OPTICAL SCANNING APPARATUS FOR APPLIANCES FOR RECORDING OR REPRODUCING INFORMATION USING AN OPTICAL RECORDING MEDIUM

摘要

The invention provides an optical scanning apparatus for appliances for recording or reproducing information using an optical recording medium, said scanning apparatus automatically matching itself to the curvature of a curved recording medium or of a recording medium with axial runout without there being different wire diameters for the resilient support of the lens holder (LH) or other additional damping means or an additional control loop for this purpose. This object is achieved by virtue of an arrangement comprising coils and magnets being provided which has an asymmetrical magnetic field distribution which is provided for matching the orientation of a lens (L) in the optical scanning device to a curved recording medium or to any axial runout in the recording medium. The asymmetrical magnetic field distribution is achieved with magnets arranged offset laterally or with magnets (MS) which are bevelled on one side or with a focusing coil which is asymmetrically shaped or is arranged asymmetrically with respect to the magnets. The individual embodiments for achieving an asymmetrical magnetic field distribution can be combined with one another.