Abstract: A zoom lens exhibits a reduction in size, increased magnification, a reduction in variation of angle of view during zooming, and an increased focusing speed, said zoom lens being suitable for an imaging apparatus using a solid-state imaging device such as an interchangeable lens, a digital still camera, a digital video camera, or the like. The zoom lens has, in the lens system, at least: a first negative lens group having negative refractive power; a second negative lens group disposed further towards the image side than the first negative lens group, and which has negative refractive power; and a lens group (A) disposed so as to be adjacent to the image side of the second negative lens group. In the zoom lens, focusing from an infinite distance to a near object is performed by moving only the second negative lens group towards the image side, and prescribed conditions are satisfied.

Abstract: A zoom lens includes, in order from an object side to an image side, first, second, third, and fourth lens groups with positive, negative, negative, and positive refractive powers, respectively. When varying magnification from a short focal length end to a long focal length end, the second lens group is moved to the image side, the third lens group is moved, and the first and fourth lens groups are fixed. The fourth lens group is constituted of a lens group on the object side and a lens group on the image side with a largest distance in the fourth lens group between them. Each of a refractive index, Abbe number, a partial dispersion ratio, and the like of each of at least one positive lens of the lens group on the object side and two positive lenses of the first lens group is regulated to be in a predetermined 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 negative refractive power, and a fourth lens group having a positive refractive power. During change of magnification from a short focal end to a long focal end, the first lens group is fixed, the second lens group is moved to an image side, the third lens group is moved, and the fourth lens group is fixed. The first lens group and the fourth lens group include diffraction surfaces and satisfy the Condition Expressions 50<f1doe/f1<200 (1) and 100<f4doe/f4<300 (2).

Abstract: A zoom lens system comprising: a positive first lens unit; a negative second lens unit; a positive third lens unit; a fourth lens unit; and at least one subsequent lens unit, wherein the subsequent lens unit(s) includes a negative lens unit, the first and third lens units are respectively composed of two or less lens elements and four or more lens elements, the first and second lens units move along an optical axis in zooming, and the conditions: 0.0<LGmax/LG2<1.5, 0.2<|f2/fW|, and 0.1<|fe/f2| (LGmax: a maximum value of an axial thickness of the subsequent lens unit(s), LG2: an axial thickness of the second lens unit, fW, f2, and fe: focal lengths of the entire system at a wide-angle limit, the second lens unit, and a negative lens unit located closest to the image side) are satisfied.

Abstract: A zoom lens includes a first positive lens unit, a first negative lens unit, a stop, and a second positive lens unit, and at the time of zooming, the first positive lens unit is stationary, the first negative lens unit and the second positive lens unit move, and at the time of focusing, the first positive lens unit is stationary, and the first positive lens unit includes a reflecting member and a first positive lens unit object-side system, and the first positive lens unit-object side system is positioned on the object side of the reflecting member, and has a negative refractive power, and the following conditional expressions are satisfied. 3.7<ft/fw 1.55<|D1N/D2P|<2.5 1.75<|f2P/D2P|<2.

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; and at least one subsequent lens unit, wherein the subsequent lens unit(s) includes a lens unit having negative optical power, the first lens unit is composed of two or less lens elements, the third lens unit is composed of four or more lens elements, the first lens unit and the second lens unit move along an optical axis in zooming, and the condition: 0<|fW/fe<2 (fe: a focal length of a lens unit having negative optical power and located closest to the image side in the entire system, fW: a focal length of the entire system at a wide-angle limit) is satisfied.

Abstract: A compact optical imaging lens can include a front lens group, a rear lens group, and a reflective element to redirect light passing through the system. The reflective element can be placed in front of the front lens group or between the front and rear lens group. In some cases, multiple reflective elements can be used. The use of reflective elements can reduce the depth of the imaging system, allowing for more compact designs.

Abstract: The zoom lens substantially consists of a positive first lens group fixed while changing magnification, a negative second lens group which moves from the object side to the image side while changing magnification, a positive third lens group which moves while changing magnification, and a positive fourth lens group which moves from the image side to the object side while changing magnification, and a positive fifth lens group fixed while changing magnification in this order from the object side. A floating system in which the third lens group and the fourth lens group move relative to each other while changing magnification is adopted. The image formation magnification rates of the combined lens group formed by the third lens group and the fourth lens group together and the second lens group simultaneously pass ?1× point while changing magnification from the wide angle end to the telephoto end.

Abstract: A zoom lens system, in order from an object side to an image side, includes 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. The first lens unit includes a negative lens element and a positive lens element. In the zoom lens system, the conditions: 1.47<nd2<1.57 and 60<vd2<75 (nd2: a refractive index to a d-line of the positive lens element, vd2: an Abbe number to a d-line of the positive lens element) are satisfied.

Abstract: The zoom lens includes, in order from an object side to an 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 positive refractive power, and a fifth lens unit having a negative refractive power. During zooming, the second lens unit is not moved and the first, third and fifth lens units are moved. A distance between the first and second lens units at a telephoto end is larger than that at a wide-angle end, a distance between the second and third lens units at the telephoto end is smaller than that at the wide-angle end. A condition of 0.7<f3/f4<1.5 is satisfied where f3 represents a focal length of the third lens unit, and f4 represents a focal length of the fourth lens unit.

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: The zoom lens substantially consists of a positive first lens group which is fixed while changing magnification, a negative second lens group which moves while changing magnification, a positive third lens group which moves while changing magnification, and a positive fourth lens group which is fixed while changing magnification in this order from the object side. The image formation magnification rates of the second lens group and the third lens group simultaneously pass a ?1× point while changing magnification from the wide angle to the telephoto. The second lens group substantially consists of a negative second-a lens group and a positive second-b lens group which independently move while changing magnification in this order from the object side, and the third lens group substantially consists of a positive third-a lens group and a positive third-b lens group which independently move while changing magnification in this order from the object side.

Abstract: A variable magnification optical system substantially consists of a first lens-group having positive refractive-power, and which is fixed during magnification change, a second lens-group having negative refractive-power, a third lens-group having negative refractive-power, a fourth lens-group having negative refractive-power, an aperture stop, which is fixed during magnification change, and a fifth lens-group having positive refractive-power, and which is fixed during magnification change, in this order from an object-side along an optical-axis.

Abstract: A zoom lens includes, in order from an object 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 negative refractive power, and a fourth lens unit having a positive refractive power. During change of magnification from the short focal end to the long focal end, the first lens unit is stationary, the second lens unit is moved to an image side, the third lens unit is moved, and the fourth lens unit is stationary. A positive lens, included in the fourth lens unit or the first lens unit, satisfies the condition formulas: 1.40<nd<1.65; 65.0<?d<100.0; and 0.015<Pg,F?(?0.001802×?d+0.6483)<0.060, and the first lens unit includes a diffraction plane and satisfies the condition formula: 50<fdoe/f1<200.

Abstract: A zooming optical system has, from the object side, a positive first group, a negative second group, a positive third group, a positive fourth group, and a negative fifth group. During zooming, at least the third to fifth groups move relative to the image plane, and focusing is achieved by moving the fourth group along the optical axis. The conditional formula ?1.0<M5/f5<?0.1 is fulfilled, where M5 is the distance along the optical axis from the position of the fifth group at the wide-angle end to the position of the fifth group at the telephoto end and f5 is the focal length of the fifth group.

Abstract: The 1st positive lens unit is located closer to the object side at the telephoto end than at the wide angle end. The distance between the 1st negative lens unit and the 1st positive lens unit is larger at the telephoto end than at the wide angle end. The distance between the image side lens unit group and the 1st negative lens unit varies during zooming from the wide angle end to the telephoto end. The image side lens unit group comprises a 2nd positive lens unit and a 3rd positive lens unit. The distance between the 2nd positive lens unit and the 1st negative lens unit is smaller at the telephoto end than at the wide angle end. The distance between the 3rd positive lens unit and the 2nd positive lens unit varies during zooming from the wide angle end to the telephoto end.

Abstract: A zoom lens includes in order from an object side to an 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, and a fourth lens unit having a negative refractive power, and includes an aperture stop which is disposed between the second lens unit and the fourth lens unit, and the first lens unit includes a negative lens and a plurality of positive lenses, and 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 widens, a distance between the second lens unit and the third lens unit narrows, and a distance between the third lens unit and the fourth lens unit changes, and the zoom lens satisfies predetermined conditional expressions.

Abstract: An optical system for imaging an object on an image acquisition unit. The optical system, from the object, comprises a first lens unit, a second lens unit, a third lens unit and a fourth lens unit in the direction of the image acquisition unit. The first lens unit comprises at least one lens group with negative refractive power. The second lens unit comprises at least one lens group with positive refractive power and the third lens unit comprises at least one lens group with negative refractive power. The second lens unit and the third lens unit overall comprise at least three lens groups. From the first lens unit in the direction of an image acquisition unit, the first lens group, the second lens group and then the third lens group are arranged. The three lens groups have a movable design for adjusting the focal length of the optical system.

Abstract: A zoom lens includes, in order from an object side to an image side, a first, a second, a third, a fourth and a fifth lens units respectively having positive, negative, positive, negative, and positive refractive powers. The first lens unit includes negative, positive, and positive lenses in order from the object side to the image side. The second lens unit includes negative, negative, and positive lenses in order from the object side to the image side. Each lens unit moves during zooming. The predetermined conditional expressions are satisfied.

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: The zoom lens has an aperture stop arranged between the second lens unit and the fourth lens unit. During zooming from the wide angle end to the telephoto end, the distances between the lens units vary in such a way that the distance between the first lens unit and the second lens unit is larger at the telephoto end than at the wide angle end, the distance between the second lens unit and the third lens unit is smaller at the telephoto end than at the wide angle end, and the distance between the fourth lens unit and the fifth lens unit is larger at the telephoto end than at the wide angle end. The zoom lens satisfies the following conditional expression (1): 3.5?LTLw/IHt?8.9??(1).

Abstract: A zoom lens includes N lens units, in which a lens unit having a positive refractive power is disposed closest to an object side. Each lens unit is moved to effect zooming. An (N?1)th lens unit and an N-th lens unit, counted from the object side, have positive refractive powers. The (N?1)th lens unit includes a first lens subunit having a positive refractive power and a second lens subunit having a negative refractive power in order from the object side to an image side. The second lens subunit is moved to have a component in a direction perpendicular to an optical axis to move an image position. A focal length fN of the N-th lens unit, a back focus bkt at the telephoto end, and an amount of movement mN of the N-th lens unit during zooming from a wide-angle end to a telephoto end are appropriately set.

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 refractive power, and a rear lens group including one or more lens units. An interval between adjacent lens units is changed in zooming, the first lens unit is moved closer to the object side at a telephoto end than at a wide-angle end. The first lens unit includes at least four lenses. An Abbe number and a material of a positive lens included in the first lens unit satisfy predetermined values. And, a focal length f1 of the first lens unit, and an amount of movement M1 of the first lens unit at zooming from the wide-angle end to the telephoto end are appropriately set.

Abstract: Provided is a zoom lens, including, in order from object side to image side: first and second lens units having positive and negative powers, respectively; and three or more lens units. An interval between adjacent ones of the lens units is changed during zooming. An N-th lens unit, where 5?N holds, counted from object side has negative refractive power, and moves to image side during focusing from infinite object to a close distance object. The N-th lens unit includes, in order from object side to image side, negative, positive, negative, and positive lenses. A focal length (fN) of N-th lens unit, a focal length (fT) of an entire system at telephoto end, a distance (o1N) from a surface vertex of N-th lens unit on object side to a front principal point position of N-th lens unit, and a length (dN) on optical axis of N-th lens unit are appropriately set.

Abstract: A zoom lens includes, 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 negative refractive power; and a fifth lens group having a negative refractive power. During zooming from a wide-angle end state to a telephoto end state, air spacing between the first and second lens groups increases, air spacing between the second and third lens groups decreases, spacing between the third and fourth lens groups changes, and spacing between the fourth and fifth lens groups changes. Thus, all the lens groups are moved in an optical axis direction. The zoom lens satisfies the following Conditional Expression (1). 1.0<?5w?4.0??(1) Here, ?5w is a lateral magnification of the fifth lens group at a wide-angle end.

Abstract: A zoom lens including: 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 in this order from an object side to an image side. During zooming, the lens units move such that an interval between adjacent lens units varies. The third lens unit includes at least two positive lenses. A partial dispersion ratio (?gF3P) of a material and the Abbe number (?d3P) of a positive lens included in the third lens unit satisfy the following conditional expressions, ?gF3P?(?1.665×10?7·?d3P3+5.213×10?5·?d3P2?5.656×10?3·?d3P+0.737)>0 50.0<?d3P<100.0.

Abstract: A zoom lens includes 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, in this order from an object side, and a stop located between a most image-side surface of the second lens-group and a most image-side surface of the third lens-group. Distances between the lens-groups change when magnification is changed from a wide-angle end to a telephoto end. The second lens-group consists of a negative lens, a biconcave lens and a positive lens in this order from the object side. The third lens-group consists of a positive lens, a cemented lens of a positive lens and a negative lens, a negative meniscus lens with its concave surface facing the object side, and a biconvex lens in this order from the object side. A predetermined conditional formula is satisfied.

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 for zooming; a second lens unit having a negative refractive power which moves during zooming; and an N-th lens unit having a positive refractive power which does not move for zooming and is arranged closest to the image side. In the zoom lens, the N-th lens unit includes in order from an object side: a first sub-lens unit; and a second sub-lens unit which is movable, and a lateral magnification at a wide angle end of the N-th lens unit and a lateral magnification at a wide angle end of the second sub-lens unit of the N-th lens unit when an axial ray enters from infinity in a state in which focus is at the infinity are appropriately set.

Abstract: A zoom lens includes in order from object side to image side: a positive first lens unit that does not move for zooming; a negative second lens unit that moves during zooming; and a positive N-th lens unit that does not move for zooming, the N-th lens unit being arranged closest to the image side. The first lens unit includes, in order from object side to image side: a negative first sub-lens unit that does not move for focusing; a positive second sub-lens unit that moves along an optical axis during focusing; and a positive third sub-lens unit that does not move for focusing. Focal length of the first lens unit, focal length at wide angle end of the zoom lens, and lateral magnification at wide angle end satisfy predetermined conditions.

Abstract: A zoom lens system comprising a plurality of lens units each being composed of at least one lens element, and comprising, in order from an object side to an image side, 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 positive optical power, and a fifth lens unit having negative optical power, wherein the first lens unit is composed of two or less lens elements, the third lens unit is composed of five or more lens elements, and the condition: 5.0<f1/f3<8.0 (f1: a focal length of the first lens unit, f3: a focal length of the third lens unit) is satisfied.

Abstract: Provided is a zoom lens, 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; and a fourth lens group (G4) having positive refractive power. The first lens group (G1 includes only, in order from the object, a cemented lens of a negative lens (L11) and a positive lens (L12), and a positive meniscus lens (L13) having a convex surface facing the object, an aperture stop (S) for determining brightness is disposed to the object side of the third lens group (G3), and upon zooming, all of the four groups (G1 to G4) move and the aperture stop (S) moves together with the third lens group (G3), and the conditional expression ?dp1>85.0 is satisfied, where ?dp1 denotes an Abbe number of the positive lens (L12), which is disposed closest to the object in the first lens group (G1), at the d-line as a standard.

Abstract: A zoom lens includes a front group, an aperture stop, and a rear group. The front group includes a lens unit configured not to move during zooming and a front variable power lens unit including one or more lens units and configured not to move during zooming. The rear group includes, in order from a magnification conjugate side to a reduction conjugate side, a rear variable power lens unit having one or more lens units and configured to move during zooming, and a lens unit configured not to move during zooming. The aperture stop moves during zooming, and the front group has an auxiliary stop which moves during zooming. A length from a focal point position of the front group to the aperture stop, and imaging magnifications of the rear group, at a wide angle end and a telephoto end, are set to adequate values.

Abstract: A first lens group includes a plano-concave and negative first lens, a catoptric element having a flat object side surface and a flat image side surface, and a first cemented lens, for example. Here, the first cemented lens includes a negative second lens and a positive third lens in order from an object side. A second lens group includes an aperture stop and a positive second cemented lens, for example. The second cemented lens includes a positive fourth lens, a negative fifth lens, and a positive sixth lens in order from the object side. A zoom lens satisfies a conditional expression 1.59<n21<2.20, assuming that a value n21 indicates refractive index of the fourth lens on a side closest to an object in the second lens group.

Abstract: A zoom lens includes, in order from the object side to the image side along its optical path, a first lens unit having a positive refractive power, a second lens unit having a negative refractive power and including a prism reflecting member, 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 distances between the lens units vary during zooming from the wide angle end to the telephoto end, the first lens unit and the third lens unit are located closer to the ray incidence side at the telephoto end than at the wide angle end, the position of the second lens unit is fixed during zooming from the wide angle end to the telephoto end.

Abstract: A zoom lens includes, in order from an object side in an optical axis a first lens group having a positive refractive power, a second lens group having a negative refractive power; a third lens group having a negative refractive power, a fourth lens group having a positive refractive power, a fifth lens group having a positive refractive power, and an aperture stop arranged between the third lens group and the fourth lens group, an interval between the first lens group and the second lens group being increased, an interval between the second lens group and the third lens group being varied, an interval between the third lens group and the fourth lens group being decreased, and an interval between the fourth lens group and the fifth lens group being decreased when changing a magnification from a wide-angle end to a telephoto end.

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: 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 includes a rear lens group having a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, an aperture stop, and a rear lens group having a plurality of lens units in this order from an object side to an image side, wherein the interval between the lens units adjacent to each other varies at the time of zooming, the first lens unit is fixed at the time of zooming, the first lens unit includes a first lens subunit having a negative refractive power, which is fixed at the time of focusing and a second lens subunit having a positive refractive power, which moves at the time of focusing at the time of focusing in this order from the object side to the image side, and the rear lens group includes a lens unit moving in a direction of an optical axis so that an imaging magnification at a telephoto end is larger than an imaging magnification at a wide-angle end.

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 ?5T represents the image formation magnification of the fifth lens group when focusing on infinity at the telephoto end, fw represents the focal length of the entire lens system at the wide angle end, and f3 represents the focal length of the third lens group, formula (Ca): ?5.00?1?(?5T)2??3.30 and formula (H): 0.10<fw/f3<0.50 are satisfied.

Abstract: Provided is a zoom lens, comprising, in order from an object side to an image side: first to fifth lens units having positive, negative, positive, positive, and negative refractive powers, respectively. During zooming, the first, third, and fifth lens units are immovable, and the second and fourth lens units are moved. The fifth lens unit includes a partial unit (L5n) having a negative refractive power, and a partial unit (L5p) having a positive refractive power. An entire lens length (TL), a focal length (ft) of an entire system at a telephoto end, a focal length (f2) of the second lens unit, a focal length (f4) of the fourth lens unit, and a focal length (f5n) of the partial unit (L5n) are set appropriately.

Abstract: The zoom lens substantially consists of a positive first lens group fixed while changing magnification, a negative second lens group which moves from the object side to the image side while changing magnification, a positive third lens group which moves while changing magnification, and a positive fourth lens group which moves from the image side to the object side while changing magnification, and a positive fifth lens group fixed while changing magnification in this order from the object side. A floating system in which the third lens group and the fourth lens group move relative to each other while changing magnification is adopted. The image formation magnification rates of the combined lens group formed by the third lens group and the fourth lens group together and the second lens group simultaneously pass ?1× point while changing magnification from the wide angle end to the telephoto end.

Abstract: A lens system having, in order from an object, at least a first lens group G1 having positive refractive power, and second to fourth lens groups G2 to G4, wherein the first lens group G1 includes a front portion lens group G1a, and a rear portion lens group G1b which is disposed to an image side of the front portion lens group G1a with an air distance therebetween, and performs focusing by shifting the rear portion lens group G1b in the optical axis direction, and the fourth lens group G4 includes, in order from the object, a negative lens and a positive lens (cemented negative lens L41), a negative lens L42, and an aperture stop S, and is fixed in the optical axis direction with respect to an image plane I upon zooming from a wide angle end state to a telephoto end state.

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 zoom lens includes, 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 negative refractive power; and a fifth lens group having a negative refractive power. During zooming from a wide-angle end state to a telephoto end state, air spacing between the first and second lens groups increases, air spacing between the second and third lens groups decreases, spacing between the third and fourth lens groups changes, and spacing between the fourth and fifth lens groups changes. Thus, all the lens groups are moved in an optical axis direction. The zoom lens satisfies the following Conditional Expression (1). 1.0<?5w?4.0??(1) Here, ?5w is a lateral magnification of the fifth lens group at a wide-angle end.

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. When focusing, only the fifth lens group is shifted. The fifth lens group has at least one negative lens and at least one positive lens.

Abstract: 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<?3p<110??(1).

Abstract: A projector for projecting light onto a projection surface includes a first group (1) with a negative meniscus, a second group (2) with positive refractive power, a third group (3) with a single lens, a fourth group (4) with a lens with positive refractive power, and a field lens (5) with positive refractive power, such that the light passes through the projection objective from the fourth to the first group. In order to be provide a high image quality with a small number of optical components and the smallest dimensions, the projector is configured so the common focal width of the fourth group (4) and the field lens (5) is smaller than twice the image circle diameter (9) of the projection objective and the maximum free diameter (8) is smaller than the overall focal width, and in particular smaller than 0.8 times the overall focal width of the projection objective.

Abstract: A zoom lens comprises a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, and a rear group including at least two lens units and having a positive refractive power as a whole, in order from an object side to an image side. An interval of each of the lens units changes in a zoom operation, the rear group includes a lens unit R having a positive refractive power at the most image side, the lens unit R includes a lens having a concave surface at the image side and having an aspherical surface shape where a negative refractive power becomes stronger with increasing distance from an optical axis, and focal lengths f1, fR, and fw of the first lens unit, the lens unit R, and a whole system at a wide-angle end, respectively, are appropriately set.

Abstract: A zoom lens includes in order from an object side: a first lens unit having a positive refractive power which does not move for zooming; a second lens unit having a negative refractive power which moves during zooming; a third lens unit having a positive refractive power which moves during zooming; and a fourth lens unit having a positive refractive power which does not move for zooming, the third lens unit moving to an image side and then to the object side for zooming from a wide angle end to a telephoto end, in which a focal length (f1) of the first lens unit, a focal length (f2) of the second lens unit, a focal length (f3) of the third lens unit, and a lateral magnification (?3w) of the third lens unit at the wide angle end when a ray enters from infinity are appropriately set.

Abstract: A zoom lens includes: a first lens group having a positive refractive power and including a plurality of lenses, 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 including one lens, and a fifth lens group having a positive refractive power and including one lens. The first through fifth lens groups are subsequently arranged from an object side. An interval between neighboring lens groups changes during zooming from a wide angle position to a telephoto position. The zoom lens satisfies the following inequality, 0.4?n1?n2?0.7, where “n1” denotes a refractive index of a first lens from the object side in the first lens group, and “n2” denotes a refractive index of the second lens from the object side in the first lens group.