| 摘要 |
When a stepping motor is used as a driving source for a shutter device, if the stepping motor loses synchronization because of variations in load during driving or the like, it becomes unable to rotate a driving ring at that time, and this disables an exposure operation. In a first zone where a driven member is driven, but a light shielding member remains in a closed state or an open state, the motor drives the driven member in open-loop driving mode. In a second zone where the driven member is driven, and thus the light shielding member moves to the closed state or the open state, the motor drives the driven member in feed-back driving mode. |
