Two-Dimensional Position Sensor
First Claim
1. A two-dimensional position sensor comprising a substrate with a sensitive area defined by a pattern of electrodes, the pattern of electrodes including drive electrodes and sense electrodes generally extending in a first direction, hereinafter the x-direction, and interleaved in a second direction, hereinafter the y-direction, wherein the sense electrodes comprise first, second and third groups of elements shaped such that adjacent ones of the elements of the first and second groups co-extend in the x-direction over a portion of the sensitive area and adjacent ones of the elements of the second and third groups co-extend in the x-direction over another portion, and wherein the drive electrodes are arranged to capacitively couple with the sense electrodes, wherein the sensor further comprises a controller comprising a drive unit for applying drive signals to the drive electrodes, and a sense unit for measuring sense signals received from each group of the sense electrodes representing a degree of capacitive coupling of the drive signals between the drive electrodes and each group of the sense electrodes.
13 Assignments
0 Petitions
Accused Products
Abstract
A two-dimensional position sensor is formed by drive electrodes (52) and sense electrodes (62, 64, 66) both extending in the x-direction and interleaved in the y-direction. The sense electrodes comprise several groups, two of which co-extend in the x-direction over each different portions of extent in the x-direction. The drive and sense electrodes are additionally arranged to capacitively couple with each other. In use, drive signals are applied to the drive electrodes and then the resultant sense signals received from the sense electrodes measured. The position of a touch or stylus actuation on the sensor is determined in the x- and y-directions as follows. In the x-direction, the position is determined by an interpolation between sense signals obtained from co-extending pairs of sense electrodes, and in the y-direction by interpolation between sense signals obtained from different sequences of drive signals applied to the drive electrodes.
-
Citations
14 Claims
- 1. A two-dimensional position sensor comprising a substrate with a sensitive area defined by a pattern of electrodes, the pattern of electrodes including drive electrodes and sense electrodes generally extending in a first direction, hereinafter the x-direction, and interleaved in a second direction, hereinafter the y-direction, wherein the sense electrodes comprise first, second and third groups of elements shaped such that adjacent ones of the elements of the first and second groups co-extend in the x-direction over a portion of the sensitive area and adjacent ones of the elements of the second and third groups co-extend in the x-direction over another portion, and wherein the drive electrodes are arranged to capacitively couple with the sense electrodes, wherein the sensor further comprises a controller comprising a drive unit for applying drive signals to the drive electrodes, and a sense unit for measuring sense signals received from each group of the sense electrodes representing a degree of capacitive coupling of the drive signals between the drive electrodes and each group of the sense electrodes.
-
14. A method of sensing position of an actuation on a sensitive area of a two-dimensional position sensor, the sensitive area being defined by a pattern of electrodes including drive electrodes and sense electrodes, both generally extending in a first direction, hereinafter the x-direction, and interleaved in a second direction, hereinafter the y-direction, wherein the sense electrodes comprise first, second and third groups of elements shaped such that adjacent ones of the elements of the first and second groups co-extend in the x-direction over a portion of the sensitive area and adjacent ones of the elements of the second and third groups co-extend in the x-direction over another portion, and wherein the drive electrodes are arranged to capacitively couple with the sense electrodes, the method comprising:
-
applying drive signals to the drive electrodes; measuring sense signals received from each group of the sense electrodes representing a degree of capacitive coupling of the drive signals between the drive electrodes and each group of the sense electrodes; determining position in the x-direction by an interpolation between sense signals obtained from co-extending pairs of groups of sense electrodes; and determining position in the y-direction by an interpolation between sense signals obtained by sequentially driving the drive electrodes with respective drive signals.
-
Specification