Lens driving device comprising magnetic circuit with high magnetic efficiency

摘要

A lens driving device includes a lens holder including a tubular portion for holding a lens assembly, a driving coil fixed to the lens holder so as to position around the tubular portion, and a yoke including a permanent magnet opposite to the driving coil. The yoke includes an outer hollow cylindrical portion having a rectangular cylindrical shape, the permanent magnet includes at least four permanent magnet pieces each having a rectangular cross section. Four magnetic circuit auxiliary members are disposed between four corners of the outer hollow cylindrical portion of the yoke and four ones of the permanent magnet pieces that are disposed at the four corners of the outer hollow cylindrical portion of the yoke.