Abstract: A lens barrel capable of shortening its full length includes a photo-taking optical system with a rear unit lens and a front unit lens, a rear unit lens holding cylinder holding the rear unit lens, a front unit lens holding cylinder holding the front unit lens and movable in the direction of an optical axis relative to the rear unit lens between a photographing position for making the photo-taking optical system capable of photographing with the rear unit lens and a full length shortening position for shortening the full length of the lens barrel in the direction of the optical axis and a fixing member for fixing the front unit lens holding cylinder in one of the aforementioned positions relative to the rear unit lens holding cylinder.

Abstract: A diaphragm movement device that moves a diaphragm mechanism with movement of a lens group to improve optical performance is disclosed. The diaphragm movement device includes a first lens group, a second lens group that is movable in the direction of the optical axis with the respect to the first lens group for focus and/or focal length adjustment, a diaphragm mechanism including a diaphragm blade holding ring, a diaphragm driving plate, and a diaphragm blade between the first lens group and the second lens group, and a diaphragm movement component having a protrusion and a sloped surface. An applied force member moves the diaphragm mechanism in the direction of the optical axis by a fixed amount corresponding to the movement of the second lens group in the direction of the optical axis.

Abstract: A lens barrel has a movable lens unit movable in an optical-axis direction, a lens moving member for moving the movable lens unit and a frictional force applying member for applying a frictional force on the lens moving member so that a quantity of force for operating the lens moving member remains the same irrespective of a magnitude of the moving force for moving the movable lens unit.

Abstract: An auto-focusing device adapted for use with a camera. The device includes an auto-focusing optical system having a lens barrel anchoring section, a support member and a drive unit for causing the auto-focusing optical system to be moved into a desired position. The drive unit causes the auto-focusing optical system to be moved along a plane containing the optical axis of the auto-focusing optical system. The support member supports the auto-focusing device in the camera. The device also includes an energizing member which eliminates extraneous movement of the auto-focusing optical system. The energizing member has particular energizing characteristics and is positioned between the lens barrel anchoring section and the support member.

Abstract: A waterproof operation mechanism of an interchangeable lens barrel having an operation member which is rotatably set around a periphery of the interchangeable lens barrel. A button engages with the operation member such that the button penetrates the operation member and protrudes outward from the operation member. The button functions to fix the operation member at a predetermined rotation position and to release the operation member from the predetermined rotation position. The interchangeable lens barrel includes a knurled part around its periphery, the knurled part being made of an elastic material and having a protruding portion integrally formed therewith to cover the button. Further, the operation member includes a fitting groove on a periphery of the operation member to prevent the knurled part from being displaced in a direction of an optical axis of the lens barrel.

Abstract: A lens barrel which can be easily switched between a manual focusing mode and an auto-focusing mode employs a motor as a drive power source for driving a switching apparatus for switching between an auto-focusing apparatus and a manual focusing apparatus. When a photographer supplies an external electrical signal, a switching operation from the auto-focusing apparatus to the manual focusing apparatus and vice versa can be performed in accordance with the forward/reverse rotational direction of the motor.

Abstract: An electric connecting apparatus for a camera system in which a photographic lens is mounted to a camera body by angular attachment movement through a specified range, comprises, on each of the lens and the body, a movable contact unit and a relatively fixed contact unit. The contact units of each of the lens and the body extend circumferentially over a total angular range that exceeds the attachment movement angle. The contact units of the lens are disposed to avoid interference with portions of the camera body and the contact units of the camera body are disposed to avoid interference with portions of the lens during mounting of the lens.

Abstract: A focusing control apparatus comprises a focusing information detector for detecting focusing control information regarding a focusing lens and an auxiliary lens set position detector for detecting a set position of an auxiliary lens such as a soft focus lens. A stored correction coefficient for the set position of the auxiliary lens is utilized, together with the focusing control information, in determining a drive distance of the focusing lens to achieve proper focusing. In one modification, if the auxiliary lens is manipulated and the set position thereof is changed after an in-focus state is attained in a single mode, the above process is repeated. In another modification, if the auxiliary lens is manipulated after the in-focus state is attained in the single mode, the mode is switched to a continuous mode.

Abstract: A helicoid threaded tube formed by molding a synthetic resin in a split mold, comprises: a hollow cylindrical member of synthetic resin; primary threads integrally formed with the cylindrical member and helically extending on the inner or outer surface thereof and having a cross section which is substantially trapezoidal at all portions thereof except split line segments thereof where the matching surfaces of the split mold intersect with the cylindrical member; and relief thread portions centered at the split line segments and continuously extending from the primary threads with the width gradually narrowing, the relief thread portions having a height substantially equal to that of the primary threads. In such threaded tube, at those portions of its threads (relief portions) within which molding burrs will tend to occur during molding, the threads have a gradually narrowing width and a constant height.

Abstract: A diaphragm device in which the aperture of a diaphragm opening is variable from a minimum aperture to a fully open aperture comprises:a plurality of diaphragm blades each having a pivot center, the edge portion of the diaphargm opening being formed by an inner edge portion in which the diaphragm blades overlap one another; anda driving device for rotating the plurality of diaphragm blades about the pivot centers at a time;the inner edge portion including a first arc disposed in a first portion nearest to the pivot center and having a radius of curvature (r.sub.1) substantially equal to the fully open aperture, a second arc disposed in a second portion farther from the pivot center than the first portion and having a radius of curvature (r.sub.4) substantially equal to the minimum aperture, at least one-third arc disposed in a third portion farther from the pivot center than the second portion and having a radius of curvature (r.sub.3, r.sub.

Abstract: A zoom lens assembly comprises a photo-taking optical system having a focusing portion, a zooming portion, and an optic axis, a manual operator movable in the direction of the optic axis for zooming and rotatable about the optic axis for focusing, an electrically rotated drive shaft, a member for moving the zooming portion of the photo-taking optical system for zooming in response to the movement of the manual operator in the direction of the optic axis, an intermediate member rotatable in response to the rotation of the manual operator to move the focusing portion of the photo-taking optical system for focusing, and movable in the direction of the optic axis with the manual operator, a transmission system for coupling the intermediate member to the drive member for movement in the direction of the optic axis to thereby transmit the rotation of the drive member to the intermediate member irrespective of the movement of the intermediate member in the direction of the optic axis, and a change-over device operab

Abstract: A zoom lens assembly comprises an optical system containing lens units arranged on the optical axis, a stationary cylindrical member, and an operation member movable relative to the stationary cylindrical member. The operation member is moved in the direction along the optical axis for zooming and is rotated about the optical axis for focusing. The zoom lens assembly further comprises a lens holder axially movable relative to the stationary cylindrical member and holding a certain lens unit selected from the lens units and a cam member mounted axially movable along the optical axis and rotatable about the optical axis relative to the stationary cylindrical member.