Capacitive sensing in displacement type pointing devices
First Claim
Patent Images
1. A pointing device, comprising:
- a sense electrode structure comprising an arrangement of peripheral sense electrodes in a peripheral region surrounding a central sense electrode;
a displaceable member movable in an operational zone over the sense electrode structure and comprising a target electrode facing the sense electrodes and overlapping at least a respective portion of the central sense electrode in each position of the displaceable member in the operational zone; and
a measurement circuit coupled to the sense electrodes and operable to generate measurement values indicative of degrees of overlap between the target electrode and respective ones of the sense electrodes;
wherein in a given measurement cycle the measurement circuit is operable to generate a respective measurement value for each of the peripheral sense electrodes by applying a respective input signal across the corresponding peripheral sense electrode and the central sense electrode, each of the measurement values being indicative of a respective degree of overlap between the target electrode and the corresponding peripheral sense electrode.
3 Assignments
0 Petitions
Accused Products
Abstract
A pointing device includes a sense electrode structure and a displaceable member. The sense electrode structure includes an arrangement of peripheral sense electrodes in a peripheral region surrounding a central sense electrode. The displaceable member is movable in an operational zone over the sense electrode structure. The displaceable member includes a target electrode facing the sense electrodes and overlapping at least a respective portion of the central sense electrode in each position of the displaceable member in the operational zone.
-
Citations
21 Claims
-
1. A pointing device, comprising:
-
a sense electrode structure comprising an arrangement of peripheral sense electrodes in a peripheral region surrounding a central sense electrode; a displaceable member movable in an operational zone over the sense electrode structure and comprising a target electrode facing the sense electrodes and overlapping at least a respective portion of the central sense electrode in each position of the displaceable member in the operational zone; and a measurement circuit coupled to the sense electrodes and operable to generate measurement values indicative of degrees of overlap between the target electrode and respective ones of the sense electrodes; wherein in a given measurement cycle the measurement circuit is operable to generate a respective measurement value for each of the peripheral sense electrodes by applying a respective input signal across the corresponding peripheral sense electrode and the central sense electrode, each of the measurement values being indicative of a respective degree of overlap between the target electrode and the corresponding peripheral sense electrode. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19)
-
-
20. A pointing device, comprising:
-
a sense electrode structure comprising an arrangement of peripheral sense electrodes in a peripheral region surrounding a central sense electrode; and a displaceable member movable in an operational zone over the sense electrode structure and comprising a target electrode facing the sense electrodes and overlapping at least a respective portion of the central sense electrode in each position of the displaceable member in the operational zone; wherein the target electrode comprises a peripheral target electrode structure surrounding a central target electrode structure comprising a displaceable electrode that is movable towards and away from the sense electrode structure substantially independently of the surrounding peripheral target electrode structure; and wherein the central sense electrode completely overlaps the displaceable electrode in each position of the displaceable member in the operational zone.
-
-
21. A pointing device, comprising:
-
a sense electrode structure comprising an arrangement of peripheral sense electrodes in a peripheral region surrounding a central sense electrode; a displaceable member movable in an operational zone over the sense electrode structure and comprising a target electrode facing the sense electrodes and overlapping at least a respective portion of the central sense electrode in each position of the displaceable member in the operational zone; and a dielectric spacer between the target electrode and the sense electrode structure.
-
Specification