US 5,708,535 AGranted

Lens mirror cylinder having two movable lenses and a diaphragm unit

AssigneeSony Corporation

InventorsShinichi Orimo, Kenji Hirano, Toshifumi Takaoka, Kunio Nakazato, Ryosuke Tsuru

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Abstract

A lens mirror cylinder having first and second movable lens structures, constructed by assembling in a mirror cylinder a plurality of magnetic circuit means arranged on the outer periphery side of the second movable lens structure, guided so that it can move in the light axis direction of the lens, so as to face each other across the light axis, a first lens driving means for driving the first movable lens structure arranged at a position on the outer periphery side of the second movable lens structure in which the magnetic circuits are not arranged, and a lens diaphragm unit. By this construction, the space of the lens mirror cylinder can be effectively utilized, and a reduction of size of the lens mirror cylinder and the camera using the lens mirror cylinder is realized.

Claims21

Dependent claims

A lens mirror cylinder comprising:

a mirror cylinder provided with a lens guide means in a light axis direction;
a first movable lens structure comprising a first lens holder in which a first movable lens is installed and which is supported inside said mirror cylinder by the lens guide means, said first movable lens structure being freely movable in the light axis direction;
a second movable lens structure comprising a second lens holder in which a second movable lens is installed and which is supported inside said mirror cylinder by the lens guide means, said second movable lens structure being freely movable in the light axis direction;
a first lens driving means which has a drive source and a lens driving member connected to the first movable lens structure which is driven by the drive source to move the first movable lens structure in the light axis direction, said first lens driving means being installed in the mirror cylinder;
a diaphragm unit disposed in the mirror cylinder which comprises a diaphragm body with an adjustable aperture and a drive control unit driving this diaphragm body to control said aperture and which is installed in the mirror cylinder;
and
a second lens driving means comprising a linear motor comprised by a coil, a yoke comprised of an inside yoke piece penetrating through a center hole of said coil, an outside yoke piece extending to the outer periphery of the coil, and a base connecting base ends of said inside yoke piece and said outside yoke piece, and a magnet forming a closed magnetic path between said yoke pieces and the base, which is arranged inside the mirror cylinder, and which drives the second movable lens structure to move in the light axis direction, the second lens driving means further comprising a pair of yokes facing each other on two sides of the light axis while sandwiching the coil therebetween and, at the same time, the first lens driving means and the diaphragm unit being installed in the mirror cylinder while positioning the drive source and the drive control unit at positions orthogonal to the positions of arrangement of these yokes.

4 more elements

A lens mirror cylinder comprising:

a mirror cylinder provided with a lens guide means in a light axis direction;
a first movable lens structure comprising a first lens holder in which a first movable lens is installed and which is supported inside said mirror cylinder by the lens guide means, said first movable lens structure being freely movable in the light axis direction;
a second movable lens structure comprising a second lens holder in which a second movable lens is installed and which is supported inside said mirror cylinder by the lens guide means, said second movable lens structure being freely movable in the light axis direction;
a first lens driving means which has a drive source and a lens driving member connected to the first movable lens structure which is driven by the drive source to move the first movable lens structure in the light axis direction, said first lens driving means being installed in the mirror cylinder;
a diaphragm unit disposed in the mirror cylinder which comprises a diaphragm body with an adjustable aperture and a drive control unit driving this diaphragm body to control said aperture and which is installed in the mirror cylinder;
and
a second lens driving means which is constituted by arranging a plurality of magnetic circuits on an outer periphery of the second movable lens structure.

4 more elements

Dependencies are inferred from the claim text.