Patent ID: 8231235
Filing Date: 2012-07-31
Classification: G03B

Abstract:
1. A lens hood attaching/detaching mechanism for attaching a lens hood to a lens body by fixing and centering the lens hood, comprising: a hood-side mounting part that is provided on a part of the lens hood so as to be opposed to the lens body and serves as an attached part to the lens body; protrusion receiving portions provided on the hood-side mounting part; hood-side positioning portions provided on the hood-side mounting part; fixing convex portions formed on a surface of the hood-side mounting part so as to be opposed to the lens body; a body-side mounting part that is provided on a surface of the lens body so as to be opposed to the lens hood and serves as an attached part to the lens hood; protrusions that are provided on the body-side mounting part and are fit to the protrusion receiving portions upon attachment; body-side positioning portions provided on the body-side mounting part; introduction recessed portions that are provided on a surface of the body-side mounting part so as to be opposed to the lens hood and allow the fixing convex portions to be introduced into the introduction recessed portions upon attachment; and fixing uneven portions, each of which has a convex portion and a recessed portion continuously formed from the introduction recessed portion and has the fixing convex portion brought into contact with a positioning slope continuing to the recessed portion over the convex portion, when the lens hood is rotated relative to the lens body and is positioned by the hood-side positioning portions and the body-side positioning portions in a state in which the fixing convex portions are introduced into the introduction recessed portions upon attachment, the mechanism further comprising: a first body-side positioning portion as the body-side positioning portion; a first hood-side positioning portion as the hood-side positioning portion; a second body-side positioning portion having a phase difference relative to the first body-side positioning portion, at a rear in a rotation direction upon attachment and introduction; and a second hood-side positioning portion having a phase difference relative to the first hood-side positioning portion, at a rear in a rotation direction upon attachment and introduction, wherein the fixing convex portion is positioned in contact with the positioning slope also by the second body-side positioning portion and the second hood-side positioning portion.