A driving apparatus includes a magnet that is magnetized to at least two poles in a circumferential direction and fixed to a rotor axis formed with a soft magnetic material, and first and second coils arranged in the same direction as the magnet with respect to the magnet-axis direction and arranged adjacent to an end surface of the magnet in the magnet-axis direction. The first magnetic pole portion is excited by energizing the first coil, and the second magnetic pole portion is excited to a pole opposite to the first magnetic pole portion by energizing the second coil. A yoke portion is formed with a soft magnetic material for supporting the first and second magnetic pole portions. The first magnetic pole portion includes a first coil insertion portion that is inserted to an internal diameter portion of the first coil, and a first magnet facing portion that is arranged to face a magnetized outer circumferential portion of the magnet with a predetermined gap at a predetermined angle. The second magnetic pole portion includes a second coil insertion portion that is inserted to an internal diameter portion of the second coil, and a second magnet facing portion that is arranged to face a magnetized outer circumferential portion of the magnet with a predetermined gap at a predetermined angle.

 
Web www.patentalert.com

> Driving device and light amount controller

~ 00395