| 摘要 |
PROBLEM TO BE SOLVED: To enable the highly accurate mounting operation by positionally adjusting a reflection type optical element in the direction parallel with an optical axis of the incident luminous flux while allowing the flat side surface orthogonally crossed with the reflecting surface of the reflection type optical element to be in the state where it is energized from an opening part to the mounting surface, and adjustment the inclination in the manner of rotating it at the intersection with the incident optical axis. SOLUTION: An adjustment device 150 is constituted in such a manner that a start mirror 31 is engaged and held with an engaging part of the tip part so as movable and rotatable in the directions T and R. Also, the adjustment device 150 is made easily accessible to the mounting position of the start mirror 31 on a side plate 302 from a chamfer 320 of an arm tip part 300. The position and the inclination are adjusted by the adjustment device 150 by moving the start mirror 31 in the horizontal direction T and rotating it in the direction R along the optical axis. After this adjustment, the start mirror 31 is adhered and fixed to the side plate 302 by an adhering means of the adjustment device 150. Thus, a spot excellent in the optical performance is formable on an optical disk from a floating optical unit. |
