This optical system (OL) comprises a front group (GA), an aperture stop (S), and a rear group (GB) that are arranged in order from the object side along an optical axis. The rear group (GB) has a focusing lens group (GF1) disposed closest to the object side in the rear group (GB) and having negative refractive power, during focusing, the focusing lens group moves along the optical axis, and the spacing between adjacent lens groups changes, and the following conditional expression is satisfied. 0.50<ST/TL<0.95, where ST is the distance on the optical axis from the aperture stop (S) to an image surface (I), and TL is the total length of the optical system (OL).

An optical imaging lens includes first to third lens element groups in sequence along an optical axis from an object side to an image side. The first lens element group includes at least two lens elements. The second lens element group includes at least two lens elements. The third lens element group includes at least two lens elements. When the optical imaging lens is zoomed, at least one lens element group is moved toward a direction of the object side or the image side along the optical axis.

An optical system includes a first unit having positive refractive power, a second unit having positive or negative refractive power and configured to move in focusing, and a third unit having negative refractive power in order from an object side to an image side. A distance between adjacent two of the units changes in focusing. When a distance on an optical axis from a lens surface closest to the object side to a lens surface closest to the image side is TL, a distance on the optical axis from a lens surface closest to the object side to a lens surface closest to the image side in the third unit is TL3, a sum of thicknesses, on the optical axis, of lenses in the third unit is SD3, and the largest of the thicknesses of the lenses in the third unit is DM3, the optical system satisfies predetermined conditional inequalities.

A variable magnification optical system consists of, in order from an object side to an image side, a first lens group, a second lens group, and a subsequent lens group. The variable magnification optical system satisfies a predetermined conditional expression for a partial dispersion ratio related to F line, C line, and a wavelength of 1970.09 nm, a d-line back focus of the variable magnification optical system at a telephoto end, a back focus in any one wavelength from a wavelength of 1300 nm to a wavelength of 2325.42 nm at the telephoto end, and a d-line focal length of the variable magnification optical system at the telephoto end.

A variable magnification optical system includes, in order from an object side, a first lens group having positive refractive power; a second lens group having negative refractive power; and a third lens group having positive refractive power; upon zooming from a wide-angle end state to a telephoto end state, a distance between the first lens group and the second lens group and a distance between the second lens group and the third lens group being varied. The variable magnification optical system further includes a V lens group GV having negative refractive power and being moved to have a component in a direction perpendicular to the optical axis, and an F lens group GF having positive refractive power and being moved along the optical axis upon focusing from an infinitely distant object to a close object, the V lens group GV being disposed on the more object side than the F lens group GF. Thereby, it is possible to provide the compact variable magnification optical system with a high zoom ratio and high performance, an optical apparatus therewith and a method for manufacturing the variable magnification optical system.

A zoom lens includes a first lens group, a second lens group, a third lens group, and a fourth lens group that are sequentially arranged from an object side to an image side along an optical axis. The first lens group and the third lens group are fastened, and the second lens group and the fourth lens group move along the optical axis. A first lens from the object side in the first lens group is a biconvex lens, and at least two lenses from the object side in the first lens group are glass lenses. A maximum clear aperture diameter of the zoom lens has the following relationship of 4 mm≤φ≤12 mm, where p is the maximum clear aperture diameter of the zoom lens.

An optical system (OL) formed from a preceding lens group (GA) having a negative refractive power, and a succeeding lens group (GB) having a positive refractive power, the lens groups being arranged in order from the object side along the optical axis. The succeeding lens group (GB) has: a focusing group (GF) having a positive refractive power, the focusing group (GF) being positioned furthest toward the object side of the succeeding lens group (GB); and an image-side group (GC) positioned further toward the image side than the focusing group (GF). During focusing from an infinitely distant object to a short-distance object, the focusing group (GF) moves toward the image side along the optical axis and satisfies the following conditional expression.

0.78<fB/fC<1.00

In this conditional expression,

fB is the focal distance of the succeeding lens group GB, and

fC is the focal distance of the image-side group GC.

A zoom lens consists of four or more lens units including, in order from an object side to an image side, first, second, and third lens units having positive, negative, and positive refractive powers, respectively. During zooming from a wide-angle end to a telephoto end, the first lens unit moves, a distance between the first lens unit and the second lens unit is widened, and a distance between the second lens unit and the third lens unit is narrowed. The first lens unit consists of a single positive lens, the second lens unit includes three single lens elements, each having a negative refractive power, arranged continuously in order from the object side to the image side, predetermined conditions are 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, a third lens unit having a positive refractive power, and one or more rear lens units. The first lens unit does not move for zooming. An interval between each pair of adjacent lens units changes in zooming. The first lens unit includes a positive lens made of material with an Abbe number less than 30. A predetermined condition is satisfied.

A variable magnification optical system (ZL) comprises a preceding lens group (GA) having negative refractive power and a succeeding lens group (GB) having positive refractive power, which are arranged in order from the object side along an optical axis. The succeeding lens group (GB) has a focusing group (GF) and an image-side group (GC) disposed closer to the image side than the focusing group (GF), the focusing group (GF) moves to the image side along the optical axis from focusing on an object at infinity to focusing on a close-distance object, and the following conditional expression is satisfied.

1.80<fF/fBaw

FNow<3.40 where fF is the focal length of the focusing group (GF), fBaw is the focal length in the wide-angle end state of an image-side lens group (GBa) composed of lenses disposed on the image side from the focusing group (GF), and FNow is the F-number of the variable magnification optical system (ZL) in the wide-angle end state.