| 摘要 |
PROBLEM TO BE SOLVED: To provide a structure suitable for miniaturization of a light amount adjustment device with a simple structure.SOLUTION: The light amount adjustment device has: a light amount adjustment part 3; and a blade driving member 2 that is rotatably held by a blade support part 1e of a base member 1, held rotatably in a circumferential direction of a light passage aperture by the base member 1 and rotates a light amount adjustment blade via a blade engagement part 2e. The blade driving member 2 is assembled to the base member 1 so that the blade engagement part 2e is arranged closer onto a stationary aperture 1a side than the blade support part 1e of the base member 1 from an opposite direction to a direction having a light amount adjustment blade 3 assembled to the base member 1 of an optical axis direction. A light amount adjustment blade 3 has a shape that has the light amount adjustment part 3 located away on one side of an optical axis direction with respect to a supported part so that a recessed space is formed closer onto the stationary aperture 1a side than the blade engagement part 2e. The base member 1 and the blade driving member 2 are arranged closer onto the recessed space than the light amount blade 3. |
