Patent ID: 7508197

Claim:
An angular position sensor comprising: a rotating element; a non-rotating excitation element configured to emit a plurality of electromagnetic fields; and a non-rotating receiver element, said rotating element disposed in juxtaposition to said non-rotating excitation element and to said non-rotating signal receiver element, said plurality of electromagnetic fields produced by said non-rotating excitation element being electromagnetically coupled to said non-rotating receiver element through said rotating element, said non-rotating receiver element characterized in producing a single output signal in response to exposure to said plurality of electromagnetic fields, said rotating element characterized in that it varies the electromagnetic coupling of said plurality of electromagnetic fields between said non-rotating excitation element and said non-rotating receiver element as said rotating element rotates, wherein said non-rotating excitation element and said non-rotating receiver element are capacitively coupled, said rotating element comprising a first portion of dielectric material and at least a second portion of a material different from the dielectric material of the first portion, wherein said material of said second portion is a dielectric material different from the dielectric material of the first portion.