Asahi Kogaku Kogyo Kabushiki Kaisha

Pentax Corporation

Nikon Corporation

Asahi Seimitsu Kabushiki Kaisha

Asahi Kogaku Kogyo Kaisha

Takayuki Sensui

Isamu Hirai

Osamu Sato

Masato Yamamoto

Akio Takahashi

Toshimasa Yamanaka

Toshiyuki Kitazawa

Satoshi Nakano

Takenao Shishikura

Tetsuya Abe

Takayuki Ito

Koichi Maruyama

Moriyasu Shirayanagi

Makoto Iki

Tatsuhide Takebayashi

Toshiharu Takahashi

Hiroshi Kuboya

Teruaki Hiyamuta

Yasuo Nakamura

Sachio Hasushita

Makoto Mogamiya

Satoru Nakamura

Nobuhiko Matsudo

Chikara Yamamoto

Shinichi Suzuki

Tahei Morisawa

Shuji Yoneyama

Toshinori Take

Hirofumi Matsuo

Tatsuo Goto

Tatsuo Gotoh

Kazunori Komori

Hirofumi Matsuo, Deceased

An image-capturing lens has, in order from an object, an object side lens group Gand an image side lens group Gwhich is disposed next to the object side lens group Gwith an air space, and focusing is performed from a distant object to a close object by moving at least a part of the image side lens group Galong an optical axis as a focusing lens group, and image stabilization is performed by moving at least a part of the image side lens group Gas a shift lens group so as to have components roughly orthogonal to the optical axis.

Image capturing lens, optical apparatus having same, and method for manufacturing image-capturing lens

Providing a compact rear-focus optical system having excellent optical performance, an imaging apparatus, and a method for focusing the rear-focus optical system. The system includes, in order from an object, a first lens group Ghaving positive refractive power, an aperture stop S, and a second lens group G. At least a portion of the second lens group Gis movable along an optical axis of the rear-focus optical system upon focusing. Given conditional expressions are satisfied.

Rear-focus optical system, imaging apparatus and method for focusing the same

Providing a zoom lens system capable of obtaining higher optical performance, an imaging apparatus, and a method for varying a focal length of the zoom lens system. The system includes, in order from an object: a first lens group having negative refractive power; a second lens group having positive refractive power; a third lens group having negative refractive power; and a fourth lens group having positive refractive power. Upon zooming from a wide-angle end state to a telephoto end state, each lens group moves along an optical axis such that a distance between the first and second lens groups decreases, a distance between the second and third lens groups increases, and the distance between the third and fourth lens groups decreases; and the first lens group includes a negative lens, at least one lens in the negative lens includes an aspherical surface, and the negative lens satisfies given conditionals.

Zoom lens system, imaging apparatus and method for varying focal length

Providing a zoom lens system that has a high zoom ratio, high optical performance, and compactness, and is easy to be manufactured. The zoom lens system includes, in order from an object, a first lens group having positive refractive power, a second lens group having negative refractive power, a third lens group having positive refractive power, and a fourth lens group having positive refractive power. Zooming from a wide-angle end state to a telephoto end state is carried out by moving each lens group along the optical axis such that a distance between the first lens group and the second lens group increases, a distance between the second lens group and the third lens group decreases, a distance between the third lens group and the fourth lens group decreases. A zoom ratio is 5.0 or more. Given conditional expressions are satisfied.

Zoom lens system

Providing an interchangeable lens capable of carrying out quick focus from infinity to a close object with a magnification of almost life size by a light-weight moving lens group, exhibiting excellent imaging performance across an entire focusing range, and obtaining excellent imaging performance by a vibration reduction lens and its drive system appropriately arranged even upon vibration reduction. The lens includes a first group having positive power, a second group having negative power, a third group having positive power, and a fourth group having negative power. The fourth group includes a front group having negative power and a rear group having positive power. When the lens is vibrated, the lens corrects image blur by shifting the front group almost perpendicularly to an optical axis. When focusing from infinity to a close object, the first and the front groups are fixed and at least the third group is moved toward the object side.

Interchangeable lens

A stereo camera includes a pair of photographing optical systems arranged in a common plane so that a common photographing coverage occurs between a pair of photographing areas taken by the pair of photographing optical systems, an object distance measuring device, a convergence angle adjustment mechanism adapted to vary an angle of convergence defined by, and between, the optical axes of the pair of photographing optical systems, so as to adjust an amount of common photographic coverage of the pair of photographing optical systems, and a controller adapted to control the convergence angle adjustment mechanism in accordance with object distance data obtained by the object distance measuring device.

Stereo camera

A super-wide zoom lens system having sufficient zoom ratio and a high speed, capable of obtaining high optical performance. The system includes at least, in order from an object, a first lens group Ghaving negative refractive power, and a second lens group Ghaving positive refractive power. When zooming from a wide-angle end state to a telephoto end state, a distance between the first lens group Gand the second lens group Gvaries. The first lens group Gincludes at least one negative lens element and a glass material constructing at least one negative lens element (SL) in the first group Gsatisfies given conditions.

A zoom lens system includes at least two lens groups, and a negative first lens group is positioned at the most object-side of the zoom lens system. The negative first lens group includes a negative sub-lens group and a positive sub-lens group. The positive sub-lens group includes a positive lens element and a rearmost lens element of the negative first lens group. The rearmost lens element includes a plastic lens element having at least one aspherical surface.

An internal indicator of a viewfinder of a camera includes a viewfinder optical system which includes a focusing screen on which an object image is formed through a photographic optical system of the camera; at least one optical deflector that is positioned on or in the close vicinity of the focusing screen and is provided with at least one deflecting surface; and at least two light emitters for illuminating the optical deflector from the outside of the viewfinder optical system, which emit at least two light beams of different colors to be incident on the optical deflector.

Internal indication of a viewfinder of a camera

Wide-angle lens system

A focus detection device is provided with a pupil dividing system, an intensity distribution pattern forming system, a plurality of light receiving elements arranged in a direction where the pupil is divided, a focus detection area defining system having an focus detection opening, the focus detection area defining system being arranged on or in the vicinity of a plane equivalent to a focal plane of the photographing lens, the light passing through the pair of focus detection areas passing through the focus detection opening, a deflection prism arranged between the focus detection opening and the pupil dividing system, and an optical element provided in the vicinity of the pupil dividing system, the optical element having an anamorphic refractive power. A refractive power in the pupil dividing direction is greater than a refractive power in a direction perpendicular to the pupil dividing direction.

Focus detection device

A focus detection apparatus includes a pupil dividing device for dividing an exit pupil of an objective lens into separate areas, a field mask located at a position substantially optically equivalent to an image forming position of the objective lens, a condenser lens located in the vicinity of the field mask to make the exit pupil conjugate with the pupil dividing device, a light quantity distribution forming device for receiving light transmitted through the separate areas and forming light quantity distribution portions wherein the relative position of the light quantity distribution portions varies in accordance with a focus state of the objective lens, and a focus detection apparatus having at least one group of photoelectric transducers which receive the light quantity distributed by the pupil dividing device. The condenser lens is moved in accordance with the position of the exit pupil of the objective lens.

Focus detection apparatus

A soft-focus lens system includes a master lens group and a soft-focus lens group. The soft-focus lens group includes a positive sub lens group and a negative sub lens group. The positive sub lens group and the negative sub lens group are moved to set the normal photographing mode or the soft-focus photographing mode. Each of the sub lens groups is arranged to move with respect to the master lens group and the other of the sub lens groups so that the focal point and the focal length are not substantially varied before and after the switching of the soft-focus photographing mode to the normal photographing mode or vice versa.

Soft-focus lens system

Growing community of inventors

Tokyo, Japan

Takayuki Sensui