Patent ID: 6014361
Filing Date: 2000-01-11
Classification: G11B

Abstract:
An optical head device, comprising:a semiconductor laser for emitting an elliptical light beam;a first optical element for converting the light beam emitted from the semiconductor laser into collimated light having an elliptic beam shape;shaping means for shaping the beam shape of the collimated light from an ellipse to a circle, the shaping means being an optical element having functions of: changing a direction of incident light so that an optical axis of an exiting light is perpendicular to an optical axis of the incident light, and shaping the beam shape of the incident light; anda second optical element for directing the collimated light having the beam shape which has been shaped into a circle onto an optical information recording medium, whereinthe semiconductor laser is located so that a short axis direction of the ellipse is substantially parallel to a rotation axis direction of the optical information recording medium.