Patent ID: 7075317
Filing Date: 2006-07-11
Classification: G01D

Abstract:
1. A capacitive rotation angle sensor for measuring a small angle displacement of an object, comprising: an excitation array having a plurality of first emitters and a plurality of second emitters, the plurality of first emitters emitting a first sinusoidal signal, and the plurality of second emitters emitting a second sinusoidal signal, the second sinusoidal signal being out of phase with the first sinusoidal signal; a measurement array for measuring a position of the object arranged opposite to the excitation array and having a plurality of first detectors and a plurality of second detectors, the plurality of first detectors sensing a first voltage of the first sinusoidal signal and the second sinusoidal signal, and the plurality of second detectors sensing a second voltage of the first sinusoidal signal and the second sinusoidal signal; and an active rotor array which is adapted to be mechanically coupled to the object and rotationally moved between the excitation array and the measurement array, the active rotor array having a plurality of movable electrodes, wherein movement of the plurality of movable electrodes varies the first voltage and the second voltage sensed by the measurement array, wherein the capacitive rotation angle sensor measures a small angle displacement.