| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an exchange lens with a zooming function with good operability which is small sized and inexpensive, capable of easily changing operations between a manual mode and an electrical mode and executing an initializing action correctly and in a short time. <P>SOLUTION: The exchange lens, in the manual mode, carries out a zooming action by detecting travel of a first lens group by a manual operation and driving a second lens group by an actuator. The exchange lens, in the electrical mode, carries out a zooming action by driving a first lens group by the actuator, detecting the travel of the first lens group and driving the second lens group as well as setting a resetting position regarding the travel of the second lens group within a region outside the region in which the first lens group is capable of travelling in the optical axis direction and within the region in which the second lens group is capable of being travelled in the optical axis direction. <P>COPYRIGHT: (C)2013,JPO&INPIT |
