| 摘要 |
PURPOSE:To facilitate the change of the arrangement relation between the polarization direction of a light beam by which a magneto-optical disk is irradiated and the direction of a track groove. CONSTITUTION:The laser beam having the polarization direction in the vertical direction exited from a semiconductor laser 1 is entered to a half wave length plate 11 to rotate the direction of the optical axis by 90 deg. and entered to a polarization beam splitter 2 as the laser beam having the direction of optical axis in the horizontal direction. The laser beam transmitted through the polarization beam splitter 2 is converged and emitted on the magneto-optical disk 6 through a collimating lens 3, start mirror 4 and objective lens 5. At this time, the polarization direction of the laser beam emitted on the magneto-optical disk 6 becomes the x-axial direction and the direction of the track groove 7 becomes the y-axial direction. When this polarization direction is changed to, e.g. y-axial direction, the half wavelength plate 11 is removed. |
