Capacitive controller and sensor

• US 9,916,052 B2
• Filed: 12/01/2015
• Issued: 03/13/2018
• Est. Priority Date: 01/07/2011
• Status: Active Grant

• Current Assignee: eGalax_eMPIA Technology Inc.
• Original Assignee: eGalax_eMPIA Technology Inc.
• Inventors: Lee, Cheng-Han
• Primary Examiner(s): Mehmood, Jennifer
• Assistant Examiner(s): NEUPANE, KRISHNA P.
• Application Number:
  US14/955,474
• Publication Number:
  US 20160085340A1
• Time in Patent Office: 833 Days
• Field of Search: None
• CPC Class Codes: G06F 2203/04104 Multi-touch detection in digitiser, i.e. details about the simultaneous detection of a plurality of touching locations, e.g. multiple fingers or pen and finger
• 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 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: G06F 3/04164 Connections between sensors and controllers, e.g. routing lines between electrodes and connection pads
• CPC Class Codes: G06F 3/04166 Details of scanning methods, e.g. sampling time, grouping of sub areas or time sharing with display driving Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally G06F3/04184
• CPC Class Codes: G06F 3/04186 Touch location disambiguation
• 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 3/047 using sets of wires, e.g. crossed wires
• CPC Class Codes: H03K 17/962 Capacitive touch switches
• CPC Class Codes: H03K 17/9622 using a plurality of detectors, e.g. keyboard
• CPC Class Codes: H03K 2017/9602 characterised by the type or shape of the sensing electrodes

Abstract

The present invention provides a capacitive controller for detecting at least one detecting plate and at least one reference plate surrounding each detecting plate. All of the reference plates are electrically coupled to the same first wire, and each reference plate is electrically coupled to a second wire. When an electrical signal is provided to the first wire and each second wire, one or more detecting plates touched or approached can be detected simultaneously based on the signal difference between each second wire and the first wire.

Claims

1. A capacitive controller, executing:

providing the same electrical signal to a first wire and each of at least one second wire directly connected to the capacitive controller, wherein all of at least one reference plate are electrically coupled to the first wire, and each of at least one detecting plate is electrically coupled to one of the at least one second wire; and

comparing a first signal difference with a second signal difference between a signal of one of the at least one second wire and a signal of the first wire so as to determine if the detecting plate electrically coupled to the second wire corresponding to the second signal difference is touched or approached by an external object, wherein the first signal difference is a difference between the signal of the first wire and a signal of one of the at least one second wire not touched or approached by any external object.

2. The capacitive controller of claim 1, wherein the at least one reference plate defines a space in which the detecting plate resides, and the at least one reference plate defines an opening through which a corresponding second wire is electrically coupled to the detecting plate.

3. The capacitive controller of claim 2, wherein the space is defined by a single reference plate.

4. The capacitive controller of claim 1, wherein the second wire corresponding to the first signal difference is the same as the second wire corresponding to the second signal difference, and the first signal difference and the second signal difference are detected asynchronously.

5. The capacitive controller of claim 1, wherein further executing:

determining the first signal difference if the first signal difference is within a predetermined range because no external object touches or approaches the detecting plate electrically coupled to the second wire corresponding to the first signal difference.

6. The capacitive controller of claim 1, wherein the detecting plate corresponding to the second signal difference is touched or approached by an external object if a difference between the first signal difference and the second signal difference is positive, and the detecting plate corresponding to the second signal difference is not touched or approached by any external object if a difference between the first signal difference and the second signal difference is negative.

7. The capacitive controller of claim 1, wherein a shielding line surrounds the first wire and each second wire.

8. The capacitive controller of claim 1, wherein the area of a side of each detecting plate facing towards a touch-sensitive sensor is smaller than that of opposite side, wherein the area of the side facing the touch-sensitive sensor and the area of the opposite side can be areas in a range with the same width between the two sides.

9. The capacitive controller of claim 1, wherein the dimension of each detecting plate is equal or approximately equal the total dimension of all of the reference plates.

10. The capacitive controller of claim 1, wherein the second wire corresponding to the first signal difference is different from the second wire corresponding to the second signal difference, and the first signal difference and the second signal difference are detected synchronously or asynchronously.

11. A capacitive sensor, comprising:

a first wire;

at least one second wire;

at least one reference plate for defining at least one space, and all of the reference plates being electrically coupled to the first wire;

at least one detecting plate, each of which residing in one of the at least one space and being electrically coupled to one of the at least one second wire; and

a controller for providing the same electrical signal to the first wire and each second wire directly connected to the capacitive controller, and comparing a first signal difference with a second signal difference between a signal of one of the at least one second wire and a signal of the first wire so as to determine if the detecting plate electrically coupled to the second wire corresponding to the second signal difference is touched or approached by an external object, wherein the first signal difference is a difference between the signal of the first wire and a signal of one of the at least one second wire not touched or approached by any external object.

12. The capacitive sensor of claim 11, wherein the at least one reference plate defines a space in which the detecting plate resides, and the at least one reference plate defines an opening through which a corresponding second wire is electrically coupled to the detecting plate.

13. The capacitive sensor of claim 12, wherein the space is defined by a single reference plate.

14. The capacitive sensor of claim 11, wherein the second wire corresponding to the first signal difference is the same as the second wire corresponding to the second signal difference, and the first signal difference and the second signal difference are detected asynchronously.

15. The capacitive sensor of claim 11, wherein the controller determines the first signal difference if the first signal difference is within a predetermined range because no external object touches or approaches the detecting plate electrically coupled to the second wire corresponding to the first signal difference.

16. The capacitive sensor of claim 11, wherein the detecting plate corresponding to the second signal difference is touched or approached by an external object if a difference between the first signal difference and the second signal difference is positive, and the detecting plate corresponding to the second signal difference is not touched or approached by any external object if a difference between the first signal difference and the second signal difference is negative.

17. The capacitive sensor of claim 11, wherein a shielding line surrounds the first wire and each second wire.

18. The capacitive sensor of claim 11, wherein the area of a side of each detecting plate facing towards a touch-sensitive sensor is smaller than that of opposite side, wherein the area of the side facing the touch-sensitive sensor and the area of the opposite side can be areas in a range with the same width between the two sides.

19. The capacitive sensor of claim 11, wherein the dimension of each detecting plate is equal or approximately equal the total dimension of all of the reference plates.

20. The capacitive sensor of claim sensor 11, wherein the second wire corresponding to the first signal difference is different from the second wire corresponding to the second signal difference, and the first signal difference and the second signal difference are detected synchronously or asynchronously.