Fujifilm Corporation

Fujinon Corporation

Daiki Kawamura

Michio Cho

Taiga Noda

Tetsuya Ori

Motoari Ota

Ryoko Tomioka

A zoom lens includes a negative first lens group, a positive second lens group, and a subsequent lens group in order from an object side. A focusing lens group closer to an image side than the first lens group moves during focusing. The first lens group consists of a first-a lens group and a first-b lens group in order from the object side. Assuming that an average of refractive indices of the negative lenses of the first-a lens group is Nd1ave, a focal length of the focusing lens group is ff, and a focal length of the first lens group is f1, Conditional Expression (1) of 1.73<Nd1ave<1.95 and Conditional Expression (2) of 1<|ff/f1|<3 are satisfied.

Zoom lens and imaging apparatus

An imaging lens includes, in order from the object side, a first lens group that has a negative refractive power and a second lens group that has a positive refractive power. During focusing, only the second lens group moves. The first lens group includes three negative lenses successively in order from a position closest to the object side. Assuming that an open F number is FNo, a maximum half angle of view is ω, a back focal length is Bf, and a focal length of the whole system f, the imaging lens satisfies 0.8<FNo/tan ω<1.9 and 0.3<Bf/(f×tan ω)<1.2.

Imaging lens and imaging apparatus

An imaging lens includes a positive first lens group and a second lens group, which are continuous in order from the position closest to the object side, as lens groups. During focusing, the distance between the first lens group and the second lens group changes. A stop is disposed closer to the image side than a lens which is second from the object side. A combined refractive power of all lenses closer to the object side than the stop is positive. The imaging lens includes an LA positive lens and an LB positive lens that satisfy a predetermined conditional expression at a position closer to the object side than the stop. An Abbe number of the LB positive lens is the maximum among Abbe numbers of all positive lenses closer to the object side than the stop.

An imaging lens includes, successively in order from a position closest to an object side, a positive first lens group that does not move during focusing, a stop, and a positive second lens group that moves during focusing. The second lens group consists of all lenses that integrally move during focusing. The imaging lens satisfies predetermined conditional expressions.

The zoom lens includes, as lens groups, in order from the object side, only a first lens group having a positive power, a second lens group having a negative power, a third lens group having a positive power, a fourth lens group having a negative power, and a fifth lens group having a positive power. An aperture stop is disposed between a lens surface closest to the image side in the second lens group and a lens surface closest to the object side in the fourth lens group. During zooming, at least the first lens group, the second lens group, the third lens group, and the fourth lens group move. The first lens group consists of a negative lens, a positive lens, and a positive lens in order from the object side. The zoom lens satisfies predetermined conditional expressions.

A zoom lens includes a negative first lens group, a positive second lens group, and a subsequent lens group in order from an object side. A focusing lens group closer to an image side than the first lens group moves during focusing. The first lens group consists of a first-a lens group and a first-b lens group in order from the object side. Assuming that an average of refractive indices of the negative lenses of the first-a lens group is Nd1ave, a focal length of the focusing lens group is ff, and a focal length of the first lens group is f1, Conditional Expression (1) of 1.73&#x3c;Nd1ave&#x3c;1.95 and Conditional Expression (2) of 1&#x3c;|ff/f1|&#x3c;3 are satisfied.

The imaging lens comprises, successively in order from the object side, a positive first lens group that does not move during focusing, a second lens group that moves during focusing, a stop, and a positive third lens group that consists of all lenses moving integrally with the second lens group during focusing. The composite focal length of the second lens group and the third lens group is positive. The first lens group includes four or more positive lenses and three or more negative lenses. The imaging lens satisfies predetermined conditional expressions.

The lens device includes an imaging lens and a controller. The imaging lens includes a focusing lens group which moves during focusing and an aberration correction lens group having a refractive power lower than a refractive power of the focusing lens group having the lowest refractive power. The controller adjusts a position of the aberration correction lens group relative to the focusing lens group of which focus sensitivity is maximized according to a changed condition. A predetermined conditional expression related to the focus sensitivity of the focusing lens group is satisfied.

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Saitama-ken, Japan

Daiki Kawamura