Patent ID: 6738324
Filing Date: 2004-05-18
Classification: G11B

Abstract:
A recording and/or reproduction apparatus for an information medium including a substrate having concave and convex portions and a plurality of recording layers, the recording and/or reproduction apparatus comprising:a light source for emitting a light beam; an optical system for diffracting the light beam emitted by the light source so as to output a first diffracted light beam and a plurality of second diffracted light beams; and a driving section for driving the optical system, wherein: the optical system outputs the first diffracted light beam and the plurality of second diffracted light beams, such that when one of the plurality of second diffracted light beams is converged to and reflected by one of the concave and convex portions, the first diffracted light beam is converged to one of the plurality of recording layers, and the driving section drives the optical system, such that the one of the plurality of second diffracted light beams is converged to the one of the concave and convex portions.