A rotary plate (6) has an eccentric shaft (6b) and a recessed portion (9) which are spaced from a rotary shaft (6a). A shutter (3) is connected to the eccentric shaft (6b) by a swing arm (7) which is rotatable about the eccentric shaft (6b). A pin (8) is provided on the swing arm (7). When the rotary plate (6) starts rotating from a closed condition of the shutter (3), the swing arm (7) moves linearly to release the shutter (3) even when the shutter (3) freezes to the casing (2). When the swing arm (7) further rotates, the pin (8) engages with the recessed portion (9) of the rotary plate (6). The swing arm (7) is integrated with the rotary plate (6). The shutter (3) is quickly opened. When the shutter (3) is fully opened, the pin (8) disengages from the recessed portion (9). As the eccentric shaft (6b) is located adjacent to the rotary shaft (6a), a large force is transmitted to the shutter (3). Thus, it becomes possible to use a low-power motor (4) to release the shutter (3) from the camera casing (2) even when they freeze together.