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.

 
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> Semiconductor integrated circuit and burn-in test method thereof

~ 00439