Nikon Corporation

Kosuke Machida

Takeshi Suzuki

Takeru Uehara

Atsushi Shibayama

Tsuneo Watanabe

Kenichi Kitano

Mizuki Wayu

Osamu Gomibuchi

Ichiro Imaei

Makoto Horikoshi

A variable magnification optical system comprising a plurality of lens groups and, upon varying a magnification, distances between respective lens groups in the plurality of lens groups being varied. The plurality of lens groups comprises an object side focusing lens group which is moved upon carrying out focusing and at least one image side focusing lens group disposed in a more image side than the object side focusing lens group and moved with a trajectory differing from that of the object side focusing lens group, upon carrying out focusing. The predetermined conditional expressions are satisfied. Thus, variations in aberrations upon varying magnification from the wide angle end state to the telephoto end state as well as variations in aberrations upon carrying out focusing from an infinite distance object to a close distance object can be suppressed superbly.

Variable magnification optical system, optical apparatus, and method for producing variable magnification optical system

A zoom optical system comprises, in order from an object: a front lens group (GFS) having a positive refractive power; an M1 lens group (GM) having a negative refractive power; an M2 lens group (GM) having a positive refractive power; and an RN lens group (GRN) having a negative refractive power, wherein upon zooming, distances between the front lens group and the M1 lens group, between the M1 lens group and the M2 lens group, and between the M2 lens group and the RN lens group change, upon focusing from an infinite distant object to a short distant object, the RN lens group moves, the RN lens group comprises at least one lens having a positive refractive power, and at least one lens having a negative refractive power, and following conditional expressions are satisfied, 2.70<fFP/(−fFN)<4.50, 0.25<(−fF)/f1<0.45, where fFP: a focal length of a lens having a strongest positive refractive power in the RN lens group, fFN: a focal length of a lens having a strongest negative refractive power in the RN lens group, fF: a focal length of the RN lens group, and f1: a focal length of the front lens group.

Zoom optical system, optical apparatus, imaging apparatus and method for manufacturing the zoom optical system

A variable magnification optical system that comprises a first lens group having negative refractive power, a first intermediate lens group having positive refractive power, a second intermediate lens group, and a rear lens group having at least one focusing lens group which is moved upon carrying out focusing from an infinitely distant object to a closely distant object. The variable magnification optical system is constructed such that, upon varying a magnification from a wide angle end state to a telephoto end state, the first lens group is moved along the optical axis, a distance between the first lens group and the first intermediate lens group is varied, a distance between the first intermediate lens group and the second intermediate lens group is varied, a distance between the second intermediate lens group and the rear lens group is varied, and predetermined conditional expressions are satisfied.

A zoom optical system (ZL) comprises, in order from an object, a first lens group (G) having a positive refractive power, a second lens group (G) having a negative refractive power, a third lens group (G) having a positive refractive power, a fourth lens group (G) having a positive refractive power and a succeeding lens group (GR). In the zoom optical system, upon zooming, distances between adjacent lens groups change, and the succeeding lens group (GR) includes a plurality of focusing lens groups that have positive refractive powers and move upon focusing.

Zoom optical system, optical apparatus and method for manufacturing the zoom optical system

A variable power optical system includes a plurality of lens groups. During variable magnification, an interval between adjacent lens groups changes. The plurality of lens groups include: a first focusing lens group that moves during focusing; and a second focusing lens group that is disposed more toward an imaging surface side than the first focusing lens group and that moves along a different trajectory than the first focusing lens group during focusing. The first focusing lens group and the second focusing lens group both have a negative refractive power. The first focusing lens group or the second focusing lens group includes at least one lens having a positive refractive power, and is configured so as to satisfy the following condition: 1.40<fFP/(−fFN)<3.50.

A variable power optical system (ZL ()) includes a plurality of lens groups (G-G). During variable magnification, an interval between adjacent lens groups changes. The plurality of lens groups include: a first focusing lens group (G) that moves during focusing; and a second focusing lens group (G) that is disposed more toward an imaging surface side than the first focusing lens group and that moves along a different trajectory than the first focusing lens group during focusing. The first focusing lens group and the second focusing lens group both have a negative refractive power. The plurality of lens groups satisfy the following condition: 0.40<fF1/fF2<3.50 (wherein fF1 is the focal distance of the first focusing lens group, and fF2 is the focal distance of the second focusing lens group).

A zoom optical system (ZL) comprises, in order from an object: a first lens group (G) having a positive refractive power; a second lens group (G) having a negative refractive power; a third lens group (G) having a positive refractive power; and a subsequent lens group (GR), wherein upon zooming, a distance between the first lens group (G) and the second lens group (G) changes, a distance between the second lens group (G) and the third lens group (G) changes, and a distance between the third lens group (G) and the subsequent lens group (GR) changes, the subsequent lens group (GR) comprises a focusing lens group that moves upon focusing, and the second lens group (G) comprises a partial group that satisfies following conditional expressions, 1.40<fvr/f2<2.30, 1.80<f1/fw<3.50 where fvr: a focal length of the partial group, f2: a focal length of the second lens group (G), f1: a focal length of the first lens group (G), and fw: a focal length of the zoom optical system (ZL) in a wide-angle end state.

Zoom optical system, optical apparatus and imaging apparatus using the zoom optical system, and method for manufacturing the zoom optical system

A zoom optical system comprises, in order from an object: a front lens group (GFS) having a positive refractive power; an Mlens group (GM) having a negative refractive power; an Mlens group (GM) having a positive refractive power; and an RN lens group (GRN) having a negative refractive power, wherein upon zooming, distances between the front lens group and the Mlens group, between the Mlens group and the Mlens group, and between the Mlens group and the RN lens group change, upon focusing from an infinite distant object to a short distant object, the RN lens group moves, and the Mlens group comprises an A lens group that satisfies a following conditional expression, 1.10<fvr/fTM2<2.00, where, fvr: a focal length of the A lens group, and fTM2: a focal length of the Mlens group in a telephoto end state.

A variable magnification optical system comprising, in order from an object side, a first lens group having negative refractive power, a first intermediate lens group having positive refractive power, a second intermediate lens group having negative refractive power and a rear lens group; upon varying a magnification from a wide angle end state to a telephoto end state, a distance between the first lens group and the first intermediate lens group being varied, a distance between the first intermediate lens group and the second intermediate lens group being varied, and a distance between the second intermediate lens group and the rear lens group being varied; the rear lens group comprising at least one focusing lens group which is moved upon carrying out focusing from an infinitely distant object to a closely distant object; and predetermined conditional expressions being satisfied, thereby the focusing lens group(s) being reduced in weight.

A zoom optical system comprises, in order from an object: a first lens group (G) having positive refractive power; a second lens group (G) having negative refractive power; and a subsequent group (GR) including at least one lens group. Upon zooming, distances between the first lens group (G) and the second lens group (G) and between the second lens group (G) and the subsequent group (GR) change. The subsequent group (GR) comprises a focusing group (Gfc) having negative refractive power for focusing. The first lens group (G) comprises a 1-1st lens that has positive refractive power and is disposed closest to the object. A following conditional expression is satisfied:0.20<1/<0.85

A variable magnification optical system comprises, in order from an object side, a first lens group Ghaving positive refractive power, a second lens group Ghaving negative refractive power, a third lens group Ghaving positive refractive power and a fourth lens group Ghaving negative refractive power; upon varying a magnification, a distance between the first lens group Gand the second lens group Gbeing varied, a distance between the second lens group Gand the third lens group Gbeing varied, and a distance between the third lens group Gand the fourth lens group Gbeing varied; upon focusing, the fourth lens group Gbeing moved; and a predetermined conditional expression being satisfied. With such a configuration, there is provided a variable magnification optical system whose focusing lens group is compact in size and reduced in weight, so high speed and quiet focusing can be effected without lens barrel being made large in size, and further by which variations in aberrations upon varying magnification from the wide angle end state to the telephoto end state as well as variations in aberrations upon focusing from the infinite distance object to the close distance object can be superbly suppressed.

Variable magnification optical system, optical equipment, imaging equipment and method for manufacturing variable magnification optical system

A zoom optical system includes a plurality of lens groups, and upon zooming distances between adjacent lens groups change. The zoom optical system has a focusing lens group that moves upon focusing and an image-side lens group disposed adjacent to an image side of the focusing lens group. The zoom optical system satisfies the conditional expression 0.000<dL0t/dL1t<1.000, where dL0t denotes a distance on an optical axis between the focusing lens group and the image-side lens group upon focusing on an infinity object in a telephoto end state, and dL1t denotes a distance on the optical axis between the focusing lens group and the image-side lens group upon focusing on a short-distance object in the telephoto end state.

A zoom optical system (ZL) comprises, in order from an object: a first lens group (G) having a positive refractive power; a second lens group (G) having a negative refractive power; a third lens group (G) having a positive refractive power; and a subsequent lens group (GR), wherein upon zooming, a distance between the first lens group (G) and the second lens group (G) changes, a distance between the second lens group (G) and the third lens group (G) changes, and a distance between the third lens group (G) and the subsequent lens group (GR) changes, the subsequent lens group (GR) comprises a focusing lens group that moves upon focusing, and the second lens group (G) comprises a partial group that satisfies following conditional expressions, 1.40&#x3c;fvr/f2&#x3c;2.30, 1.80&#x3c;f1/fw&#x3c;3.50 where fvr: a focal length of the partial group, f2: a focal length of the second lens group (G), f1: a focal length of the first lens group (G), and fw: a focal length of the zoom optical system (ZL) in a wide-angle end state.

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Tokyo, Japan

Kosuke Machida