Sony Corporation

Yusuke Nanjo

Shinichi Arita

Yuichi Nakano

Atsuo Minato

Mitsuhiro Suzaki

Koji Toyoda

Akira Kumano

Masatoshi Yamagiwa

Takashi Koyama

Masafumi Sueyoshi

Toshiaki Isogawa

Hitoshi Nakanishi

Takashi Terai

Koji Okajima

Kunioki Takahashi

Toshiaki Edamitsu

Keisuke Ikegami

Syuichi Kikuchi

Asuka Matsumoto

Disclosed herein is a zoom lens, wherein a stop moves in an optical axis direction n in a phase of zooming; a position of the stop in a telephoto end is located on an object side with respect to a position of the stop in a wide-angle end; an opening size of the stop is controlled in conjunction with the zooming so that an open F number becomes approximately constant in a range from the wide-angle end to a specific intermediate focal length; the opening size of the stop is made approximately constant in a range from the specific intermediate focal length to the telephoto end so that the open F number is changed; and the specific intermediate focal length fulfills the following conditional expression (1), wide-angle end focal length&#xd7;1.5&#x3c;specific intermediate focal length&#x3c;telephoto end focal length/1.4 . . . (1).

Zoom lens, lens barrel and image pickup apparatus

An image-capture apparatus includes a variable magnification lens, imaging means for converting an image taken by the variable magnification lens into an electrical image signal, and imaging control means. By referring to a conversion coordinate coefficient, the image control means moves a point on the image and outputs the new image signal. In the variable magnification lens, in order from the object side, a first lens group having positive refractive power, a second lens group that has negative refractive power and performs a variable magnification action by shifting on an optical axis, a third lens group having positive refractive power, a fourth lens group that has negative refractive power and a fifth lens group having positive refractive power are arrayed.

Image-capture apparatus and variable magnification lens

A tilt lens system includes a focus lens unit movable during focusing; a diaphragm sharing a primary optical axis with the focus lens unit; and a tilt lens unit, arranged on an image side of the focus lens unit and the diaphragm, having a negative refractive power and an optical axis tiltable with respect to the primary optical axis. Conditional Expressions (1) and (2) are satisfied as follows,1.3&#x3c;&#x3b2;t&#x3c;1.7&#x2003;&#x2003;(1)0&#x3c;P&#x3c;H1&#x2003;&#x2003;(2)where &#x3b2;t is a lateral magnification of the tilt lens unit in a not tilted state, P is a distance from a most object side surface of the tilt lens unit to a rotating center of the tilt lens unit in a tilted state, and His a distance from the most object side surface of the tilt lens unit to a first principal point of the tilt lens unit.

Tilt lens system and image pickup apparatus

An image capture apparatus includes: a zoom lens arranged in a housing and which includes fixed lens groups, movable lens groups and at least three prisms; and an imager device arranged in the housing. The zoom lens includes: a fixed first lens group including a negative lens group having a first optical axis, a first prism approximately perpendicularly folding an optical axis, and a positive lens group having a second optical axis folded by the first prism; movable lens groups and at least one fixed lens group arranged along the second optical axis to perform a zooming action, an image plane position correcting action and a focusing action; and a second prism arranged on an image side relative to a movable lens group that is a closest to the image side among the plurality of movable lens groups for approximately perpendicularly folding the optical axis.

Image capture apparatus and zoom lens

A zoom lens configured by arranging a first lens group, a second lens group, a third lens group, a fourth lens group, and a fifth lens group in order from the object side to the image side, and further having an aperture diaphragm on the object side of the third lens group. In the first lens group, a first lens, a second lens, and a third lens are located in order from the object side to the image side. In the second lens group, a fourth lens, a fifth lens, and a sixth lens are located in order from the object side to the image side. The third lens group is made up of a seventh lens which is a convex lens, the fourth lens group is made up of at least two or more cemented lenses, the third lens group and the fourth lens group include at least one surface formed into an aspherical surface.

Zoom lens and imaging apparatus

An image pickup apparatus having a plurality of image pickup modes and a zoom lens for use with the image pickup apparatus is configured such that, even if the dimension of an effective screen region of an image pickup element changes as a result of changeover of the image pickup mode, the change of the angle of view is moderated and good aberration correction can be achieved in any of the image pickup modes. In an image pickup apparatus (), an additional lens set (G) having a positive refractive power is positioned most adjacent the image side with respect to a zoom lens () for movement to and from a position on an optical axis of the zoom lens. Upon changeover of an image pickup mode, the additional lens set is moved to or away from the position on the optical axis to reduce or extend the focal length range of the zoom lens thereby to moderate the variation of the angle of view caused by a difference in dimension of the effective screen region of an image pickup element () when any different image pickup mode is selected. Further, the movement of the additional lens set to or from the position on the optical axis is detected to set the states of components in accordance with any image pickup mode.

Imaging device and zoom lens

A zoom lens includes, in order from an object side, a first lens group having a positive refractive power and fixed in an optical axis direction, a second lens group having a negative refractive power and moving along an optical axis to zoom, a third lens group having a positive refractive power and fixed in the optical axis direction, and a fourth lens group having a positive refractive power and moving in a non straight line along the optical axis to compensate variations of an image formation position and compensate change of the image formation position caused by changes of an object distance.

Zoom lens and image capture apparatus

A zoom lens includes in order and from the side of an object, a first lens group having a positive refractive power and fixed in position, a second lens group having a negative refractive power and movable in position for providing mainly zooming, a third lens group having a positive refractive power and fixed in position, a fourth lens group having a positive refractive power and movable in position for performing a focal position correction due to the zooming and for focusing, and a fifth lens group including a single lens fixed in position. Each of the lens groups from the third lens group to the fifth lens group has at least one aspheric surface, and conditional equations (1) and (2) below are satisfied.|4/5|&#x3c;0.12&#x2003;&#x2003;(3)0.9&#x3c;&#x3b2;5&#x3c;1.2&#x2003;&#x2003;(4)where f4 is a focal length of the fourth lens group, f5 is a focal length of the fifth lens group, and &#x3b2;5 is a transverse magnification of the fifth lens group.

There is provided a zoom lens having, in an order of an object-to-image direction, a first lens group having a positive refractive power and fixed with respect to an image plane; a second lens group having a negative refractive power; a third lens group having a positive refractive power and fixed with respect to an optical axis direction; a fourth lens group having a positive refractive power; and a fifth lens group having a positive refractive power and fixed with respect to the optical axis direction. The fifth lens group is composed of a fifth-a lens group having a negative refractive power; a fifth-b lens group having a positive refractive power; and a fifth-c lens group having a positive refractive power, arranged in the order of the object-to-image direction.

The invention concerns with an exposure control mechanism for use in an image pickup apparatus in which a diaphragm aperture formed by a plurality of diaphragm blades moving straightforward in opposite directions is covered by an ND filter, and intends to prevent deterioration of image quality caused by diffraction even in an image pickup device having a small picture size and a short pixel pitch. The image pickup apparatus comprises an exposure control mechanism for adjusting the quantity of light flux entering a shooting lens system. The exposure control mechanism comprises a diaphragm made up of diaphragm blades movable on a plane perpendicular to an optical axis in opposite directions to define a diaphragm aperture, and an ND filter made up of at least two ND filter elements having different transmittances. When the diaphragm blades are displaced from an aperture open state in a direction to restrict the quantity of transmitting light, an aperture area is restricted by the diaphragm blades from the open state to a predetermined aperture area, and thereafter the ND filter is advanced into the diaphragm aperture successively from one of the ND filter elements having the highest transmittance while the predetermined aperture area is maintained.

Exposure control method and apparatus for an image pickup apparatus

A zoom lens made up of a first lens group having positive refracting power, a second lens group having negative refracting power, a third lens group having positive refracting power, and a fourth lens group having positive refracting power, which are disposed in order from an object side, in which the first lens group and the third lens groups are stationary, and the zoom lens performs mainly variable power by shifting the second lens group in an optical axis direction, and performs correction for image position fluctuations and focusing by shifting the fourth lens group in the optical axis direction, is characterized in that the first lens group is composed of five lenses: a concave lens; a convex lens with a strong convexity facing to an image side; a cemented lens made up of a concave lens with a strong concavity facing to the image side, and a convex lens; and a convex lens with a strong convexity facing to the object side, which are disposed in order from the object side, and by satisfying each of the following conditional expressions:(1) 1.25&#x3c;1-4/1-1&#x3c;1.55;(2)1-2/1-3&#x3c;0.4;(3) 1.65&#x3c;n1-2;and(4) 0.1&#x3c;1'/1&#x3c;0.6.

Zoom lens and image pickup apparatus

When a brightness level of an object is below a predetermined level, an ND filter is removed from an iris opening to fully open the iris opening, and when the brightness level of the object is above a predetermined level, the ND filter is placed to the iris opening to fully close the iris opening. When the ND filter is moved between the fully-opened state and the fully-closed state, an exposure change amount corresponding to an amount offsetting the exposure change amount due to a state transition is generated by controlling iris blades.

Exposure control method of imaging apparatus

The present invention provides a camera system which comprises: a zoom lens; phototaking means converting an image captured by the zoom lens into an electric image signal; and image control means, in which the zoom lens is made up of a first lens group having positive refracting power, a second lens group having negative refracting power, a third lens group having positive refracting power, a fourth lens group having negative refracting power, and a fifth lens group having positive refracting power, which are disposed in this order from an object side, and is configured so that the first lens group, the third lens group, and the fifth lens group are stationary; the second lens group is shifted in an optical axis direction to mainly perform variable power; and the fourth lens group is shifted in the optical axis direction to perform correction for image position fluctuations and focusing.

Camera system and zoom lens

A zoom lens with a reduced overall length having a color separating prism therein and a telecentric property with a first lens group (GI) having a positive refractive power and having a fixed position, a second lens group (GII) of the variable magnification type having a negative refractive power and having a position movable for magnification variation, a third lens group (GIII) having a positive refractive power and having a fixed position and a fourth lens group (GIV) having a positive refractive power and having a position variable for adjustment of a focal position upon magnification variation and upon focusing are disposed in order from an object side. At least one face of the two convex lenses in the fourth lens group is formed from an aspheric face.

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Kanagawa, Japan

Yusuke Nanjo