Nittoh Inc.

Nittoh Kogaku K.k.

Takuya Kageyama

Takashi Yamaguchi

Atsuro Yajima

A lens unit includes a display member that is in a cylindrical shape, that rotates around an optical axis of the lens unit, and that has a scale indicating a photographing distance on an outer circumference surface thereof, and a window member that is provided over the display member, that exposes part of the outer circumference surface including the scale of the display member, and that hides the other part of the outer circumference surface of the display member. The photographing distance has first and second length units. The display member is movable along the optical axis between a first position and a second position. When the display member is in the first positon, the window member exposes the first length unit. Further, when the display member is in the second position, the window member exposes the second length unit.

Lens unit

A circumferential angle adjustment device for a generatrix of a cylindrical lens, comprising: a lens holding tube which holds the cylindrical lens; an outer peripheral tube in which the lens holding tube is arranged on an inner peripheral side thereof; a cam member which is provided on an outer peripheral side of the lens holding tube and has a cam surface eccentric with respect to an axis intersecting with an optical axis of the lens holding tube, and a cam member engaging portion which is formed in the outer peripheral tube and engages with the cam member in the circumferential direction of the optical axis, wherein the lens holding tube is supported with respect to the outer peripheral tube in at least three directions at regular intervals in the circumferential direction of the optical axis.

Circumferential angle adjustment device for generatrix of cylindrical lens, and lens barrel equipped with circumferential angle adjustment device for generatrix of cylindrical lens

A zoom lens unit includes a zoom ring that has a scale indicating a focal length of the zoom lens unit, an indicator member that points a desired value on the scale, and a selection mechanism that is configured to select one of first and second moving states of the indicator member. In the first moving state, the indicator member moves as the zoom ring rotates. Further, in the second moving state, the indicator member moves without rotating the zoom ring.

Zoom lens unit and indicator member

An optical device includes a fixed tube that has a straight groove extending in a first direction parallel to an optical axis of the optical device, a cam ring that has a cam groove extending in a second direction intersecting to the first direction, a cam follower that is engaged with the straight groove and the cam groove, a lens unit that moves in conjunction with the cam follower in the first direction, and an auxiliary cam follower that is engaged with the straight groove and that is not engaged with the cam groove. When the fixed tube and the cam ring relatively rotate, the lens unit moves in the first direction. Further, the lens unit is fixed to the cam follower and the auxiliary cam follower.

Optical device

A lens holder includes an inner barrel for holding at least one lens, an outer barrel that is positioned outside the inner barrel and supports the inner barrel so that the inner barrel linearly slides along a central axis thereof across an inner surface of the outer barrel, and a cam barrel that rotates in a state where the cam barrel is coaxially disposed between the inner barrel and the outer barrel. The cam barrel includes at least two subunits of the same shape produced by dividing the cam barrel on a plane that includes the central axis, an operating part that passes through an operating slit provided on the outer barrel and moves at least one of the subunits to rotate the cam barrel, a helical cam mechanism that slides, via a driven part provided on the inner barrel, the inner barrel forward and backward along the central axis when the cam barrel rotates, and a locking mechanism for pulling at least one of the subunits onto the outer barrel to stop rotation of the cam barrel.

Lens holder and lens unit

A lens holder holds a plurality of lenses aligned in a direction of an optical axis. This lens holder is at least partially assembled from subunits divided on a plane that includes the optical axis. In a connecting shell that connects a first shell and a second shell and holds an optical element for bending an optical path, an optical path of only one subunit is effectively used. The connecting shell includes a first connecting structure for connecting to the first shell and second connecting structures for connecting to the second shell, the second connecting structures being disposed at two symmetrical positions around the first optical axis.

A lens holder for holding a plurality of lenses is provided. The lens holder is assembled from a plurality of subunits divided on a plane that is parallel to an optical axis. A subunit includes a substantially cylindrical outer shell and front side rear side portions that extend from an inner surface of the outer shell toward the optical axis to support at least one lens from in front and behind respectively. When the at least one lens is attached between the portions, one of the portions is harder to deform than the other of portions.

Growing community of inventors

Suwa, Japan

Takuya Kageyama