The imaging lens consists of, in order from the object side, a first lens group, an aperture stop, a second lens group having a positive refractive power. During focusing from a distant object to a close-range object, the first lens group remains stationary, and the aperture stop and the second lens group integrally move to the object side. The imaging lens satisfies predetermined conditional expressions relating to a focal length of the whole system, a focal length of the first lens group, a principal point position of the second lens group, a focal length of the second lens group, a back focal length, and the like.

A zoom lens includes, in order from an object side to an image side, a first lens unit having negative refractive power, and a rear group including two or more lens units, and an aperture stop. The rear group includes an image stabilizing unit having negative refractive power and configured to move with a component in a direction orthogonal to an optical axis during image stabilization, and a focus unit disposed on the object side of the image stabilizing unit. A distance between adjacent lens units changes during zooming. A predetermined inequality is satisfied.

A zoom lens includes, 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 an aperture stop. A distance between adjacent lens units changes during zooming. The first lens unit includes at least three or four lens elements. Predetermined inequalities are satisfied.

A zoom lens includes a first lens group and a second lens group. A relative movement between the first lens group and the second lens group is allowed, whereby the zoom lens zooms between a wide-angle end and a telephoto end. While the zoom lens is switched from the wide-angle end toward an intermediate state, the first lens group is moved toward the image side. While the zoom lens is switched from the intermediate state toward the telephoto end, the first lens group is moved toward the object side.

A zoom lens includes, in order from an object side to an image side, a front group including a plurality of lens units, an image stabilizing unit having negative refractive power, and a rear group including one or more lens units. Each distance between adjacent lens units changes during zooming. The front group has a focus unit and an aperture stop. Predetermined inequalities are satisfied.

A magnification-variable optical system having a small size, a wide angle of view, and high optical performance, an optical apparatus including the magnification-variable optical system, and a method for manufacturing the magnification-variable optical system are provided.

A magnification-variable optical system ZL used for an optical apparatus such as a camera 1 includes a first lens group G1 having a negative refractive power and including at least two lenses, and a rear group GR including at least one lens group disposed on an image side of the first lens group G1, and is configured so that a distance between lens groups adjacent to each other changes at magnification change and a condition expressed by predetermined condition expressions is satisfied.

At least one embodiment of an optical system includes, in order from an object side to an image side, a front unit including a plurality of lenses, an aperture stop, and a rear unit having a positive refractive power. In at least one embodiment, four negative lenses are consecutively arranged from a side of the front unit closest to the object side, and a focal length of the front unit and a focal length of the rear unit are appropriately set.

A zoom lens system for providing high quality images with higher resolution includes a first lens group (110), an aperture stop (120), and a second lens group (130). The first lens group has a positive or negative refractive power, and includes at least two lens elements having a negative refractive power and at least on lens element having a positive refractive power. The second lens group has a positive refractive power. A distance between a first and second lens group is not fixed.

An optical system (LS) includes lenses (L22,L23) satisfying the following conditional expressions,
?dLZ<35.0, and
0.702<?gFLZ+(0.00316??dLZ), where ?dLZ: Abbe number of the lens with reference to d-line, and ?gFLZ: a partial dispersion ratio of the lens, wherein ?gFLZ is defined by the following expression,
?gFLZ=(ngLZ?nFLZ)/(nFLZ?nCLZ). wherein a refractive index of the lens with reference to g-line is ngLZ, a refractive index of the lens with reference to F-line is nFLZ, and a refractive index of the lens with reference to C-line is nCLZ.

A zoom lens system includes, in order from the object side to the image side, a first lens group having negative power and a second lens group having positive power. The first lens group includes at least two negative lenses. When zooming, one of the first lens group and the second lens group is fixed relative to the imaging surface, and the other moves along an optical axis to change an angle of view.