| 摘要 |
PURPOSE:To eliminate the need of providing a driving means for driving a driving mechanism provided in an image pickup optical system in the image pickup optical system and to eliminate the influence of vibration by the driving means and the unbalance of weight. CONSTITUTION:The rotational force of a driving motor 21 is transmitted to an axle drive guiding bar 33 through a gear train 23, so that a front moving lens group 112 is driven with the axle drive of the bar 33 to perform focusing. A clutch mechanism 51 is provided between the bar 33 and the lens group 42 and it is extended around the optical axis of the lens group 42. Thus, a motor for driving the lens group 42 need not be provided in the image pickup optical system and the vibration of the motor is eliminated and the unbalance of the weight in the lens group 42 is eliminated. |
