Cut-off mechanism of an optical module and optical module including such a mechanism

The mechanism (5) has a housing (100), and a driving motor including armature resistance and arranged to cause movement of a light beam cutoff shield, where the housing is made of a plastic material and the armature resistance lies between 25 and 120 Ohms. A pinion of the motor drives the cutoff shield through a gear, where a rotational angle of the shield is lower than a rotational angle of the pinion. The shield includes a tilted portion with respect to a foreground in a rotation according to an axis parallel with a rotational axis of the shield.