Patent ID: 8783977

Claim:
A light-quantity control apparatus provided with a light-passing aperture, comprising: a base member; a stop blade including a stop portion to change a quantity of light passing through the light-passing aperture and a stop blade-supported portion rotatably supported with respect to the base member; a shutter blade having a shutter portion to block the light passing through the light-passing aperture and a shutter blade-supported portion rotatably supported with respect to the base member; and a driving member disposed between the shutter blade and the stop blade and rotating with respect to the base member around the light-passing aperture to rotate the stop blade, wherein, when a direction orthogonal to an aperture plane of the light-passing aperture is defined as an optical axis direction, and a direction orthogonal to the optical axis direction is defined as a radial direction, the stop blade and the shutter blade respectively have tilts in the stop blade-supported portion and the shutter blade-supported portion toward a same one side in the optical axis direction with respect to the aperture plane so that the stop portion and the shutter portion are respectively distant from the stop blade-supported portion and the shutter blade-supported portion in the optical axis direction, the driving member has a shape concave toward the one side from its outer circumferential side portion to its inner circumferential side portion, and thereby a concave space facing the light-passing aperture is formed inside in the radial direction than the stop blade, the shutter blade and the driving member.