PURPOSE: To output an actuating signal, by making an operating member moved by magnetic force of a permanent magnet contact with the permanent magnet when fitting has been released in accordance with turning of a coil in the magnetic field of the permanent magnet, in an electromagnetic driving shutter.

CONSTITUTION: A working lever 16 which is provided with an iron piece 18 of a soft magnetic substance tightly fixed to its end part, and is installed to a front plate 3 through an insulating material 17 is driven by a sector ring 6 by feeble spring force of a spring 20 in the vicinity of a turning start position of the sector ring 6, and after that, when the iron piece 18 enters the working range of a permanent magnet 1 by the timing immediately before the shutter becomes a pinhole, it is moved in the direction as indicated with an arrow, fitting of a stopper part 16a and the sector ring 6 is released, and the working lever 16 is attracted to the permanent magnet 1 by energizing force of the spring 20 and magnetic force operated on the iron piece of the permanent magnet 1. In this case, it is detected that the potential of the working lever 16 becomes the same as that of the permanent magnet 1 and the front plate 3.