Olympus Optical Company, Ltd.

Olympus Imaging Corporation

Olympus Corporation

Akiyoshi Tochigi

Yasuharu Yamada

Masaru Morooka

Yasuji Ogata

Keiichi Kuba

Shinya Takahashi

Hisashi Goto

Kazuteru Kawamura

Yoichi Iba

Seiichiro Tabata

Masashi Hankawa

Yukihiko Sugita

Tetsuo Nagata

Eiji Shirota

Naoto Shimada

Toshiro Okamura

Hirohiko Kimata

Toshio Takahashi

Masami Takase

Keitaro Yokoyama

Yasutaka Kashiki

Yuki Tokuhashi

Takaaki Ue

Masato Yasugaki

Satoshi Imai

Teruhisa Mitsuo

A reflecting telescope optical system comprises, a main reflecting mirror, a sub reflecting mirror which is disposed at a position facing a reflecting surface of the main reflecting mirror, and a plurality of lens units which is disposed at a position facing a reflecting surface of the sub reflecting mirror. The reflecting surface of the main reflecting mirror is a concave surface, and a reflecting area is formed to be ring-shaped. The reflecting surface of the main reflecting mirror and the reflecting surface of the sub reflecting mirror are mutually facing. The first operation is a movement for focusing at an object positioned between infinity and a near position, and the second operation is a reciprocating movement for changing the focused state after focusing. An amount of movement in the first operation is larger than an amount of movement in the second operation.

Reflecting telescope optical system, optical unit, and image pickup apparatus using the same

A zoom lens comprising, in order from the object side to the image side a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, a third lens unit having a positive refractive power, a fourth lens unit having a negative refractive power, and a fifth lens unit having a positive refractive power, wherein the first lens unit is located closest to the object side, the fifth lens unit is located closest to the image side, during zooming from the wide angle end to the telephoto end, the first lens unit, the second lens unit, the third lens unit, and the fourth lens unit move, the fifth lens unit is stationary, and the distances between the lens units vary, the third lens includes a positive lens, and the zoom lens satisfies the following condition (1):72&#x3c;&#x3bd;&#x3c;110&#x2003;&#x2003;(1).

Zoom lens and image pickup apparatus equipped with same

An inner focus lens system includes from the object side, a first lens unit having a positive refractive power, an aperture stop, a second lens unit having a positive refractive power, and a third lens unit. The first lens unit includes a plurality of negative lenses and at least one positive lens, the lens located closest to the object side is a negative lens. The second lens unit includes at least one negative lens and at least one positive lens, and moves toward the object side for focusing from an infinite object distance to a close object distance such that the distance between the second lens unit and the aperture stop decreases and that the distance between the second lens unit and the third lens unit increases. The lens system satisfies the following conditions: 1&#x3c;f/f 14 (1), and 0.8&#x3c;f/f&#x3c;3 (2).

Inner focus lens system and image pickup apparatus using the same

A zoom lens comprising, in order from an object side thereof, a first lens group of positive refracting power, a second lens group of negative refracting power, an aperture stop, a third lens group of positive refracting power, a fourth lens group of negative refracting power, and a fifth lens group of positive refracting power. Upon zooming from the wide-angle end to the telephoto end, at least the first lens group and the aperture stop remain fixed in position, the second and third lens groups move in the optical axis direction, and the separation between each of the lens groups and the aperture stop changes. Upon focusing from a focusing-on-infinity state to a close-range-focusing state, the fourth lens group moves in the optical axis direction, with satisfaction of the following:&#x2212;0.36&#x3c;4/1&#x3c;&#x2212;0.05&#x2003;&#x2003;(1A),where fl and f4 are the focal lengths of the first and fourth lens groups, respectively.

Zoom lens and imaging apparatus incorporating the same

A two-unit zoom lens system which forms an image on an image pickup surface, includes in order from an object side to an image side, a first lens unit Ghaving a negative refracting power and a second lens unit Ghaving a positive refracting power. At the time of zooming from a wide angle end to a telephoto end, a distance between the first lens unit and the second lens unit is narrowed. The first lens unit includes in order from the object side to the image side, a first lens having a negative refracting power, a second lens having a negative refracting power, and a third lens having a positive refracting power, and the two-unit zoom lens system satisfies predetermined conditional expressions.

Two-unit zoom lens system and image pickup apparatus using the same

The invention relates to a focus detection optical system for digital single-lens reflex cameras or the like and an imaging apparatus incorporating the same. A pupil division optical system comprises an aperture stop having a pair of openings with an optical axis of said taking lens held between them, and a pair of re-imaging lenses, each consisting of a double-convex lens having a convex entrance-side surface and a convex exit-side surface. When, on a plane passing through the optical axis of the taking lens and the centers of gravity of the openings in the aperture stop, a surface apex is defined by a position of the convex entrance-side surface, and the convex exit-side surface, which position is extended most in a direction parallel with the optical axis of the taking lens, the surface apexes of the entrance-side surface and the exit-side surface of the double-convex lens are positioned away from the optical axis of the taking lens in the same direction, and the distance of the surface apex of the entrance-side surface from the optical axis of the taking lens is larger than the distance of the surface apex of the exit-side surface from the optical axis of the taking lens.

Focus detection optical system and imaging apparatus incorporating the same

The invention concerns an optical system adapted to split an optical path from a taking optical system into a finder optical system, which has a camera-shake correction function best suited for the finder optical system, and so on. This optical system comprises a taking optical system and a finder optical system. The taking optical system comprises an optical path splitter means operable to split an optical path into the finder optical system, and the finder optical system includes a relay optical system RLS for re-forming a subject image once. Anti-shake is implemented by shifting an optical subsystem RL that forms a part of the finder optical system in a plane vertical to an optical axis.

Optical system, finder optical system, relay type finder optical system, eyepiece optical system, and single-lens reflex camera

The invention relates to an imaging system equipped with an electronic viewfinder suitable for compactness and having a sufficient angle of viewing field and satisfactory optical performance, especially the ability to prevent harmful light. The imaging system comprises an image pickup optical system, an image pickup device for receiving a light beam guided by the image pickup optical system, an image display device for displaying an image thereon, a controller for converting image information obtained from the image pickup device into signals capable of being displayed on the image display device, and a viewing optical system for guiding an image appearing on the image display device to a viewer's eye. The viewing optical system comprises, in order from an image display device side, one negative lens and one positive lens.

Imaging system

A zoom lens system comprises, in order from an object side, positive, negative, positive, negative, and positive refractive power lens groups, and while changing the magnification, the distance between the first lens group and the second lens group increases, the distance between the second lens group and the third lens group decreases, the distance between the third lens group and the fifth lens group increases, and the second lens group moves more towards the object side at the telephoto end than the wide-angle end.

Zoom lens and a camera providing the same

A finder optical system includes an eyepiece optical system with a positive refracting power. The eyepiece optical system includes an optical unit with a positive refracting power and a lens unit with a positive refracting power, In the eyepiece optical system, a refracting surface that is located most distant from an eyepoint of the eyepiece optical system has a positive refracting power and is configured as an aspherical surface with a negative refracting power on a periphery thereof.

Finder optical system

A real image mode finder optical system is constructed to be independent of a photographing optical system and includes, in order from the object side, an objective optical system with a positive refracting power, a field frame located in the proximity of the imaging position of the objective optical system, and an eyepiece optical system with a positive refracting power. The real image mode finder optical system has an image erecting means, and the focal length of the objective optical system can be made shorter than that of the eyepiece optical system. In this case, the real image mode finder optical system satisfies the following condition:0.52&#x3c;&#x3c;1where mh is the maximum width of the field frame and fe is the focal length of the eyepiece optical system.

Real image mode finder optical system

A real image type view finder comprising an objective optical system which has positive refractive power and forms an intermediate image, an image erecting optical system which erects the intermediate image and an eyepiece optical system which leads the intermediate image to an observer's eye, in which the objective optical system comprises a first positive lens unit, a second negative lens unit, a third negative lens unit and a fourth positive lens unit, moves the second lens unit and the third lens unit for a magnification change, has a vari-focal ratio on the order of 4, and has favorable optical performance over an entire zooming region.

Real image type view finder

A camera of this invention incorporates a finder unit capable of changing its magnification corresponding to any one of plural zoom lens barrels (first, second lens barrels) each having different zoom range. When installing the finder unit, first, a positioning pin is inserted into a positioning hole in a rotary frame so as to hold the lens barrel in standard zoom condition. Then, a finder positioning pin is inserted into a cam gear positioning hole and main body positioning hole in finder cam shaft so as to hold a finder lens at a variable magnification position corresponding to the standard zoom condition. With that condition, a zoom driving gear arrangement is meshed with a driving gear portion and cam gear in a rotary frame so that the lens barrel and finder are assembled with each other. This camera realizes reduction of product development term and production cost.

Camera and method of manufacturing camera

An image pickup lens system which comprises a first positive lens unit and a second negative lens unit in order from the object side, and is configured to change a magnification by varying an airspace reserved between the first lens unit and the second lens unit, wherein the first lens unit comprises, in order from the object side, a plastic lens element having a weak refractive power, a negative glass lens element and a positive glass lens element, and wherein the second lens unit comprises, in order form the object side, a plastic lens element having a weak refractive power and a plastic lens element having a negative refractive power; the lens system is compact and light in weight, has performance which is varied little by changes in temperature and humidity, and can be manufactured at a low cost. Furthermore, a compact camera which is equipped with the image pickup lens system.

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Kokubunji, Japan

Akiyoshi Tochigi