Rotational position detecting device which compensates for eccentricity of rotating object

摘要

A rotational position detecting apparatus detects the rotational position of a rotating object and compensates for an eccentricity of the rotating object. First and second sensors generate first and second detection signals having phases offset relative to each other. An error signal denoting the eccentricity of the rotating object is generated in accordance with a fluctuation of an amplitude signal corresponding to a difference between amplitudes of the first and second detection signals. The error signal is added to a position signal to obtain a eccentricity compensated rotational position detection signal.