Abstract: A zoom lens includes a lens unit Lv positioned at the most object side of a plurality of lens units having the negative refractive power, a lens unit Lp positioned at the most object side of lens units having a positive refractive power, the lens units being positioned at an image side of the lens unit Lv, and lens units Fp and Fn respectively having a positive and a negative refractive power positioned at an image side of the lens unit Lp, the lens units Fp and Fn being configured to move during focusing. During focusing from infinity to minimum object distance, the lens unit Fp and the lens unit Fn move in the same direction in a wide angle range, and the lens unit Fp moves to an object side and the lens unit Fn moves to an image side in a telephoto range.

Abstract: A zoom lens includes in order from an object side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, a fourth lens group having a positive refractive, and a last lens group having a positive refractive index, and at the time of zooming from the wide angle end to the telephoto end, the first lens group is fixed, the second lens group moves toward a side of an image plane, the third lens group is fixed, and the fourth lens group moves, and at the time of focusing, the fourth lens group moves. The zoom lens satisfies the following conditional expression (101) 0.20<log(?34T/?34W)<0.9·log ???(101).

Abstract: A zoom lens includes a frontmost lens unit, which is located closest to the object side and a plurality of lens units located closer to the image side than the frontmost lens unit. All the distances between adjacent lens units vary during zooming in the state in which the zoom lens is focused on an object at infinity. One of the plurality of lens units is a first focusing lens unit. During focusing from an object at infinity to an object at a short distance in a first shooting mode, only the first focusing lens unit moves. During focusing from an object at infinity to an object at a short distance in a second shooting mode, two lens units in the zoom lens move.

Abstract: A single focal length lens system comprising: at least a front lens unit having positive or negative power, and being fixed in focusing; a focusing lens unit having positive power, and moving along an optical axis in focusing; and a rear lens unit having negative power, and being fixed in focusing, wherein the focusing lens unit includes: a cemented lens of a negative lens and a positive lens; and a positive single lens located on the image side relative to the cemented lens and having an aspheric surface, the rear lens unit is composed of one single lens, and the condition: ?0.5<fW/fGR<?0.1 (fW, fGR: focal lengths of the entire single focal length lens system, the rear lens unit) is satisfied.

Abstract: A zoom lens includes, in order from an object side, a first unit that does not move, a negative second unit which moves during zooming, a positive third unit which moves during zooming, a positive fourth unit which moves during zooming and focus adjustment, an aperture stop that does not move in an optical axis direction, and a positive fifth unit which does not move, wherein Zinf representing a zooming ratio of the entire zoom lens when focused on infinity, ?3winf and ?3tinf representing lateral magnifications of the third unit at the wide angle end and a telephoto end, respectively, when focused on infinity, ?4tinf and ?5tinf representing lateral magnifications of the fourth unit and the fifth unit, respectively, at the telephoto end when focused on infinity, and f3 and f4 representing focal lengths of the third unit and the fourth unit, respectively, satisfy predetermined conditional expressions.

Abstract: In a zoom lens of a fixed total length, at the time of changing the magnification from the wide-angle end toward the telephoto end, the first lens group is anchored while the second lens group is moved, and the third and fourth lens groups are moved so as to be located at the object side of the telephoto end relative to the wide-angle end, such that: the interval between the second and third lens groups is decreased at the telephoto end relative to the wide-angle end; the interval between the third and fourth lens groups is increased at the telephoto end relative to the wide-angle end; and the interval between the fourth and fifth lens groups is increased at the telephoto end relative to the wide-angle end, and at the time of focusing a near object point from a remote object point, the second lens group is moved.

Abstract: A zoom lens includes: a first lens group having a negative power; and a second lens group having a refractive power, in this order from an object side. The zoom lens satisfies the following conditional formulae: 1.0<D2g/D1g<1.6, 0.08<D2t/ft<0.19, 1.15?ft/|f1|<1.8, and 1.1<ft/f2<1.9, wherein D1g is the distance from a most object side lens surface to a most image side lens surface within the first group, D2g and D2t are the distance from a most object side lens surface to a most image side lens surface within the second group and the distance between an object side partial second lens group and an image side partial second lens group when focused on infinity at a telephoto end, respectively, ft is the focal length of the entire system at the telephoto end, and f1 and f2 are the focal lengths of the first group and the second group, respectively.

Abstract: A zoom lens system has a combined focal length fw at the wide angle end and includes, in order from an object side, a first lens group with positive refractive power and combined focal length f1; a second lens group with negative refractive power; a third lens group with positive refractive power; a fourth lens group with positive refractive power; and a fifth lens group with positive refractive power and including, in order from the object side, a negative biconcave lens with focal length f51 and a positive biconvex lens with focal length f52, the negative biconcave lens and the positive biconvex lens disposed with an air space shorter than a center thickness of the negative biconcave lens in between and both surfaces of the positive biconvex lens being aspherical. The system satisfies the following conditions: 13.5<f1/fw<17.5, and 1.0<|f51/f52|<1.5.

Abstract: A zoom lens substantially consists of, in order from the object side, a positive first lens group, a negative second lens group, a positive third lens group, a positive fourth lens group, and a negative fifth lens group. When varying magnification, the distances between adjacent lens groups are changed, while all of the lens groups are moved with respect to an image formation position. If fw represents the focal length of the entire lens system at the wide angle end, f4 represents the focal length of the fourth lens group, F5 represents the focal length of the fifth lens group, and ?5T is an image formation magnification of the fifth lens group when focusing on infinity at the telephoto end, formula (J): 0.50<fw/f4<0.65, formula (K): ?0.32<fw/f5<?0.15, and (C): ?6.0<1?(?5T)2<?2.5 are simultaneously satisfied.

Abstract: Systems and methods for inspection are provided utilizing a wide angle optical system. The optical system includes a wide angle input lens group and an output lens group. The wide angle input lens group is configured to receive wide-angle radiation, e.g., having an angular spread of 60 degrees or more, from an object surface, and produce imagable radiation. The wide angle input lens group is arranged such that no intermediate focused image is formed within or after the wide angle input lens group. The output lens group is configured to receive the imagable radiation from the wide angle input lens group and focus the imagable radiation onto an image plane to image at least part of the object surface. A detector receives the image of the at least part of the object surface and, based on the received image, detects, for example, contamination on the object surface.

Abstract: A zoom lens substantially consists of, in order from the object side, a positive first lens group, a negative second lens group, a positive third lens group, a positive fourth lens group, and a negative fifth lens group. When varying, the distances between adjacent lens groups are changed, while all of the lens groups are moved with respect to an image formation position. Further, when focusing, only the fifth lens group is shifted to the image side. If fw represents the focal length of the entire lens system at the wide angle end, f2 represents the focal length of the second lens group, and ?5T represents an image formation magnification of the fifth lens group when focusing on infinity at the telephoto end, formula (F): ?1.5<fw/f2<0.5 and formula (C?): ?5.00?1?(?5T)2<?2.5 are satisfied.

Abstract: A variable magnification optical system includes a positive first lens group, a negative second lens group, a stop, a positive third lens group and a positive fourth lens group, which are in this order from an object side. The first lens group, the stop and the third lens group are fixed, but the second lens group and the fourth lens group move in an optical axis direction during magnification change. The fourth lens group has a focusing function. The third lens group includes at least an aspherical surface, and consists of, in the following order from the object side, a positive lens and a cemented lens of a positive lens and a double-concave lens cemented together. The variable magnification optical system satisfies a predetermined formula.

Abstract: A macro lens system and a pickup device that includes the macro lens system include, in order from an object side to an image side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, a fourth lens group having a positive refractive power, and a fifth lens group having a negative refractive power, wherein, during focusing, the first lens group, the third lens group, and the fifth lens group are fixed, and the second lens group and the fourth lens group are moved.

Abstract: A single focal length lens system comprising a front lens unit, an aperture diaphragm, and a rear lens unit, wherein the front lens unit is composed of three or less lenses including a negative lens located closest to the object side and a positive lens located on the image side relative to the negative lens, and does not move along an axis in focusing, the rear lens unit includes a focusing lens unit moving along the axis and a fixed lens unit not moving along the axis in focusing, and the conditions: 0.4<fW/fGF<1.5, 0.9<fW/T1<4.5, and ?0.3<fW/fG1<0.3 (fW, fGF, fG1: focal lengths of the entire single focal length lens system, the focusing lens unit, the front lens unit, T1: an axial distance from an object side lens surface of the negative lens to the aperture diaphragm) are satisfied.

Abstract: A zoom lens system, in order from an object side to an image side, comprising a positive first lens unit, a negative second lens unit, a positive third lens unit, and a positive fourth lens unit, wherein the first lens unit is composed of a cemented lens element of one object side negative lens element and one image side positive lens element, the fourth lens unit is composed of one lens element, in zooming, the first to fourth lens units are individually moved along an optical axis so that air spaces between the respective lens units vary for magnification change, and the conditions: vdL12<43.50 and fT/fW?6.0 (vdL12: an Abbe number of the positive lens element in the first lens unit, fT and fW: focal lengths of the entire system at a telephoto limit and a wide-angle limit) are satisfied; an imaging device; and a camera.

Abstract: A zoom lens includes, in order from an object side to an image side, a first lens unit of a negative refractive power, a second lens unit of a positive refractive power, and a third lens unit of a positive refractive power, an interval between the first lens unit and the second lens unit and an interval between the second lens unit and the third lens unit being configured to change in zooming from a wide angle end to a telephoto end. The first lens unit includes, in order from the object side to the image side, a negative lens and a positive lens. The predetermined conditions are satisfied.

Abstract: A zoom lens system, in order from an object side to an image side, comprising a first lens unit having negative optical power, a second lens unit having positive optical power, a third lens unit having negative optical power, and a fourth lens unit having positive optical power, wherein the first lens unit is composed of at least three lens elements, has at least one lens element having positive optical power, and moves along an optical axis in zooming, and the conditions: np>1.88 and 1.5<fp/fW<4.0 (np and fp: a refractive index to the d-line and a focal length of a lens element having the highest refractive index among the lens elements having positive optical power in the first lens unit, fW: a focal length of the entire system at a wide-angle limit) are satisfied; an interchangeable lens apparatus; and a camera system are provided.

Abstract: Provided is a zoom lens, including, in order from an object side to an image side: a first lens unit having a positive refractive power which does not move; a second lens unit having a negative refractive power which moves during zooming and focusing; a third lens unit having the negative refractive power which moves during zooming; a fourth lens unit having one of the negative refractive power and the positive refractive power; and a fifth lens unit having the positive refractive power, in which a lateral magnification (?2w) of the second lens unit at a wide angle end when an object distance is infinity, and a ratio of a focal length (f2) of the second lens unit and a focal length (f3) of the third lens unit are appropriately set.

Abstract: 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<f1/f 14 (1), and 0.8<f23/f2<3 (2).

Abstract: During zooming from the wide angle end to the telephoto end, a first lens unit having a positive refractive power is fixed, a second lens unit having a negative refractive power moves toward the image side, a third lens unit having a positive refractive power moves toward the object side, a fourth lens having a negative refractive power unit moves, and a fifth lens unit having a positive refractive power is fixed. The first lens unit includes a reflecting member that bends the optical path by 90 degrees. The entirety of or at least a part of the fifth lens unit is shifted in directions transverse to the optical axis to stabilize a picked-up image when the optical system vibrates. The zoom lens satisfies the predetermined expressions.

Abstract: A zoom lens includes first to fifth lens groups having positive, negative, negative, positive, and positive refractive powers, respectively, arranged along an optical axis in order from an object side, and an aperture stop disposed between the third and fourth lens groups. When zooming from wide angle end to telephoto end, the zoom lens is moved so that an interval between the first and second lens groups increases, an interval between the second and third lens groups varies, an interval between the third and fourth lens groups decreases, and the third lens group focuses. The second lens group is arranged to have a focal length to satisfy the following condition: 0.95<|f2/?(fw*ft)|<4.0 where f2 is a focal length of the second lens group, fw and ft are focal lengths of the entire zoom lens at wide angle end and at telephoto end, respectively.

Abstract: A zoom lens includes: a first lens group having negative refractive power; a diaphragm; 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, arranged in order from an object side. The first lens group is configured by at least one negative lens and one positive lens. The third lens group is configured by one negative lens. Then power is changed from a wide angle end state to a telephoto end state, the first, second, and third lens groups are moved in the direction of an optical axis, and the fourth lens group is fixed. When focusing, the third lens group is moved in the direction of the optical axis so as to satisfy the following Conditional Equations, ?2.8<f3/fw<?0.5??(1) 2.0<f4/fw<15.0??(2).

Abstract: A zoom lens consists of a positive first lens group, a negative second lens group, a positive third lens group, and a positive fourth lens group, which are arranged in this order from an object side. When magnification is changed from wide angle end to telephoto end, the first lens group and the third lens group are fixed, and the second lens group moves toward an image side, and the fourth lens group moves. The first lens group consists of a cemented lens of a negative lens and a positive lens, and two positive lenses, which are in this order from the object side. The third lens group consists of a negative partial lens group including a cemented lens, and a positive partial lens group, which are in this order from the object side.

Abstract: An internal focus lens comprising sequentially from an object side a first lens group having a positive refractive power; a second lens group having a negative refractive power; and a third lens group having a positive refractive power. The second lens group is configured by a simple lens element and is moved along an optical axis to perform focusing. The internal focus lens satisfies condition expressions (1) 0.48<|f3|/f<0.73 and (2) 1.05<Fno×f1/f<1.42, where f3 is the focal length of the third lens group, f is the focal length of the entire optical system, f1 is the focal length of the first lens group, and Fno is the F number of the entire optical system.

Abstract: A zoom lens and a photographing apparatus including the same. The zoom lens includes a first lens group having a positive refractive power, a second lens group having a negative refractive power, and an additional lens grouping having a positive refractive power, which are sequentially arranged from an object side, wherein the additional lens grouping comprises a third lens group having a positive refractive power.

Abstract: A zoom lens includes, in order from an object side to an image side, a first lens unit having a negative refractive power, a second lens unit having a positive refractive power, a focus lens unit having a negative refractive power, configured to move in focusing, and a final lens unit having a positive refractive power, disposed closest to the image side. The focus lens unit and the final lens unit are disposed so as to be adjacent to each other, each lens unit moves so that a distance between adjacent lens units changes in zooming, and a focal length of the final lens unit fimg, a focal length of the focus lens unit ff, and a focal length of an entire system at a wide-angle end fw are appropriately set.

Abstract: A zoom lens includes, in order from an object side to an image side, first to fourth lens units having negative, positive, negative, and positive refractive power, respectively. Each lens unit moves during zooming so that a distance between the first lens unit and the second lens unit at the telephoto end is shorter than at the wide-angle end and a distance between the second lens unit and the third lens unit and a distance between the third lens unit and the fourth lens unit at the telephoto end are larger than those at the wide-angle end. A focal length of the third and fourth lens units, a focal length of the entire zoom lens at the wide-angle end, a focal length of the entire zoom lens at the telephoto end, and a sum of axial thicknesses of the first to fourth lens units are appropriately set.

Abstract: A zoom lens includes first to fifth lens groups having positive, negative, negative, positive, and positive refractive power, respectively. The third lens group includes a single negative meniscus lens with a concave surface on an object side, to move along the optical axis for focusing. When zooming from a wide angle end to a telephoto end, an interval between the first and second lens groups increases, an interval between the second and third lens groups increases, an interval between the third and fourth lens groups decreases, and an interval between the fourth and fifth lens groups decreases. The fourth and fifth lens groups are set to have a combined lateral magnification ?45T to satisfy the following condition, when an object distance is infinite at a telephoto end: ?0.041<?45T/Ft<?0.025 where Ft is a focal length of the entire zoom lens at the telephoto end.

Abstract: A zoom lens consists of, in order from an object side to an image side, a first lens unit having negative refractive power, a second lens unit having positive refractive power, and a third lens unit having negative refractive power. The first lens unit and the second lens unit move during zooming to make a distance between the first lens unit and the second lens unit larger at a telephoto end than at a wide-angle end. The third lens unit consists of, in order from the object side to the image side, a first lens subunit having positive refractive power and a second lens subunit having negative refractive power, and the second lens subunit moves toward the image side during focusing from an infinite-distance object to a near-distance object.

Abstract: A zoom lens includes, in order from an object side to an image side, a lens unit Ln having the highest negative refractive power of all the following lens units, a lens unit Lm2 having positive refractive power, a lens unit Lm having negative refractive power, and a rear lens group Lp including one or more lens units and having overall positive refractive power. During zooming, a distance between every adjacent lens units varies. During focusing from an infinite distance to a minimum object distance, the lens unit Ln and the lens unit Lm move toward the object side. The focal length FLm of the lens unit Lm and the focal length FLm2 of the lens unit Lm2 are appropriately set.

Abstract: Compact and lightweight zoom lens systems having less aberration fluctuation in association with focusing, lens barrels, interchangeable lens apparatuses, and camera systems are provided. The zoom lens system comprises: a first lens unit having positive optical power; a first focusing lens unit which is located on an image side relative to the first lens unit, has negative optical power, and moves along an optical axis in zooming and focusing; and a second focusing lens unit which is located on the image side relative to the first focusing lens unit, has positive optical power, and moves along the optical axis in the zooming and the focusing, and satisfies the condition: |d2T/d1T|<1.0 (d1T: an amount of movement of the first focusing lens unit in focusing at a telephoto limit, d2T: an amount of movement of the second focusing lens unit in focusing at a telephoto limit).

Abstract: The zoom lens includes at least five lens groups including first, second, third, fourth and fifth lens groups respectively having positive, negative, negative, positive and positive refractive powers. At least four movable lens groups are moved during zooming. At least two movable lens groups placed further on an image side than an aperture. C1 and C2 lens groups are moved so as to draw mutually different loci and such that a distance therebetween becomes maximum at a middle zoom position. The C1 and C2 lens groups are located further on a same side at the telephoto end than at a wide-angle end. At least one of D1 and D2 lens groups is moved during the zooming so as to be located further on an object side at a telephoto end than at the wide-angle end. A distance therebetween at the telephoto end becomes larger than that at wide-angle end.

Abstract: A zoom lens system has a front lens group and a rear lens group along the optical axis and in order from the object side. The rear lens group has a first lens unit having a positive refracting power, a second lens unit having a negative refracting power, and a third lens unit having a positive refracting power. Upon zooming from a wide-angle end state to a telephoto end state, a space between the front lens group and the first lens unit varies, a space between the first lens unit and the second lens unit increases, and a space between the second lens unit and the third lens unit decreases. At least a part of the second lens unit is movable so as to have a component in a direction perpendicular to the optical axis.

Abstract: Disclosed is a zoom lens that forms an optical image of an object on a light receiving surface of an imaging element converting the optical image to an electrical signal, having the diagonal length of 2Y max, is constituted by a positive first group, a negative second group, a negative third group, an aperture, and a rear group having positive power as a whole, in order from an object side, and satisfies a conditional expression 1.5<frw/Ymax<2.1 (frw denotes the combined focal length of the rear group on a wide end, and Ymax denotes the maximum image height).

Abstract: A zoom lens comprising sequentially from an object side a first lens group having a positive refractive power; a second lens group having a negative refractive power; a third lens group having a positive refractive power; a fourth lens group having a negative refractive power; and a fifth lens group having a positive refractive power and formed by a cemented lens alone that includes a negative lens and a positive lens. The zoom lens zooms from a wide angle edge to a telephoto edge by moving the second lens group along an optical axis, from the object side toward the image plane side. The zoom lens performs focusing and corrects image plane variation accompanying zoom by moving the fourth lens group along the optical axis, and corrects image blur caused by minute vibrations by moving the entire fifth lens group in a direction orthogonal to the optical axis.

Abstract: A zoom lens system, in order from an object side to an image side, comprising: a first lens unit having positive optical power; a second lens unit having negative optical power; a third lens unit having positive optical power; a fourth lens unit having negative optical power, and a subsequent lens unit, wherein the first lens unit comprises a negative lens element having negative optical power, and a positive lens element having positive optical power, and wherein the conditions: 1.47<nd2<1.57 and 60<?d2<75 (nd2: a refractive index to a d-line of the positive lens element, ?d2: an Abbe number to a d-line of the positive lens element) are satisfied.

Abstract: A zoom lens system comprising a negative first lens unit, a positive second lens unit, a negative third lens unit, and a positive fourth lens unit, wherein the first lens unit and the third lens unit move along an optical axis, and the fourth lens unit is fixed with respect to an image surface in zooming, the third lens unit moves along the optical axis in focusing, and the conditions: 0.0<|M3/fW|<0.5 and 0.2<|f3/f4|<1.0 (M3: an amount of movement of the third lens unit in zooming, f3: a composite focal length of the third lens unit, f4: a composite focal length of the fourth lens unit, fW: a focal length of the entire system at a wide-angle limit) are satisfied.

Abstract: A zoom lens system comprising a plurality of movable lens units which individually move along an optical axis at the time of zooming from a wide-angle limit to a telephoto limit during image taking, wherein at least two of the movable lens units are focusing lens units which move along the optical axis at the time of focusing from an infinity in-focus condition to a close-object in-focus condition in at least one zooming position, and among the focusing lens units, a lens unit having the absolute value, which is not the greatest absolute value, of a wobbling value at a wide-angle limit is a wobbling lens unit which senses a moving direction of the focusing lens units at the time of focusing by wobbling itself in a direction along the optical axis; an interchangeable lens apparatus; and a camera system are provided.

Abstract: A zoom lens system includes, in order from an object side: a first lens group having positive refractive power; a second lens group having negative refractive power; a third lens group having positive refractive power; a fourth lens group having negative refractive power; and a fifth lens group having positive refractive power. Upon zooming from a wide-angle end state to a telephoto end state, a position of the first lens group is fixed. At least a portion of any one of the lens groups is moved in a direction including a component perpendicular to an optical axis, and a given conditional expression is satisfied, thereby providing a zoom lens system capable of excellently suppressing variation in aberrations upon zooming and upon correcting an image blur, an optical apparatus including the zoom lens system, and a method for manufacturing the zoom lens system.

Abstract: An internal focusing lens includes sequentially from an object side, a first lens group having a positive refractive power; a second lens group having a negative refractive power; and a third lens group having a positive refractive power. During focusing, the second lens group is moved along the optical axis and, the first lens group and the third lens group are fixed. The internal focusing lens satisfies a conditional expression (1) 0.31<f1/f<0.58, where f1 is the focal length of the first lens group and f is the focal length of the entire optical system, at infinity focus.

Abstract: The zoom lens of the invention comprises, in order from an object side thereof, 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 positive refracting power, a fifth lens group having negative refracting power, and a sixth lens group having positive refracting power. The first lens group includes a reflective optical element, and the lens component in, and on the most image side of, the fourth lens group has negative refracting power.

Abstract: A zoom lens system ZL comprising, in order from an object side: a first lens group G1 having positive refractive power; a second lens group G2 having negative refractive power; a third lens group G3 having positive refractive power; a fourth lens group G4 having negative refractive power; and a fifth lens group G5 having positive refractive power; upon zooming the first lens group G1 being fixed with respect to an image plane in the direction of the optical axis, upon focusing at least a portion of the third lens group G3 being moved along the optical axis, and the zoom lens system satisfying predetermined conditions, whereby there are provided a zoom lens system that is capable of realizing excellent optical performance and has a high zoom ration and also well-corrected aberrations having excellent optical performance, an optical apparatus equipped with the zoom lens system, and a method for manufacturing the zoom lens system.

Abstract: A zoom lens includes, in order from an object side to an image side, a first lens unit having positive refractive power, a second lens unit having negative refractive power, a third lens unit having positive or negative refractive power, and a rear lens group including one or more lens units, an aperture stop is provided on the image side of the second lens unit. A sum of relative anomalous partial dispersion ??gF of materials of negative lenses included in the second lens unit, a sum of power of a negative lens formed of a material having relative anomalous partial dispersion that is equal to or more than an average value of relative anomalous partial dispersion of the materials of the negative lenses included in the second lens unit, and a refractive power of the second lens unit are appropriately set.

Abstract: A zoom lens includes a first lens unit of a positive refractive power, a second lens unit of a negative refractive power, a third lens unit of a positive refractive power, and a fourth lens unit of a positive refractive power, wherein the first lens unit does not move for zooming, at least the second and fourth lens units are moved during zooming, the first lens unit includes at least one positive lens, and an Abbe number and a relative partial dispersion of a material of the positive lens, an average refractive index of materials of negative lenses included in the second lens unit, a movement amount of the second lens unit for zooming from a wide-angle end to a telephoto end, a focal length of the second lens unit, and a focal length of the entire zoom lens at the telephoto end are appropriately set.

Abstract: A zoom lens includes a first lens group, a second lens group, an aperture, a third lens group, a fourth lens group, a fifth lens group, and an image surface in order along an optical axis from an object side to an image side. The first lens group has positive refractive power, and includes three lenses. The second lens group has negative refractive power, and includes fourth lenses. The third lens group has positive refractive power, and includes two lenses. The fourth lens group has positive refractive power, and includes five lenses. The fifth lens group has positive refractive power, and includes two lenses. Therefore, the zoom lens has a small size and high zoom ratio.

Abstract: A zoom lens ZL including an optical element P for deflecting an optical path, including, in order from an object: a first lens group G1 having positive refractive power; a second lens group G2 having negative refractive power; a third lens group G3 having positive refractive power; a fourth lens group G4 having positive refractive power; a fifth lens group G5 having negative refractive power; and a sixth lens group G6, wherein a conditional expression 0.10<fw/PL<0.45 is satisfied, where fw denotes a focal length of the zoom lens ZL in a wide-angle end state, and PL denotes an optical path length of the optical element P for deflecting the optical path.

Abstract: A zoom lens system includes a negative first lens group, a positive second lens group, and a positive third lens group, in that order from the object side, wherein upon zooming from the short focal length extremity to the long focal length extremity, the distance between the first lens group and the second lens group decreases, and the distance between the second lens group and the third lens group increases. The second lens group includes a positive first sub-lens group and a negative second sub-lens group, in that order from the object side. The second sub-lens group is a negative single lens element serving as an image-stabilizer lens group which moves in directions orthogonal to the optical axis to change the imaging position to correct image shake.

Abstract: A zoom optical system ZL to be mounted on an optical apparatus such as a single lens reflex camera 1, comprising, in order from an object side, a first lens group G1 having positive refractive power, a second lens group G2 having negative refractive power, a third lens group G3 having positive refractive power, a fourth lens group G4 having negative refractive power, a fifth lens group G5 having positive refractive power, and a sixth lens group G6 having negative refractive power. The zoom optical system is configured such that at least a portion of any one lens group among these lens group G1 to G6 may be moved such that a component in a direction perpendicular to the optical axis may be included. Thus, there are provided a zoom optical system that can suppress well variation in aberrations upon zooming, an optical apparatus equipped therewith and a method for manufacturing the zoom optical system.

Abstract: A zoom lens system includes a positive first lens group, a negative second lens group, and a positive rearward-remaining lens group. Upon zooming from the short to long focal length extremities, the distance between the first and second lens groups increases, the distance between the second and rearward-remaining lens groups decreases, and at least the first lens group and at least part of the rearward-remaining lens group moves. The second lens group includes a negative first sub-lens group which does not move during a focusing operation, and a negative second sub-lens group which moves in the optical axis direction during a focusing operation. The positive rearward-remaining lens group includes at least two lens groups, the distance therebetween mutually changing during zooming from the short focal length extremity to the long focal length extremity.

Abstract: A zoom lens includes a positive first lens group, which is fixed during changing magnification and during focusing, a negative second lens group, which is moved during changing magnification, a positive third lens group, which is fixed during changing magnification and during focusing, a positive fourth lens group, which is moved during changing magnification and during focusing, and a negative fifth lens group, which is moved during changing magnification, which are in this order from an object side. A lens group constituting the first lens group consists of a negative front group and a positive rear group in this order from the object side. The second lens group consists of four lenses of a negative lens, a positive lens, a negative lens, and a positive lens or a negative lens arranged in this order from the object side.