| 摘要 |
PROBLEM TO BE SOLVED: To provide a motor-controlled shutter device for controlling whether or not it is necessary to move a small diaphragm plate beforehand, lessening an operational load on a motor, and also, preventing the occurrence of troubles of exposure due to a mechanical bound at setting the small diaphragm plate, by operating the motor in a direction different from a sector operating direction. SOLUTION: In the case an object is bright, as for the small diaphragm plate 3 equipped with a diaphragm aperture 3a whose diameter is smaller than that of a previously formed shutter aperture 2, by moving the motor M in the direction different from the direction of operating two sectors, the plate 3 is controlled so as to occupy a position (a 1st position A) in the shutter aperture 2. And also, in the case of using the shutter aperture 2 as a diaphragm in the case the object is comparatively dark, it is necessary only to move the motor M in the direction of operating two sectors, it is not necessary to operate the small diaphragm plate 3. Thus, the device is not affected by the mechanical bound at setting the small diaphragm plate 3, and also, the operational load applied on the motor M is lessened. |
