, the first A electrode string and the first B electrode string respectively having a plurality of first direction electrodes, wherein the first A electrode string and the first B electrode string are disconnected in the first electrode layer;

forming a second electrode layer to overlap the first electrode layer and to have a plurality of second direction electrodes connected in series and distributed along a second direction, wherein the second direction crosses the first direction; and

detecting for presence of signal variation in the first A electrode string and the first B electrode string.

18. The manufacture method of claim 17, wherein the step of forming the first electrode layer includes disposing the first A electrode string and the first B electrode string on the same row along the first direction.

19. The manufacture method of claim 18, wherein the step of forming the first electrode layer includes:

forming a plurality of parallel first A electrode strings and a plurality of corresponding first B electrode strings; and

disposing different number of the first direction electrodes on the adjacent first A electrode strings, wherein the space between the first A electrode strings and the first B electrode strings has a distribution shape selected from a group of an indented shape, an oblique shape and a trapezium.

20. The manufacture method of claim 18 further comprising:

forming a first linking pad and a second linking pad outside of the first electrode layer;

extending a conducting wire from a first end of the first electrode layer to couple the first A electrode string with the first linking pad; and

extending a conducting wire from a second end of the first electrode layer to couple the first B electrode string with the second linking pad.

21. The manufacture method of claim 18 further comprising:

forming a first linking pad outside of the first electrode layer;

coupling the first A electrode string with the first B electrode string via a conducting wire outside of the first electrode layer; and

coupling the conducting wire with the first linking pad.

22. The manufacture method of claim 18, wherein the step of forming the second electrode layer includes:

connecting a part of the adjacent second direction electrodes in series to form a second A electrode string;

connecting another part of the adjacent second direction electrodes to form a second B electrode strings, wherein the second A electrode string and the second B electrode string are disconnected in the second electrode layer; and

detecting for presence of signal variation at the second A electrode string and the second B electrode string simultaneously.

23. The manufacture method of claim 22, wherein the step of forming the second electrode layer includes:

forming a plurality of parallel second A electrode strings and a plurality of corresponding second B electrode strings; and

disposing different number of the second direction electrodes on the adjacent second A electrode strings, wherein the space between the second A electrode strings and the second B electrode strings has a distribution shape selected from a group of an indented shape, an oblique line shape and a trapezium shape.

24. The manufacture method of claim 22 further comprising:

disposing a third linking pad and a fourth linking pad outside of the second electrode layer;

extending a conducting wire from a first end of the second electrode layer to couple the second A electrode string with the third linking pad; and

extending a conducting wire from a second end of the second electrode layer to couple the second B electrode string with the fourth linking pad.

25. The manufacture method of claim 22 further comprising:

forming a third linking pad outside of the second electrode layer;

coupling the second A electrode string with the second B electrode string via a conducting wire disposed outside of the second electrode layer; and

coupling the conducting wire with the third linking pad.

26. The manufacture method of claim 17, wherein the step of forming the first electrode layer includes disposing the first A electrode string and the first B electrode in parallel.

27. The manufacture method of claim 26, wherein the step of forming the first electrode layer includes:

disposing the first A electrode strings and the B electrode strings in parallel; and

positioning the first B electrode strings corresponding to the adjacent first A electrode strings to be not adjacent to each other.

28. The manufacture method of claim 27 further comprising outputting a determination signal from a plurality of the first A electrode strings when a signal variation is detected at the adjacent first A electrode strings.

29. The manufacture method of claim 26, wherein the step of forming the second electrode layer includes:

disposing a second A electrode string and a second B electrode string along the second direction and thus the second A electrode string and the second B electrode string having a plurality of the second direction electrodes respectively, wherein the second A electrode string and the second B electrode string are disconnected in the second electrode layer; and

detecting for presence of signal variation in the second A electrode string and the second B electrode string simultaneously.

30. The manufacture method of claim 29, wherein the step of forming the first electrode layer includes:

disposing a plurality of the second A electrode strings and the second B electrode strings in parallel; and

positioning the second B electrode strings corresponding to the adjacent second A electrode strings to be not adjacent to each other.