Patent ID: 7266057
Filing Date: 2007-09-04
Classification: G11B

Abstract:
1. Method for generating a lens position signal, wherein the lens position signal describes the position of the optical axis of an objective lens of an apparatus for reading from and/or writing to an optical recording medium with regard to the optical axis of an optical scanner assigned to the objective lens, wherein primary and secondary scanning beams incident on adjacent tracks of the recording medium are generated and the primary and secondary scanning beams reflected from the recording medium are detected, and wherein a primary-beam error signal CPP and a secondary-beam error signal OPP are derived from the detected reflected primary and secondary scanning beams, wherein the lens position signal LCE is obtained from the primary-beam error signal CPP and the secondary-beam error signal OPP in accordance with the following relationship; wherein the weighting factor G is chosen in such a way that the following holds true: wherein Δx designates the distance between the secondary beams and the primary beam and p designates the track spacing of the optical recording medium.