| 摘要 |
PROBLEM TO BE SOLVED: To obtain an excellent convergent beam characteristic and to perform high density recording/reproducing. SOLUTION: This device 1 is provided with a gonio-base positioning hole 9 opening in the optical axial direction of an optical path 6a for a reflection beam between a 45 deg. mirror 4 and an objective lens on an optical head base 5, and a spherical seat face 9a having a prescribed curvature is formed on the opening peripheral edge of this gonio-base positioning hole 9. Further, an optical axis tilt adjusting gonio-base 3 having a spherical surface 3a having the curvature suited to this spherical seat face 9a and a flat surface 3b placed on the reverse head base side of this spherical surface 3a is fitted, and the 45 deg. mirror 4 is fitted onto the flat surface 3b of this gonio-base 3. |
