Patent attributes
An optical head by which a good detection signal can be obtained based on a zeroth-order diffracted beam and first-order diffracted beams is provided. The optical head includes: a shaping element for shaping a beam emitted from a light source; a converging element for converging the beam that has been shaped by the shaping element on an optical recoding medium; and a detector for detecting an electric signal based on a zeroth-order diffracted beam and a first-order diffracted beam contained in the beam that has been reflected by the optical recoding medium. The shaping element is provided in a swingable manner so that a distance between a spot position at which the zeroth-order diffracted beam is incident on the detector and a spot position at which the first-order diffracted beam is incident on the detector can be adjusted.
