An optical pickup of an optical disc apparatus has a lens holder for
holding an objective lens is pivoted with a guide shaft slidably in a
direction in parallel with an optical axis of the objective lens and
rotatably around the guide shaft in a direction perpendicular to the
optical axis. For focusing a laser beam on a data recording face of an
optical disc in a focusing on operation, a wobble signal of rectangular
waveform having a predetermined voltage and a predetermined frequency is
applied to a tracking coil for reciprocally displacing the lens holder in
the direction perpendicular to the optical axis, while a focusing coil is
driven for moving the lens holder in the direction in parallel with the
optical axis. Thus, the lens holder can be moved smoothly along the guide
shaft, so that the possibility of failure of the focusing the laser beam
on the optical disc can be reduced drastically.