| 摘要 |
PURPOSE:To require no special driving device for the movement of a mirror unit by moving a freely movable mirror moving device. CONSTITUTION:A lens unit 1 is held by a lens holder 6 and provided on a lens carriage 2, it is guided by a guide rail 3 and can be moved in the optical axis direction (y), and the lens holder 6 is mounted on the lens carriage 2 slidably in the longitudinal direction, i.e., in the direction (x) perpendicular to the optical axis. A rod-shaped guide rail 24 is penetrated at the end section of a mirror unit 20 assembled with the fourth mirror 21 and the fifth mirror 22, and the mirror unit 20 is made freely movable in the optical axis direction of the scanning light. The mirror unit 20 is freely moved by utilizing the movement of the lens moving means of the lens unit 1. No device is required at all for the movement of the mirror unit 20. |
