Nikon Corporation

Kazumitsu Takezawa

Hitoshi Imanari

Hideo Kanno

Hiroshi Okano

Yoshiharu Shiokama

Shinichi Ushio

Norikatsu Konno

A shading device employed in a lens barrel having a plurality of lens groups includes a plurality of substantially tubular shading members provided between a first lens group and a second lens group that move relative to each other along the optical axis and overlap each other along the optical axis so as to allow the shading device to achieve a telescopic function.

Shading device and lens barrel

A position detecting device is used with a lens barrel that includes an optical system, an optical system driving member that moves at least part of the optical system, and a driving force transmitting member that transmits rotational driving force from a driving source to the optical system driving member. The position detecting device includes a linear moving member that converts rotational motion of the driving force transmitting member into a linear motion, and a detector that detects the linear movement of the linear moving member. This arrangement is capable of providing a very compact structure. The driving force transmitting member can be a rotating shaft-like member that rotates through at least one rotation. The position detecting device also can include a backlash eliminating member (e.g., a spring) that eliminates a backlash between the driving force transmitting member and the linear moving member.

Lens barrel position detecting device and method

A lens barrel including an iris stop unit which is easily secured in the lens barrel. The lens barrel includes a lens group holding frame fixed by screws to a moving tube which holds a lens group in a manner freely slidable in a forward or backward direction. A support ring is formed integrally with the moving tube, and the support ring, along with blades and a drive ring forms an iris stop unit. The blades and the drive ring are set at a designated position and the lens group holding frame is inserted into the moving tube and connected by screws. The drive ring is held by the front end of the lens group holding frame.

Lens barrel having an iris stop unit

There is disclosed a lens barrel which comprises a supporting frame for supporting lens groups, a cam barrel to be rotated around the optical axis to move the supporting frame in the direction of the optical axis in a predetermined range, a manual focusing ring to which the operator supplies a manual power, a manual power transmission mechanism to be moved by the manual power supplied to the manual focusing ring to rotate the cam barrel, a first limitation member for inhibiting the power transmission from the manual focusing ring to the cam barrel by limiting the movement of the manual power transmission mechanism when the supporting frame is moved to a vicinity of one end of the predetermined range by the rotation of the cam barrel, a motor power transmission mechanism for transmitting the motive power supplied from the motor to the cam barrel so as to rotate the cam barrel, and a second limitation member for limiting the rotation of the cam barrel, wherein the second limitation member is provided at a position for limiting the rotation of the cam barrel at the same time as or after the first limitation member limits the movement of the manual power transmission mechanism while the supporting frame is moving toward one end of the predetermined range.

Lens barrel

In a lens barrel which drives a focusing optical system using only one set of a cam groove and a cam pin engaged with the cam groove, the cam groove and the cam pin jointly defining a zooming operation and a focusing operation of the focusing optical system, to increase an automatic focusing speed, there is provided with a manual driving section rotated around an optical axis, an automatic driving section rotated around the optical axis and a rotation straight advance converting section for driving the focusing optical system after converting the rotational motion of the manual driving section or the automatic driving section into a straight advance motion by using only set of the cam groove and the cam pin for jointly defining the zooming and focusing operations of the focusing optical system. The manual driving section, the automatic driving section and the rotation straight advance converting section are interlocked with one another. A power transmitting member for directly transmitting power from the automatic driving section to the rotation straight advance converting section without passing this through the manual driving section is provided.

Lens barrel with interlocking key

A position detecting device comprises a pattern member having conductive patterns arranged in plural tracks; a slidable member having plural sliding pieces capable of sliding on the conductive patterns, wherein each of the sliding pieces assumes either a conductive state in contact with one of the conductive patterns or a non-conductive state not in contact with the conductive pattern; a signal processing device for detecting sets of the conductive patterns and the sliding pieces in conductive state, by transmitting electrical signals through the conductive patterns and the sliding pieces; and a discriminating device for identifying the relative position between the conductive patterns and the sliding pieces when the the conductive patterns and the sliding pieces in conductive state are detected at least a predetermined number of times or over at least a predetermined period of time.

Position detecting device

A lens barrel which has a lens holding member for holding a lens unit, a movement cam mechanism for moving the lens holding member in an optical-axis direction, a biasing member for biasing the lens holding member to shift a slide allowance of the movement cam mechanism in one direction, a biasing force receiving member for receiving a biasing force of the biasing member and a biasing force adjustment cam mechanism for moving the biasing force receiving member in the optical-axis direction so that the biasing force of the biasing member remains the same.

Growing community of inventors

Yokohama, Japan

Kazumitsu Takezawa