Lens hood assembly for zoom lens

A lens hood assembly for a zoom lens having an optical axis and having a group of variable power lenses for varying focal length, at least one lens of said group of lenses being moveable in the optical axis direction of the zoom lens, said assembly comprising a lens hood which is moveable in the optical axis direction of the zoom lens and which is provided with a center opening through which incident light passes into the zoom lens, said lens hood being secured for movement together with said moveable one of said lenses, whereby the lens hood is moved forwardly at a long focal length of the zoom lens and is moved rearwardly at a short focal length of the zoom lens, a plurality of moveable barrier elements which are supported on an incident light restriction wall secured to an annular frame member of the zoom lens to define a restricted incident opening with respect to the center opening of the lens hood in accordance with the focal length of the zoom lens and a motor driven cam ring for moving the variable power lenses of the zoom lens.

A lens hood assembly for a zoom lens having a group of variable power lenses for varying the focal length and comprising an outermost annular frame member, wherein said outermost annular frame is provided, on a front end, with an incident opening through which incident light passes into a zoom lens, and an incident light restriction wall which defines the incident opening, said incident light restriction wall having a plurality of movable barrier members thereon, said incident light restriction wall restricting the incident opening in accordance with the focal length of the zoom lens, said movable barrier members mounted for a movement to open and close said incident opening.

A lens hood assembly for a zoom lens having a group of variable power lenses for varying the focal length and comprising an outermost annular frame member, wherein said outermost annular frame member is provided, on a front end, with an incident opening through which incident light passes into a zoom lens, and an incident light restriction wall which defines the incident opening, said incident light restriction wall having a plurality of movable barrier elements thereon, said incident light restriction wall restricting the incident opening in accordance with the focal length of the zoom lens, said group of variable lenses comprising at least front and rear groups of lenses which are moved forwardly at a long focal length of the zoom lens so as to approach each other and are moved rearwardly at a short focal length so as to space themselves from each other, said movable barrier elements are associated with rotational movement of a cam ring, wherein the incident opening defined by the movable barrier elements is made smallest at the longest focal length of the zoom lens and is made largest at the shortest focal length of the zoom lens.

A lens hood assembly for a zoom lens having a group of variable power lenses for varying the focal length and comprising an outermost annular frame member, wherein said outermost annular frame member is provided, on a front end, with an incident opening through which incident light passes into a zoom lens, and an incident light restriction wall having a plurality of movable barrier elements thereon, said incident light restriction wall restricting the incident opening in accordance with the focal length of the zoom lens, said group of variable power lenses comprising at least front and rear groups of lenses which are moved forwardly at a long focal length of the zoom lens so as to approach each other and are moved rearwardly at a short focal length so as to space themselves from each other, there being two movable barrier elements, said two movable barrier elements being capable of linearly moving so as to move towards and away from each other, and a barrier closing and opening cam plate integrally rotate with a cam ring, for restricting the relative position of the movable barrier elements.

A lens hood assembly for a zoom lens having an optical axis and having a group of variable power lenses for varying focal length, at least one lens of said group of lenses being movable in the optical axis direction of a zoom lens, said assembly comprising a lens hood which is movable in the optical axis direction of the zoom lens and which is provided with a center opening through which incident light passes into the zoom lens, said lens hood being secured for movement together with said movable one of said lenses, whereby the lens hood is moved forwardly at a long focal length of the zoom lens and is moved rearwardly at a short focal length of the zoom lens, an incident light restricting wall having a central opening is provided on the front end of said lens hood, in front of a focusing lens of the zoom lens, said wall comprising means allowing incident light to pass into the zoom lens through said central opening.

A lens hood assembly for a zoom lens having a group of variable power lenses for varying focal length, at least one lens of said group of lenses being movable in the optical axis direction of a zoom lens, said assembly comprising a lens hood which is movable in the optical axis direction of the zoom lens and which is provided on the front end of said lens hood with an incident light restriction wall, said wall including a central opening comprising means allowing incident light to pass into the zoom lens, said lens hood being associated with the zooming operation of the zoom lens whereby the lens hood is moved forwardly at a long focal length of the zoom lens and is moved rearwardly at a short focal length of the zoom lens, said incident light restriction wall being positioned in front of a focusing lens of the zoom lens.