Lens actuator for dual lens optical disk apparatus having lens mounting base stopper and selected lens sensor

摘要

A lens actuator for use in an optical data reader, comprising: a base on which a plurality of N (N=natural number not less than two) objective lenses corresponding to N optical data recording media having substrates of different thicknesses, respectively are mounted; a supporting shaft which is provided on the base such that the base is movable vertically and rotatable within predetermined ranges, respectively relative to the supporting shaft; a pair of driving coils for performing changeover among the objective lenses and tracking follow-up of the data recording media; and N pairs of magnets which form a magnetic circuit together with the driving coils such that the base is rotated by the driving coils and the magnets.