A zoom lens consists of, 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 unit that includes a plurality of lens units. All lens units move during zooming, and a distance between adjacent lens units changes. The third lens unit includes, in order from the object side to the image side, a first subunit having a positive refractive power, a second subunit having a positive refractive power, and a third subunit having a positive refractive power. The second subunit includes a negative lens and a positive lens. The second subunit moves in a direction having a component orthogonal to an optical axis during an image stabilization. A predetermined condition is satisfied.

A variable magnification optical system includes a positive first lens group disposed at a most object side, a negative intermediate group disposed at an image side of the first lens group, a positive focusing group disposed at an image side of the intermediate group, and a positive image side group disposed at an image side of the focusing group. Upon varying magnification, a distance between the first lens group and the intermediate group, a distance between the intermediate group and the focusing group and a distance between the focusing group and the image side group are varied; and the image side group includes, in order from an object side, a positive A group, a negative B group satisfying a predetermined conditional expression with respect to the A group, and a C group, whereby excellent optical performance, high speed focusing, and other advantages are achieved.

A zoom lens comprising, 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 positive refractive power an interval between adjacent lens units changing and the first to fourth lens units moving during zooming. An image blur is corrected by moving a sub-unit having a negative refractive power as a whole in the third lens unit orthogonally to an optical axis. A predetermined conditions are satisfied.

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) are arranged in order from an object, and a distance between the first lens group (G1) and the second lens group (G2), a distance between the second lens group (G2) and the third lens group (G3), a distance between the third lens group (G3) and the fourth lens group (G4), and a distance between the fourth lens group (G4) and the fifth lens group (G5) change upon zooming, and a lens group arranged closest to an image is approximately fixed against an image surface (I) upon zooming, and the third lens group (G3) moves along the optical axis upon focusing, and the following expression (1) is satisfied.
0.480<f3/ft<4.000   (1)

A variable magnification optical system includes: a first lens group having a positive refractive power and arranged closest to an object; a negative lens group having a negative refractive power and arranged closer to an image than the first lens group; a positive lens group which has a positive refractive power, which includes at least one lens that moves integrally with an aperture stop, and which is arranged closer to the image than the negative lens group; and a focusing group arranged between the negative lens group and the positive lens group, wherein when varying magnification, the first lens group moves with respect to an image plane, the distance between the first lens group and the negative lens group is changed, and the distance between the negative lens group and the positive lens group is changed, wherein when focusing, the distance between the focusing group and a lens arranged at a position to face an object-side of the focusing group is changed, and the distance between the focusing group and a lens arranged at a position to face an image-side of the focusing group is changed, wherein the focusing group is constituted by a single lens component, wherein the positive lens group is constituted by a front group having a positive refractive power and a rear group having a negative refractive power, and the distance between the front group and the rear group is the largest air distance among air distances in the positive lens group, and wherein the rear group is constituted by two lens components.

A variable magnification optical system comprising, 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, and a rear lens group; upon varying magnification, the first lens group being fixed with respect to the image plane and each distance between the neighboring lens groups being varied; the rear lens group comprising a focusing lens group which is moved upon carrying out focusing; and the predetermined conditional expressions being satisfied, whereby it is possible to suppress superbly variations in aberrations upon varying the magnification.

A zoom lens module includes first to eighth lens elements sequentially arranged from an object end to an image end. The number of lens elements with refractive power in the zoom lens module is eight. The first lens element and the second lens element form a first lens element group. The third lens element and the fourth lens element form a second lens element group. The fifth lens element and the sixth lens element form a third lens element group. The seventh lens element and the eighth lens element form a fourth lens element group. The first lens element group and the fourth lens element group remain fixed during zooming. The second lens element group and the third lens element group move during zooming.

A zoom lens includes, in order from an object side to an image side, a first lens unit having a positive refractive power, a plurality of zooming lens units configured to move along an optical axis in zooming and including a lens unit having a negative refractive power, and a final lens unit having a positive refractive power. A distance between each pair of adjacent lens units changes in zooming. The first lens unit includes, in order from the object side to the image side, a first subunit having a negative refractive power, a second subunit having a negative refractive power, and at least one subsequent subunit, a distance between each pair of adjacent subunits changing for focusing. The second subunit is configured to move along the optical axis for focusing. A predetermined condition is satisfied.

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, and a subsequent unit. The first lens unit is configured not to move for zooming. A distance between each pair of adjacent lens units changes in zooming. A predetermined condition is satisfied.

A zoom lens includes, in order from an object side to an image side, a first lens unit having a positive refractive power, a plurality of lens units which move in zooming, and a final lens unit having a positive refractive power, an interval between each pair of adjacent lens units changing in zooming, the plurality of lens units including a lens unit having a negative refractive power, the first lens unit including a negative lens and a positive lens, at least a part of the first lens unit moving for focusing, the first lens unit including a negative lens made of a material satisfying inequalities defined by a refractive index, an Abbe number, and a partial dispersion ratio, and the zoom lens satifying an inequality defined by a maximum value of an Abbe number of at least one positive lens of the first lens unit.