SENSOR APPARATUS AND METHOD FOR GENERATING SIGNALS INDICATIVE OF THE POSITION OR CHANGE IN POSITION OF LIMBS

• US 20100063421A1
• Filed: 04/28/2008
• Published: 03/11/2010
• Est. Priority Date: 04/26/2007
• Status: Active Grant

• Current Assignee: Neodrón Limited (Atlantic IP Services Limited)
• Original Assignee: Microchip Technology Germany GmbH (Microchip Technology Incorporated)
• Inventors: Ivanov, Artem
• Granted Patent: US 8,345,015 B2
• Time in Patent Office: Days
• US Class Current: 600/595
• CPC Class Codes: G06F 3/038 Control and interface arrangements therefor, e.g. drivers or device-embedded control circuitry
• CPC Class Codes: G06F 3/0383 Signal control means within the pointing device

Abstract

The invention relates to a sensor apparatus and to a method for generating electronic signals which indicate a spatial position and/or the movement of limbs, particularly the hand of a user relative to the sensor apparatus. These electronic signals can then be used for carrying out input processes in data processing, communication and other electrical devices. The object of the invention is to create solutions by which signals indicative of the position and/or the movement of limbs can be generated in a particularly advantageous manner. This object is achieved by a sensor apparatus for generating electrical signals which indicate the position or movement of limbs relative to a reference area, the apparatus comprising a transmitter electrode apparatus, a voltage generator for applying an alternating voltage to the transmitter electrode, a first receiver electrode apparatus, a second receiver electrode apparatus, and a third receiver electrode apparatus, wherein the first, second, and third receiver electrode apparatuses are each connected to high-impedance tapping systems. The first, second, and third receiver electrode apparatuses are preferably each connected to high-impedance inputs of an impedance transformer system, wherein information indicative of a location or movement is obtained on the basis of differences between the electrical events present at the outputs of the respective impedance transformer.

Claims

1. A sensor apparatus for generating electrical signals which indicate the position or movement of limbs relative to a reference area, the apparatus comprising:

a transmitter electrode apparatus,

a voltage generator for applying an alternating voltage to the transmitter electrode apparatus,

a first receiver electrode apparatus,

a second receiver electrode apparatus, and

a third receiver electrode apparatus, and

wherein the first, second, and third receiver electrode apparatuses are each connected to high-impedance tapping systems.

2. The sensor apparatus according to claim 1 wherein the first, second, and third receiver electrode apparatuses are each connected to high-impedance inputs of an impedance transformer system, and information indicative of a location or movement is obtained on the basis of differences between the electrical events present at the outputs of the respective impedance transformer.

3. The sensor apparatus according to claim 1 wherein a composite signal is formed, which represents the sum of voltages present at the receiver electrodes.

4. The sensor apparatus according to claim 1 wherein this composite signal is available at the respective impedance transformer system.

5. The sensor apparatus according to claim 1 wherein a synchronous detector is provided, which supplies signals indicative of the synchronicity of the output signal at the respective impedance transformer system, particularly of the voltage level and/or the phase compared to the exciting voltage.

6. The sensor apparatus according to claim 1 wherein the information indicative of a location or movement is obtained on the basis of differences between the electrical events present at the outputs of the respective synchronous detector.

7. The sensor apparatus according to claim 1 wherein the receiver electrodes are disposed symmetrically around the transmitter electrode apparatus.

8. The sensor apparatus according to claim 1 wherein the transmitter electrode is supplied by a generator with alternating current and produces a surrounding.

9. The sensor apparatus according to claim 1 wherein the receiver electrodes are disposed symmetrically around the transmitter electrode.

10. The sensor apparatus according to claim 1 wherein the voltage present at the receiver electrodes contains information about the distribution of the field of the transmitter electrode.

11. The sensor apparatus according to claim 1 wherein the voltages present at the receiver electrodes are present at the receiver electrodes of channels 1, 2, and 3.

12. The sensor apparatus according to claim 1 wherein the receiver electrodes are connected to the high-impedance inputs of the impedance transformers so as not to interfere with the electrical field of the transmitter electrode.

13. The sensor apparatus according to claim 1 wherein a mean value is formed from the respective signals downstream of the impedance transformer.

14. The sensor apparatus according to claim 1 wherein for each channel furthermore the difference between the signal thereof and the mean value is amplified:

Δ

K1, Δ

K2, and Δ

K3 are formed.

15. The sensor apparatus according to claim 1 wherein the mean value is amplified.

16. The sensor apparatus according to claim 1 wherein the amplified signals are used to obtain the amplitude using a synchronous detector, the amplitude is then digitized by an ADC and forwarded to a microcontroller for evaluation.

17. The sensor apparatus according to claim 1 wherein a diode rectifier is used instead of the synchronous detector.

18. The sensor apparatus according to claim 1 wherein a peak detector is used instead of the synchronous detector.

19. The sensor apparatus according to claim 1 wherein the ADC directly digitizes the alternating current.

20. A method for generating electrical signals that indicate the position or movement of limbs relative to a reference area, the method comprising the steps of

applying an alternating electrical field to a transmitter electrode apparatus, and tapping voltage events by at least three receiver electrodes disposed in the vicinity of the transmitter electrode apparatus, these voltage events being tapped at high impedance and the transmitter electrode apparatus extending within a triangular area defined by the transmitter electrodes.