Patent ID: 7758261

Claim:
A light amount adjustment apparatus, comprising: a light amount adjustment member configured to be operated in a predetermined direction to adjust the amount of light transmitted through a lens group; a rotatable magnet formed in a disk shape; a driving arm configured to be pivoted by rotation of said magnet to operate said light amount adjustment member; a core having a pair of confronting portions positioned so as to sandwich said magnet from an outer circumference side and a connecting portion configured to connect end portions of said confronting portions to each other; a coil through which one of said confronting portions of said core extends; and a base member having said core attached to said base member and supporting said magnet for rotation on said base member, said base member having a plurality of attaching projections provided at least at two places of said base member for attaching said core to said base member, and said attaching projections having a small projection for fitting with said core, and said attaching projections include first and second sandwiching portions configured to sandwich said core between said first and second sandwiching portions.