TWO LAYER CAPACITIVE SENSOR

• US 20130270095A1
• Filed: 04/11/2012
• Published: 10/17/2013
• Est. Priority Date: 04/11/2012
• Status: Active Grant

• Current Assignee: Synaptics Incorporated
• Original Assignee: Synaptics Incorporated
• Inventors: Tan, Yeh-Cheng, Yau, Tai-Wei
• Granted Patent: US 9,262,021 B2
• Time in Patent Office: Days
• US Class Current: 200/600
• CPC Class Codes: G06F 2203/04111 Cross over in capacitive digitiser, i.e. details of structures for connecting electrodes of the sensing pattern where the connections cross each other, e.g. bridge structures comprising an insulating layer, or vias through substrate
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• 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 3/0448 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: 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
• CPC Class Codes: Y10T 29/49105 Switch making

Abstract

The embodiments described herein provide improved sensor devices and methods that facilitate improved sensor devices. Specifically, the devices and methods provide capacitive image sensors that require only two layers of conductive elements formed on a single substrate. The ability to provide an image sensor using only a single substrate with two layers of conductive elements may substantially reduce the cost and complexity of the capacitive image sensor. In one embodiment, an input device is provided that comprises a first substrate having a first and second side. Each of the second array of second sensor electrodes comprises a plurality of isolated components disposed on the first side and a plurality of connectors disposed on the second side. The connectors and isolated components of the second sensor electrodes are arranged such that adjacent pairs of connectors along the first direction are separated by a distance substantially greater than the first pitch.

Claims

1. A capacitive input device comprising:

a first substrate having a first side and a second side;

a first array of first sensor electrodes disposed on the first side, each of the first array of first sensor electrodes having a first major axis aligned in a first direction;

a second array of second sensor electrodes, each of the second array of second sensor electrodes having a second major axis aligned in a second direction and a first pitch in the first direction, wherein each of the second array of second sensor electrodes comprises;

a plurality of isolated components disposed on the first side and a plurality of connectors disposed on the second side, each of the plurality of connectors ohmically coupling two of the plurality of isolated components along the second direction and through the first substrate to form the second array of second sensor electrodes; and

wherein an adjacent pair of connectors along the first direction are separated by a distance substantially greater than the first pitch.

2. The capacitive input device of claim 1 wherein the distance substantially greater than the first pitch is at least 1.5 times the first pitch.

3. The capacitive input device of claim 1 wherein each of the plurality of isolated components has a distal end located away from the second major axis of the second sensor electrode, and wherein each conductor is coupled to the distal end of two of the plurality of isolated components.

4. The capacitive input device of claim 1 further comprising an integrated circuit, the integrated circuit mounted on the second side and between the adjacent pair of connectors.

5. The capacitive input device of claim 4 wherein the integrated circuit is communicably coupled to the first array of first sensor electrodes and the second array of second sensor electrodes through the first substrate.

6. The capacitive input device of claim 4 wherein the integrated circuit is communicably coupled to the second array of second sensor electrodes through routing traces to the plurality of connectors.

7. The capacitive input device of claim 1 wherein the first substrate comprises a printed circuit board.

8. A capacitive input device comprising:

a first substrate having a first side and a second side;

a first array of first sensor electrodes disposed on the first side, each of the first array of first sensor electrodes having a first major axis aligned in a first direction;

a second array of second sensor electrodes, each of the second array of second sensor electrodes having a second major axis aligned in a second direction and a first pitch in the first direction, wherein each sensor electrode of the second array of second sensor electrodes comprises;

at least two isolated components disposed on the first side and at least one connector disposed on the second side, where the at least two isolated components are ohmically coupled together by the at least one connector to form the second sensor electrode,

and wherein a distance along the first direction between two adjacent connectors of two adjacent sensor electrodes of the second array of second sensor electrodes is at least 1.5 the first pitch.

9. The capacitive input device of claim 8 wherein each of the at least two isolated components has a distal end located away from the second major axis of a second sensor electrode, and wherein each conductor is coupled to the distal end of the at least two isolated components.

10. The capacitive input device of claim 8 further comprising an integrated circuit, the integrated circuit mounted on the second side and between the two adjacent connectors.

11. The capacitive input device of claim 10 wherein the integrated circuit is communicably coupled to the first array of first sensor electrodes and the second array of second sensor electrodes through the first substrate.

12. The capacitive input device of claim 10 wherein the integrated circuit is communicably coupled to the second array of second sensor electrodes through routing traces to the at least one connector.

13. The capacitive input device of claim 8 wherein the at least two isolated components are ohmically coupled to the at least one connector through vias in the first substrate.

14. A capacitive input device comprising:

a first printed circuit board (PCB) substrate having a first side and a second side;

a first array of first sensor electrodes disposed on the first side, each of the first array of first sensor electrodes having a first major axis aligned in a first direction;

a second array of second sensor electrodes, each of the second array of second sensor electrodes having a second major axis aligned in a second direction and a first pitch in the first direction; and

wherein;

a first sensor electrode in the second array of second sensor electrodes comprises;

at least four components disposed on the first side and at least two connectors disposed on the second side, where the at least four components are ohmically coupled together through the at least two connectors to define the first sensor electrode, and wherein the at least two connectors are disposed proximate distal ends of the at least four components; and

a second sensor electrode in the second array of second sensor electrodes, the second sensor electrode adjacent to the first sensor electrode, comprises;

at least four components disposed on the first side and at least two connectors disposed on the second side, where the at least four components are ohmically coupled together through the at least two connectors to define the second sensor electrode, and wherein the at least two connectors are disposed proximate distal ends of the at least four components such that each of the at least two connectors of the second sensor electrode are at distance of at least 1.5 times the first pitch from each of the at least two connectors in the first sensor electrode; and

an integrated circuit, the integrated circuit mounted on the second side and between the at least two connectors for the first sensor electrode and the at least two connectors for the second sensor electrode, the integrated circuit communicably coupled to the first array of first sensor electrodes and the second array of second sensor electrodes.

15. A method for forming a capacitive input device, the method comprising:

providing a first substrate having a first side and a second side;

forming a first array of first sensor electrodes on the first side, each of the first array of first sensor electrodes having a first major axis aligned in a first direction;

forming a plurality of isolated components, each of the isolated components part of a second array of second sensor electrodes where each of the second array of second sensor electrodes has a second major axis aligned in a second direction and a first pitch in the first direction, and

forming a plurality of connectors disposed on the second side, each of the plurality of connectors ohmically coupling two of the plurality of isolated components along the second direction and through the first substrate to form the second array of second sensor electrodes, wherein an adjacent pair of the plurality of connectors along the first direction are separated by a distance substantially greater than the first pitch.

16. The method of claim 15 wherein the distance substantially greater than the first pitch is at least 1.5 times the first pitch.

17. The method of claim 15 further comprising mounting an integrated circuit on the second side and between the adjacent pair of the plurality of connectors.

18. The method of claim 17 further comprising forming a communication coupling between the integrated circuit and the first array of first sensor electrodes and the second array of second sensor electrodes through the first substrate.

19. The method of claim 17 further comprising forming a communication coupling between the integrated circuit and the second array of second sensor electrodes through routing traces to the plurality of connectors.