Electrical drive device for bending photographing optical system

An electrical drive device for a bending photographing optical system, said bending photographing optical system including a movable optical element that is movable in an optical axis direction and a reflection optical element positioned on said optical axis, said electrical drive device comprising:

• a motor provided with a leadscrew which extends therefrom in a direction parallel to said optical axis and drives said movable optical element to move in a direction of said optical axis,
• wherein said leadscrew includes a threaded portion which screw-engages with a nut member provided on said movable optical element, and a small-diameter portion having a smaller diameter than that of said threaded portion, said small-diameter portion being positioned beside a side surface of said reflection optical element, and
• wherein part of said motor is positioned behind said reflection surface of said reflection optical element so that said motor overlaps said reflection surface as viewed in the direction of said optical axis.