Patent ID: 7830756

Claim:
A method for obtaining a lens position of a lens in an optical disc system comprising the steps of: (A) generating a tracking error signal in response to a plurality of motion signals from an optical pickup unit of said optical disc system; (B) obtaining said lens position by demodulation from only the tracking error signal when starting motion of said lens by a tracking actuator, wherein a counter configured to count a number of half-tracks that said lens has crossed is set to zero and said lens position is determined by scaling an absolute value of the tracking error signal by a predefined scaling factor, wherein said half-tracks is half a distance of two neighboring tracks of an optical recording medium; (C) obtaining said lens position by demodulation from only the tracking error signal after motion of said lens has started, wherein a start of said motion is determined by an absolute value of said tracking error signal being greater than or equal to a threshold level and said lens position and a count of said counter are determined based upon a current value of the tracking error signal and a previous value of the tracking error signal; and (D) obtaining said lens position by demodulation from only the tracking error signal just before and after lens motion stops when said lens position is close to a target position, wherein said lens position is determined by scaling the tracking error signal by said predefined scaling factor and adjusting said count of said counter based upon the scaled value of the tracking error signal.