Abstract: A zoom lens comprises 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 rear group including at least one lens unit, in order from an object side to an image side. Each of the lens units is configured to move so that a total lens length at a wide-angle end is longer than that at a telephoto end to perform a zoom operation. A movement amount M1 of the first lens unit at the wide-angle end and the telephoto end with respect to an imaging surface, a focal length f1 of the first lens unit, and focal lengths fw and ft of a whole system at the wide-angle end and the telephoto end are appropriately set.

Abstract: A zoom lens includes, in order from the object side to the image side, a positive refractive first lens unit, a negative refractive second lens unit, a positive refractive third lens unit, and a rear group including one or more lens units. The first lens unit consists of a negative lens and a positive lens. The first to third lens units and the lens units constituting the rear group move at a time of zooming. The first and third lens units move relative to the image plane in such a way that their respective positions at the telephoto end are displaced toward the object side from their respective positions at the wide angle end. The focal lengths f1, f2 of the first and second lens units and the focal lengths fw, ft of the whole system at the wide angle end and at the telephoto end are arranged appropriately.

Abstract: Provided is a zoom lens system including, 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 prism for bending an optical path; and a rear group including a plurality of lens units, in which the first lens unit is moved to the object side while the second lens unit is moved to the image side with respect to an imaging plane at a telephoto end compared to at a wide angle end, and movement amounts M1 and M2 of the first lens unit and the second lens unit with respect to an image plane in zooming from the wide angle end to the telephoto end, a focal length f2 of the second lens unit, and a focal length ft of an entire system at the telephoto end are respectively set appropriately.

Abstract: A zoom lens includes a first, third and fourth lens group of positive refracting power, a second lens group of negative refracting power, wherein, during zooming from a wide-angle end to a telephoto end, at least the first lens group moves, wherein the third lens group includes, a first lens sub-group of positive refracting power and a second lens sub-group of negative refracting power, wherein the second lens sub-group includes a single negative lens, wherein the first lens sub-group of the third lens group is moved to keep a perpendicular component relative to an optical axis to correct image blur to be produced when the zoom lens vibrates, and wherein, when a focal length of the first lens group is denoted by f1 and the focal length of the whole system at the wide-angle end is denoted by fw, a conditional expression 10.0<f1/fw<20.0 is satisfied.

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 rear group including at least one lens unit. For zooming from a wide angle end to a telephoto end, the first lens unit moves to the object side, the second lens unit moves to the image side, and the third lens unit moves to the object side. Moving amounts of the first lens unit, the second lens unit, and the third lens unit for zooming from the wide angle end to the telephoto end and focal lengths of the second lens unit and the third lens unit are set based on predetermined conditions.

Abstract: A zoom lens includes, in order from an object side to an image side, a first lens unit of negative refractive power, a second lens unit of positive refractive power, and a third lens unit of positive refractive power. The zoom lens changes the distances between the lens units during zooming. The following condition is satisfied: 0.3<|f1/fT<0.5 2.3<|f1/fw<3.5, where f1 is a focal length of the first lens unit, fT is a focal length of the zoom lens at a telephoto end, and fw is a focal length of the zoom lens at a wide-angle end.

Abstract: A zoom lens includes a first, third and fourth lens group of positive refracting power, a second lens group of negative refracting power, wherein, during zooming from a wide-angle end to a telephoto end, at least the first lens group moves, wherein the third lens group includes, a first lens sub-group of positive refracting power and a second lens sub-group of negative refracting power, wherein the second lens sub-group includes a single negative lens, wherein the first lens sub-group of the third lens group is moved to keep a perpendicular component relative to an optical axis to correct image blur to be produced when the zoom lens vibrates, and wherein, when a focal length of the first lens group is denoted by f1 and the focal length of the whole system at the wide-angle end is denoted by fw, a conditional expression 10.0<f1/fw<20.0 is satisfied.

Abstract: A zoom lens includes, in order from an object side to an image side, first and second lens units respectively having positive and negative refractive powers, a reflecting prism for bending an optical path, and a rear lens group including lens units. At least the first and second lens units move for zooming. During retraction into a storage state, the prism moves to a position different from a position in an image taking state, and at least a part of the first and second lens units is retracted into a space formed by movement of the prism. Thicknesses of the first and second lens units, a moving amount of the first lens unit during zooming from a wide angle end to a telephoto end, a focal length of the first lens unit, and a focal length of the entire zoom lens at the telephoto end are set properly.

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 rear group including at least one lens unit. For zooming from a wide angle end to a telephoto end, the first lens unit moves to the object side, the second lens unit moves to the image side, and the third lens unit moves to the object side. Moving amounts of the first lens unit, the second lens unit, and the third lens unit for zooming from the wide angle end to the telephoto end and focal lengths of the second lens unit and the third lens unit are set based on predetermined conditions.

Abstract: A zoom lens includes, in order from an object side to an image side, a first lens unit of negative refractive power, a second lens unit of positive refractive power, and a third lens unit of positive refractive power. The zoom lens changes the distances between the lens units during zooming. The following condition is satisfied: 0.3<|f1 |/fT<0.5, where f1 is a focal length of the first lens unit, and fT is a focal length of the zoom lens at a telephoto end.

Abstract: A zoom lens comprises 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 rear group including at least one lens unit, in order from an object side to an image side. Each of the lens units is configured to move so that a total lens length at a wide-angle end is longer than that at a telephoto end to perform a zoom operation. A movement amount M1 of the first lens unit at the wide-angle end and the telephoto end with respect to an imaging surface, a focal length f1 of the first lens unit, and focal lengths fw and ft of a whole system at the wide-angle end and the telephoto end are appropriately set.

Abstract: A zoom lens includes, in order from an object side to an image side, a first lens unit of negative refractive power, a second lens unit of positive refractive power, and a third lens unit of positive refractive power. The zoom lens changes the distances between the lens units during zooming. The following condition is satisfied: 0.3<|f1/fT<0.5 2.3<|f1/fw<3.5, where f1 is a focal length of the first lens unit, fT is a focal length of the zoom lens at a telephoto end, and fw is a focal length of the zoom lens at a wide-angle end.

Abstract: A zoom lens includes 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 positive refractive power. The first and third lens units are movable such that they are located closer to the object side at a telephoto end than at a wide-angle end. The fourth lens unit is movable with a locus convex towards the object side. A distance between the first and second lens units at the telephoto end, a distance between the second and third lens units at the telephoto end, a focal length of the first lens unit, a focal length of the second lens unit, and a focal length of the third lens unit, and a focal length of the entire zoom lens at the wide-angle end are appropriately set.

Abstract: A zoom lens system that performs zooming by moving lens units includes, in the following order from an object side towards image side, a first lens unit having positive refractive power and movable along a locus convex towards the image side during zooming from a wide-angle end to telephoto end, a second lens unit having negative refractive power, an aperture stop movable independently of the lens units, and third and fourth lens units having positive refractive powers. The following conditions are satisfied: ?0.6<f2/f3<?0.4 ?0.5<MS/M3<0.9 where MS and M3 respectively indicate moving distances of the aperture stop and third lens unit along an optical axis, and f2 and f3 respectively indicate focal lengths of the second and third lens units, each moving distance being a positive sign if directed towards the image side or a negative sign if directed towards the object side.

Abstract: A zoom lens includes 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 positive refractive power. The first and third lens units are movable such that they are located closer to the object side at a telephoto end than at a wide-angle end. The fourth lens unit is movable with a locus convex towards the object side. A distance between the first and second lens units at the telephoto end, a distance between the second and third lens units at the telephoto end, a focal length of the first lens unit, a focal length of the second lens unit, and a focal length of the third lens unit, and a focal length of the entire zoom lens at the wide-angle end are appropriately set.

Abstract: A zoom lens includes, in order from an object side to an image side, a first lens unit of negative refractive power, a second lens unit of positive refractive power, and a third lens unit of positive refractive power. The zoom lens changes the distances between the lens units during zooming. The following condition is satisfied: 0.3<|f1 |/fT<0.5, where f1 is a focal length of the first lens unit, and fT is a focal length of the zoom lens at a telephoto end.

Abstract: A zoom lens includes a first, third and fourth lens group of positive refracting power, a second lens group of negative refracting power, wherein, during zooming from a wide-angle end to a telephoto end, at least the first lens group moves, wherein the third lens group includes, a first lens sub-group of positive refracting power and a second lens sub-group of negative refracting power, wherein the second lens sub-group includes a single negative lens, wherein the first lens sub-group of the third lens group is moved to keep a perpendicular component relative to an optical axis to correct image blur to be produced when the zoom lens vibrates, and wherein, when a focal length of the first lens group is denoted by f1 and the focal length of the whole system at the wide-angle end is denoted by fw, a conditional expression 10.0<f1/fw<20.0 is satisfied.

Abstract: A zoom lens system that performs zooming by moving lens units includes, in the following order from an object side towards image side, a first lens unit having positive refractive power and movable along a locus convex towards the image side during zooming from a wide-angle end to telephoto end, a second lens unit having negative refractive power, an aperture stop movable independently of the lens units, and third and fourth lens units having positive refractive powers. The following conditions are satisfied: ?0.6<f2/f3<?0.4 ?0.5<MS/M3<0.9 where MS and M3 respectively indicate moving distances of the aperture stop and third lens unit along an optical axis, and f2 and f3 respectively indicate focal lengths of the second and third lens units, each moving distance being a positive sign if directed towards the image side or a negative sign if directed towards the object side.

Abstract: A zoom lens includes, in order from an object side to an image side, a first lens unit of negative refractive power, a second lens unit of positive refractive power, and a third lens unit of positive refractive power. The first lens unit moves in a locus convex toward the image side and the second lens unit moves toward the object side during zooming from a wide-angle end to a telephoto end. The object side principal point position of the first lens unit is within the first lens unit. The movement locus of the image side principal point position of the first lens unit during zooming from the wide-angle end to the telephoto end intersects with the movement locus of the object side principal point position of the second lens unit 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 of negative refractive power, a second lens unit of positive refractive power, and a third lens unit of positive refractive power. The first lens unit moves in a locus convex toward the image side and the second lens unit moves toward the object side during zooming from a wide-angle end to a telephoto end. The object side principal point position of the first lens unit is within the first lens unit. The movement locus of the image side principal point position of the first lens unit during zooming from the wide-angle end to the telephoto end intersects with the movement locus of the object side principal point position of the second lens unit during zooming from the wide-angle end to the telephoto end.