ARRANGEMENT FOR PRODUCING AN ELECTRIC FIELD AND SENSOR DEVICE INCLUDING SAME

• US 20090321149A1
• Filed: 03/13/2007
• Published: 12/31/2009
• Est. Priority Date: 03/13/2006
• Status: Active Grant

• Current Assignee: Microchip Technology Germany GmbH (Microchip Technology Incorporated)
• Original Assignee: Microchip Technology Germany GmbH (Microchip Technology Incorporated)
• Inventors: Kaltner, Klaus
• Granted Patent: US 8,339,147 B2
• Time in Patent Office: Days
• US Class Current: 178/18.06
• CPC Class Codes: H03K 17/955 using a capacitive detector
• CPC Class Codes: H03K 2217/960755 Constructional details of capacitive touch and proximity switches

Abstract

The invention relates to an arrangement for producing an electric field which is markedly influenced in relation to the spatial expansion thereof, and to a sensor device which comprises the same. The aim of the invention is to provide solutions which make it possible to generate a quasi-static electric alternating field which expands in a precise manner in regard to focusing in a relevant preferential area embodied as a monitoring and signal transmission area. Said aim is achieved by means of a circuit arrangement comprising a field producing electrode device which is connected as such in an LC network and which is exposed to a spatial area of the field in such a manner that the capacity of the capacitor system comprising the electrode device alters in accordance with the dielectric properties of the material present in the spatial area of the field, an insulating layer which extends on a rear side of the field electrode device which is oriented away from the spatial area of the field, a screening electrode device which extends on the rear side of the insulating layer which is oriented away from the field electrode device and a field extinction electrode device which comprises an electrode surface which is oriented towards an extinction area. The field expansion electrode device and the field extinction electrode device are arranged in such a manner and impinged upon by voltage that the spatial area of the field and the extinction area are superimposed on each other in sections.

Claims

1. Circuit arrangement comprising:

a field generating electrode device which is incorporated into an LC-network and which is exposed toward a field space in such a manner that the capacitance of a condenser system which includes said field generating electrode varies in response of the dielectric properties of material present within said field space,

an insulator layer extending on a rear side of said field generating electrode device, and facing away from said field space,

a shield electrode device extending on a rear side of said insulating layer and facing away from said field space, and

a field extinction electrode device which comprises an electrode area facing toward an extinction area, wherein said the field generating electrode device and the field extinction electrode device are arranged in such a manner and subjected to electric voltage that the field space and the extinction space partially overlap each other.

2. Circuit arrangement according to claim 1 wherein the field extinction electrode device is arranged and driven in such a manner that an marginal zone of the field generated by the field generating electrode device and penetrating into the extinction field space is cut.

3. Circuit arrangement according to claim 1 wherein a separation electrode device is provided between the field generating electrode device and the field extinction electrode device.

4. Circuit arrangement according to claim 1 wherein the separation electrode device is received between two insulator material layers.

5. Circuit arrangement according to claim 1 wherein the separation electrode device is coupled with the shielding electrode device.

6. Circuit arrangement according to claim 1 wherein the separation electrode device is coupled directly with the shielding electrode device.

7. Circuit arrangement according to claim 1 wherein the a voltage is applied to field extinction electrode device with a phase-offset and with a higher level in respect to the voltage applied to the field generating electrode device.

8. Circuit arrangement according to claim 1 wherein the phase-offset is substantially π

and that the voltage has substantially the magnitude of the voltage applied to the field generating electrode.

9. Circuit arrangement according to claim 1 wherein the phase-offset is variable in adjustable manner.

10. Circuit arrangement according to claim 1 wherein the tension difference between the field generating electrode and the field extinction electrode is variable in adjustable manner.

11. Circuit arrangement according to claim 1 wherein the separation electrode device extends bar-like between the field generating electrode and the field extinction electrode.