US Patent 7634189 Two-step auto-focusing camera

A two-step auto-focusing camera includes a lens unit (12); a permanent magnet (124) being fixedly mounted around the lens unit to move with the lens unit; first and second coil seats (14, 15) with first and second coils (145, 155) wound thereon being mounted around the lens unit at two opposite sides of the magnet. When electric currents are supplied to the first and second coils, one of the coil seats generates an attraction force to the lens unit, and the other coil seat generates a repulsion force to the lens unit. A flange (143, 153) extends outwardly from an outer periphery of each coil seat at an end near the magnet to limit the magnet to move between the flanges of the first and second coil seats during movement of the lens unit.