| 摘要 |
PURPOSE:To prevent the shifting of an optical axis during focusing, by supporting an objective lens system at its gravity center position in an optical information reproducing device which has the objective lens system atop of an arm supported by a gimbals. CONSTITUTION:A frame 13 is coupled with the tip of an arm 3, springs 14 are provided on the upper and lower end surfaces of the frame 13, and an objective lens 15 is suspended through those springs 14. A cylindrical magnet 16 is fixed closely around the external circumference part of the lens bacrel of the objective lens 15. Further, a focusing coil 17 is provided around the external circumference of the cylindrical magnet 16. A fixed stanchion 20 fixed on a base at one end is fitted to a wire 19. Since the height-directional centers of the focusing coil 17 and cylindrical magnet 16 nearly coincide with the center of gravity of the objective lens 15, so no torsional force is produced at the objective lens 15 when the arm is in motion in the direction of tracking correction. |
