| 摘要 |
PROBLEM TO BE SOLVED: To make a lens drive unit compact while sufficiently maintaining driving force thereof. SOLUTION: In the voice coil type lens drive unit, a magnetic field generating means 14 for applying a radially distributed magnetic field on a driving coil 13 mounted on the outer peripheral side of a lens holder 12 is constituted by arranging four first circular-arc permanent magnets 14m and four second planar permanent magnets 14n having circumferential length shorter than that of the first permanent magnet 14m symmetrically with respect to an optical axis. Regarding the shape of a yoke 15, the part where the first permanent magnet 14m is assembled is formed to a circular-arc shape, and the part where the second permanent magnet 14n is assembled is formed to a planar shape. COPYRIGHT: (C)2008,JPO&INPIT
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