Canon Denshi Kabushiki Kaisha

Satoshi Kozu

Akira Fujita

Akira Kurosawa

Mitsuo Shibata

Naoki Kawakubo

The light-quantity control apparatus includes a base member, and a light-quantity control blade having a light-quantity control portion to control a quantity of light passing through a fixed aperture and a supported portion rotatably supported with respect to the base member. The light-quantity control portion and the supported portion of the light-quantity control blade are each rotated along a plane parallel to the aperture face, an intermediate portion thereof formed between the light-quantity control portion and the supported portion has a tilt with respect to the aperture plane toward the optical axis direction so that the light-quantity control portion is disposed distant from the supported portion in the optical axis direction. Thereby a concave space facing the fixed aperture is formed inside in the radial direction than the light-quantity control blade.

Light-quantity control apparatus and optical apparatus

The light-quantity control apparatus includes a stop blade including a stop portion and a supported portion rotatably supported with respect to a base member, a shutter blade having a shutter portion and a supported portion rotatably supported with respect to the base member, and a driving member disposed between the shutter and stop blades and rotating around the light-passing aperture to rotate the stop blade. The stop and shutter blades have tilts in their supported portions toward a same one side in the optical axis direction so that the stop and shutter portions are distant from the supported portions 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. A concave space facing the light-passing aperture is formed inside than the stop and shutter blades and the driving member.

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Tokyo, Japan

Satoshi Kozu