Electrode of self-capacitive touch panel utilizing serpentine trace to increase resistance

• US 9,575,607 B2
• Filed: 02/13/2015
• Issued: 02/21/2017
• Est. Priority Date: 02/14/2014
• Status: Active Grant

• Current Assignee: Ili Technology Corp. (MediaTek, Inc.)
• Original Assignee: MStar Semiconductor Incorporated (MediaTek, Inc.)
• Inventors: Hung, Guo-Kiang, Chen, Chien-Chuan, Kuo, Chao-Yang
• Primary Examiner(s): Abdin, Shaheda
• Application Number:
  US14/622,357
• Publication Number:
  US 20150234497A1
• Time in Patent Office: 739 Days
• US Class Current: 1/1
• CPC Class Codes: G06F 3/044 by capacitive means
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• CPC Class Codes: G06F 3/0448 Details of the electrode shape, e.g. for enhancing the detection of touches, for generating specific electric field shapes, for enhancing display quality
• CPC Class Codes: H05K 1/11 Printed elements for providing electric connections to or between printed circuits
• CPC Class Codes: H05K 1/167 incorporating printed resistors
• CPC Class Codes: H05K 2201/09263 Meander
• CPC Class Codes: H05K 2201/09272 Layout details of angles or corners
• CPC Class Codes: H05K 2201/09281 Layout details of a single conductor meander H05K2201/09263; layout details of angles or corners H05K2201/09272
• CPC Class Codes: H05K 2201/09381 Shape of non-curved single flat metallic pad, land or exposed part thereof; Shape of electrode of leadless component notches in edge pads H05K2201/09181
• CPC Class Codes: H05K 2201/09418 Special orientation of pads, lands or terminals of component, e.g. radial or polygonal orientation
• CPC Class Codes: H05K 2201/097 Alternating conductors, e.g. alternating different shaped pads, twisted pairs; Alternating components
• CPC Class Codes: H05K 2201/10053 Switch

Abstract

An electrode of a self-capacitive touch panel is provided. The electrode, coupled to a control circuit of the self-capacitive touch panel via a conducting wire, includes: a serpentine portion, having a first side; a main portion, having a second side; and a connecting portion, connected to the first side and the second side to connect the serpentine portion and the main portion. A length of the connecting portion is smaller than a length of the first side and a length of the second side.

Claims

1. A flat electrode of a single layer self-capacitive touch panel, coupled to a control circuit of the self-capacitive touch panel, the flat electrode comprising:

a main portion;

a first serpentine portion, coupled to the main portion and coplanar with the main portion, comprising a serpentine trace; and

a second serpentine portion, directly connected to the main portion while not directly connected to the first serpentine portion,

wherein the first serpentine portion increases a resistance of the electrode corresponding to the control circuit through the serpentine trace.

2. The flat electrode of a single layer self-capacitive touch panel according to claim 1, wherein the first serpentine portion comprises a plurality of parallel sub-traces.

3. The flat electrode of a single layer self-capacitive touch panel according to claim 2, wherein widths of the sub-traces are substantially equal, and a total length of the sub-traces is associated with the resistance of the electrode corresponding to the control circuit.

4. The flat electrode of the single layer self-capacitive touch panel according to claim 2, wherein gaps between the sub-traces are substantially equal.

5. The flat electrode of the single layer self-capacitive touch panel according to claim 2, wherein the self-capacitive touch panel further comprises another electrode adjacent to the electrode and coupled to the control circuit, the another electrode comprises a second serpentine portion, and a height of the first serpentine portion is substantially equal to a height of the second serpentine portion.

6. The flat electrode of the single layer self-capacitive touch panel according to claim 5, wherein the second serpentine portion comprises a plurality of another parallel sub-traces, widths of the another sub-traces are substantially equal to the widths of the sub-traces, and gaps between the another sub-traces are substantially equal to the gaps between the sub-traces.

7. The flat electrode of the single layer self-capacitive touch panel according to claim 1, wherein the single layer self-capacitive touch panel comprises a capacitor, the resistance of the electrode and the capacitor form a low-pass filter (LPF), and a cut-off frequency of the low-pass filter (LPF) is determined by adjusting the resistance of the electrode to filter out surges.

8. A flat electrode of the single layer self-capacitive touch panel, coupled to a control circuit of the self-capacitive touch panel, the flat electrode comprising:

a serpentine portion, having a first side;

a main portion, coplanar with the serpentine portion and having a second side;

a connecting portion, connected to the first side and the second side to connect the serpentine portion and the main portion; and

a first serpentine trace, directly connected to the main portion while not directly connected to the serpentine portion,

wherein a length of the connecting portion is smaller than lengths of the first side and the second side.

9. The flat electrode of the single layer self-capacitive touch panel according to claim 8, wherein the first side and the second side are parallel.

10. The flat electrode of the single layer self-capacitive touch panel according to claim 8, wherein the serpentine portion comprises a second serpentine trace.

11. The flat electrode of the single layer self-capacitive touch panel according to claim 10, wherein the second serpentine trace comprises a plurality of sub-traces.

12. The flat electrode of the single layer self-capacitive touch panel according to claim 11, wherein widths of the sub-traces are substantially equal, and a total length of the sub-traces is associated with a resistance of the electrode corresponding to the control circuit.

13. The flat electrode of the single layer self-capacitive touch panel according to claim 11, wherein gaps between the sub-traces are substantially equal.

14. The flat electrode of the single layer self-capacitive touch panel according to claim 13, wherein the self-capacitive touch panel further comprises another electrode adjacent to the electrode and coupled to the control circuit of the self-capacitive touch panel, the another electrode comprises a third serpentine trace, and a height of the third serpentine trace is substantially equal to a height of the second serpentine trace.

15. The flat electrode of the single layer self-capacitive touch panel according to claim 14, wherein the third serpentine trace comprises a plurality of another sub-traces, widths of the another sub-traces are substantially equal to the width of the sub-traces, and gaps between the another sub-traces are substantially equal to gaps between the sub-traces.

16. The flat electrode of the single layer self-capacitive touch panel according to claim 8, wherein the single layer self-capacitive touch panel comprises a capacitor, a resistance of the electrode and the capacitor form an LPF, and a cut-off frequency of the low-pass filter (LPF) is determined by adjusting the resistance of the electrode to filter out surges.