MULTIFUNCTIONAL TOUCH AND/OR PROXIMITY SENSOR

• US 20130050139A1
• Filed: 12/03/2010
• Published: 02/28/2013
• Est. Priority Date: 12/11/2009
• Status: Active Grant

• Current Assignee: Microchip Technology Germany GmbH (Microchip Technology Incorporated)
• Original Assignee: Andreas Gute
• Inventors: Gte, Andreas
• Granted Patent: US 9,525,416 B2
• Time in Patent Office: Days
• US Class Current: 345/174
• CPC Class Codes: G06F 1/1626 with a single-body enclosure integrating a flat display, e.g. Personal Digital Assistants [PDAs]
• CPC Class Codes: H03K 17/955 using a capacitive detector
• CPC Class Codes: H03K 17/962 Capacitive touch switches
• CPC Class Codes: H03K 2217/960765 Details of shielding arrangements
• CPC Class Codes: H03K 2217/96077 comprising an electrode which is floating
• CPC Class Codes: H03K 2217/960775 Emitter-receiver or "fringe" type detection, i.e. one or more field emitting electrodes and corresponding one or more receiving electrodes

Abstract

A sensor device has at least one first sensor element for detecting a touch and/or an approach, which is configured as a capacitive sensor element and which has a first electrode structure with a transmitting electrode and a reception electrode, wherein a first alternating electrical field emitted by the transmitting electrode may be coupled into the reception electrode,—at least one second sensor element, and—an evaluating device, which is coupled with the at least one first sensor element and with the at least one second sensor element, wherein the evaluating device is configured to evaluate a first signal tapped from the reception electrode of the first sensor element and at least one second signal provided by the second sensor element and to generate at least one detection signal dependent on the evaluation.

Claims

1. A sensor device, comprising

at least one first sensor element for the detection of a touch and/or an approach, which is configured as a capacitive sensor element and which comprises a first electrode structure, comprising a transmitting electrode and a reception electrode, wherein a first alternating electrical field emitted by the transmitting electrode is coupleable into the reception electrode,

at least one second sensor element, and

an evaluating device, which is coupled with the at least one first sensor element and with the at least one second sensor element, wherein the evaluating device is configured to evaluate a first signal tapped from the reception electrode of the first sensor element and at least one second signal provided by the second sensor element and to generate at least one detection signal dependent on the evaluation.

2. The sensor device according to claim 1, wherein the first electrode structure comprises a compensation electrode, wherein the evaluating device comprises a signal generator for supplying the transmitting electrode with a first alternating electrical signal and for supplying the compensation electrode with a second alternating electrical signal, wherein a second alternating electrical field emitted by the compensation electrode is coupleable into the reception electrode.

3. The sensor device according to claim 2, wherein the compensation electrode is arranged substantially between the transmitting electrode and the reception electrode.

4. The sensor device according to claim 2, wherein the second alternating electrical signal is dephased to the first alternating electrical signal.

5. The sensor device according to claim 2, wherein the first sensor element comprises a second electrode structure, wherein the second electrode structure comprises a number of field sensing electrodes, wherein the reception electrode, the transmitting electrode, the compensation electrode and the field sensing electrodes are arranged with respect to one another in such a way that

the first alternating electric field emitted by the transmitting electrode is also coupleable into at least one of the field sensing electrodes, and

the second alternating electric field emitted by the compensation electrode is coupleable substantially only into the reception electrode,

wherein the evaluating device is configured to evaluate a third signal tapped from at least one of the field sensing electrodes.

6. The sensor device according to claim 2, wherein the amplitude of the first alternating electrical signal is greater than an amplitude of a second alternating electrical signal.

7. The sensor device according to claim 1, wherein an approach of an object to the first electrode structure leads to a change in a level of the first signal tapped from the reception electrode, which is indicative for the approach of the object to the first electrode structure.

8. The sensor device according to claim 7, wherein an additional approach of the object to the second electrode structure leads to a change in a level of the at least one third signal tapped from the field sensing electrodes, wherein the level change of the third signal indicates that the object is approaching both the first electrode structure and the second electrode structure.

9. The sensor device according to claim 1, wherein at least one auxiliary electrode is assigned to one of the field sensing electrodes, wherein the auxiliary electrode is coupleable galvanically or capacitively with the at least one field sensing electrode.

10. The sensor device according to claim 5, wherein the third signals tapped from the field sensing electrodes are evaluated by a time-division multiplexing method.

11. The sensor device according to claim 1, wherein the second sensor element comprises at least one of position sensor, acceleration sensor, photosensor, and temperature sensor.

12. The sensor device according to claim 1, wherein the sensor device is configured to be arranged in an electric hand-held device.

13. A method for providing a detection signal, wherein

a first signal is tapped from a reception electrode of a first sensor element, wherein the first sensor element is configured as a capacitive sensor element and comprises a first electrode structure, which comprises a transmitting electrode and the reception electrode, wherein a first alternating electrical field emitted by the transmitting electrode is coupled into the reception electrode,

the first signal is evaluated,

a second signal is evaluated, which is provided by a second sensor element, and

a detection signal is generated, which depends on the evaluated first signal and on the evaluated second signal.

14. The method according to claim 13, wherein the first sensor element comprises a second electrode structure, which comprises a number of field sensing electrodes, wherein

the first alternating electric field emitted by the transmitting electrode is coupled into at least one field sensing electrode,

a third signal is tapped from at least one field sensing electrode, and

the third signal is evaluated,

wherein the detection signal depends on the evaluated third signal.

15. The method according to claim 14, wherein from the field sensing electrodes the third signal is tapped in a time-division multiplexing method.

16. The method according to claim 13, wherein the first electrode structure comprises a compensation electrode and wherein the transmitting electrode is supplied with a first alternating electrical signal and the compensation electrode is supplied with a second alternating electrical signal.

17. The method according to claim 14, wherein an auxiliary electrode is assigned to at least one of the field sensing electrodes, which is galvanically or capacitively coupleable with the field sensing electrodes.

18. The method according to claim 13, wherein the detection signal is indicative for the approach of a body to the first electrode structure and wherein in case of an approach of the body to the first electrode structure, which is arranged in an electric hand-held device, the electric hand-held device is switched from a first operating mode into a second operating mode.

19. The method according to claim 18, wherein the first operating mode is a sleeping mode and wherein the second operating mode is an active mode.

20. An electric hand-held device comprising a sensor device comprising

at least one first sensor element for the detection of a touch and/or an approach, which is configured as a capacitive sensor element and which comprises a first electrode structure, comprising a transmitting electrode and a reception electrode, wherein a first alternating electrical field emitted by the transmitting electrode is coupleable into the reception electrode,

at least one second sensor element, and

an evaluating device, which is coupled with the at least one first sensor element and with the at least one second sensor element, wherein the evaluating device is configured to evaluate a first signal tapped from the reception electrode of the first sensor element and at least one second signal provided by the second sensor element and to generate at least one detection signal dependent on the evaluation.

21. The electric hand-held device according to claim 20, wherein the electrodes of the first electrode structure are arranged in the hand-held device in such a way that, in case of an encompassing of the hand-held device by a hand, these are at least partially covered by the hand.

22. The electric hand-held device according to claim 20, wherein the electric hand-held device comprises at least one of mobile phone, input means for game console, mobile minicomputer, headphone, computer mouse, and remote control.