Patent ID: 8049738

Claim:
A touch sensitive position sensor comprising: a substrate defining a touch sensitive platform: a first resistive bus-bar on the substrate; a second resistive bus-bar substantially parallel to the first resistive bus-bar on the substrate; a third resistive bus-bar substantially parallel to the first resistive bus-bar and the second resistive bus-bar on the substrate, the third resistive bus-bar being between the first resistive bus-bar and the second resistive bus-bar; wherein the first resistive bus-bar extends between a first and a second electrode, the second resistive bus-bar extends between a third and a fourth electrode, and the third resistive bus-bar extends between a fifth and a sixth electrode; a first, second, third, fourth, fifth, and sixth drive channel associated with respective ones of the first, second, third, fourth, fifth, and sixth electrodes; each drive channel being operable to generate an output signal dependent on the resistance between the respective first, second, third, fourth, fifth, and sixth electrode and a position of an object; an anisotropic conductive area having a non-zero resistance arranged between the first, second and third resistive bus-bars such that currents induced in the anisotropic conductive area flow preferentially towards the first, second, and third resistive bus-bars; and a processor operable to generate an estimate for the position of the object by comparing the output signals from the fifth and sixth drive channels and a sum of the output signals selected from one of the first and second drive channels or the third and fourth drive channels; wherein processor is configured to estimate the position of the object in a first direction running between the resistive bus-bars from a ratiometric analysis of a sum of the output signals from the fifth and sixth drive channels and the sum of the selected output signals.