| 摘要 |
<p>Planetary gears (37) are rotatably supported at the rear end of a cam barrel (15). In the cam barrel (15) is formed a cam groove for moving a focus lens (2a, 2b) in the optical axis direction following rotation. The planetary gears (37) mesh with a gear section formed on the outer periphery at the front end section of an AF drive barrel (13) rotated by the drive of a motor and fixed by the stop of the motor. The planetary gears (37) also mesh with a gear section formed on the inner periphery at the front end section of an MF operation ring (19) for manual focus adjustment. The operation ring (19) is held by predetermined torque by a bar spring (41) and is rotatable at torque greater than the predetermined torque. When the drive barrel (13) is rotated by the motor and/or by manual operation of the operation ring (19), the cam barrel (15) is rotated in conjunction with the movement of the drive barrel (13) through the planetary gears (37), and this causes the focus lens (2a, 2b) to move in the optical axis direction.</p> |
