An optical disc recording/reproduction apparatus for recording and/or
reproducing a data by applying a beam from an optical head unit through a
substrate onto/from a recording layer of the optical disc through,
wherein the substrate of the optical disc is 0.3 mm or below; the optical
head unit comprises: an objective lens for converging an incident beam
and emitting the beam toward the optical disc; a forward lens for
converging the beam introduced through the objective lens and applying
the beam to the optical disc; a lens holder where the objective lens and
the forward lens are fixed; and an actuator for driving the objective
lens and the forward lens as a unitary block and controlling at least
focusing, the objective lens and the forward lens having a total
numerical aperture of 0.8 or above.