| 摘要 |
A shutter device includes a shutter base plate having a shutter aperture, a plurality of shutter blades, and an arm member arranged to swing on a predetermined shaft provided on the shutter base plate. The arm member is connected to each of the plurality of shutter blades to cause the shutter blades to travel over the shutter aperture when the arm member swings on the shaft. With a distance to the shaft from a connection part located farthest from the shaft among connection parts where the shutter blades are connected to the arm member assumed to be D, the dimension (length) of the shutter aperture in the direction of travel of the shutter blades assumed to be A, and the maximum angle of swing of the arm member assumed to be theta, at least one of the following conditions is satisfied:
|
