Nikon Corporation

Konica Minolta Advanced Layers, Inc.

Daicel Polymer Ltd.

Satoru Shibata

Tomoyuki Sashima

Hiroshi Yamamoto

Satoshi Hayakawa

Takeshi Suzuki

Akihiko Obama

Yoshihito Souma

Satoshi Kazahaya

Yuki Kinouchi

Shigeyuki Kosaka

A zoom optical system comprises, in order from an object side: a first lens group having positive refractive power; a front-side lens group; an intermediate lens group having positive refractive power; and a rear-side lens group. The front-side lens group is composed of one or more lens groups and has a negative lens group. At least part of the intermediate lens group is a focusing lens group. The rear-side lens group is composed of one or more lens groups. Upon zooming, the first lens group is moved with respect to an image surface and distances between the first lens group and the front-side lens group, between the front-side lens group and the intermediate lens group, and between the intermediate lens group and the rear-side lens group change. The following conditional expressions are satisfied:−0.750<<4.0002.250<1<5.00032.000≤where fF denotes a focal length of the focusing lens group, fRF denotes a focal length of a lens group closest to the object side in the rear-side lens group, TLW denotes an entire length of the optical system in a wide angle end state, ZD1 denotes a movement amount of the first lens group upon zooming from the wide angle end state to a telephoto end state, and Wω denotes a half angle of view in the wide angle end state.

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

A zoom optical system comprises, in order from an object side: a first lens group having positive refractive power; a front-side lens group; an intermediate lens group having positive refractive power; and a rear-side lens group. The front-side lens group is composed of one or more lens groups and has a negative lens group. At least part of the intermediate lens group is a focusing lens group. The rear-side lens group is composed of one or more lens groups. Upon zooming, distances between the first lens group and the front-side lens group, between the front-side lens group and the intermediate lens group, and between the intermediate lens group and the rear-side lens group change. The following conditional expressions are satisfied:&#x2212;10.000&#x3c;&#x3c;10.0000.010&#x3c;||&#x3c;10.000where fF denotes a focal length of the focusing lens group, fRF denotes a focal length of a lens group closest to the object side in the rear-side lens group, and fXR denotes a focal length of a lens group closet to an image surface in the front-side lens group.

A calculation device calculating an amount of movement in an optical axis direction of a focusing lens which adjusts a focal position of an imaging optical system includes: a first input unit to which first information about a deviation between an imaging surface which captures an image by the imaging optical system and the focal position is repeatedly input; a second input unit to which second information about a shake of the imaging optical system in the optical axis direction is repeatedly input at intervals shorter than those of the first information; and a calculation unit which calculates the amount of movement on the basis of at least one of the first information and the second information, wherein the calculation unit calculates the amount of movement on the basis of the second information between an input of the first information and an input of the next first information.

Calculation device, interchangeable lens, camera body, and imaging device

A variable power optical system (ZL) used for an optical apparatus, such as a camera (), includes, in order from an object: a first lens group (G) having positive refractive power; a second lens group (G) having negative refractive power; a third lens group (G) having positive refractive power; and a fourth lens group (G) having positive refractive power. The distance between the respective lens groups changes upon zooming from the wide-angle end state to the telephoto end state. The third lens group (G) includes: an intermediate group (G) constituted by a positive lens, a negative lens, a negative lens, and a positive lens; and an image side group (G) having negative refractive power and disposed to an image side of the intermediate group (G). Upon focusing, the position of the intermediate group (G) with respect to the image plane is fixed and the image side group (G) moves along the optical axis.

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

A zoom optical system comprises, in order from an object side: a first lens group having positive refractive power; a front-side lens group; an intermediate lens group having positive refractive power; and a rear-side lens group. The front-side lens group is composed of one or more lens groups and has a negative lens group. At least part of the intermediate lens group is a focusing lens group. The rear-side lens group is composed of one or more lens groups. Upon zooming, distances between the first lens group and the front-side lens group, between the front-side lens group and the intermediate lens group, and between the intermediate lens group and the rear-side lens group change. At least one of the following conditional expressions is satisfied:0.010&#x3c;&#x3c;10.0002.250&#x3c;1&#x3c;10.000where fF denotes a focal length of the focusing lens group, fXR denotes a focal length of a lens group closet to the image surface in the front-side lens group, TLW denotes an entire length of the optical system in a wide angle end state, and ZDdenotes a movement amount of the first lens group upon zooming from the wide angle end state to a telephoto end state.

Provided is a variable magnification optical system comprising, in order from an object side along an optical axis, 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 G; upon zooming from a wide angle end state to a telephoto end state, 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 and the fourth lens group being varied; the third lens group Gcomprising, in order from the object side along the optical axis, a 3a-th lens group Ghaving positive refractive power, an aperture S, and a 3b-th lens group Ghaving positive refractive power; a lens group having negative refractive power within the 3b-th lens group Gbeing used as a vibration reduction lens group and moved so as to include a component in a direction orthogonal to the optical axis, whereby image plane correction is performed when image blurring occurs; and predetermined conditions being satisfied. Whereby, a small-size and high-performance variable magnification optical system, capable of realizing a small variation in aberration and attaining a sufficient brightness even in the telephoto state, an imaging apparatus, and a method for manufacturing the variable magnification optical system are provided.

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

A resin-impregnated fiber bundle that can provide a molded article with a high surface impact strength is prepared by impregnating and integrating 100 parts by mass of a bundle of a fiber material (A) with 25 to 300 parts by mass of a thermoplastic resin (B). The fiber bundle has a flattened shape with a lateral cross-sectional shape having a major axis and a minor axis (length of the major axis&#x3e;length of the minor axis). An average length (D1) of the major axis is 0.5 to 2.0 mm. An average flatness ratio (D1/D2), determined from the average length (D1) of the major axis and an average length (D2) of the minor axis, is 1.2 to 8.01. The fiber bundle has a length (L) of 11 to 50 mm, a ratio (L/D1) between L and D1 is 10 to 50, and a bulk density is 0.1 to 0.4 g/cm.

Resin-impregnated fiber bundle, compression molded article, and a method for producing the same

A zoom optical system comprising, in order from an object side: a first lens group (G1) having positive refractive power; a front-side lens group; an intermediate lens group having positive refractive power; and a rear-side lens group. The front-side lens group is composed of one or more lens groups and has a negative lens group. At least part of the intermediate lens group is a focusing lens group. The rear-side lens group is composed of one or more lens groups. Upon zooming, the first lens group and the intermediate lens group are moved with respect to an image surface, a distance between the first lens group and the front-side lens group is changed, and a distance between the intermediate lens group and the rear-side lens group is changed. The following conditional expression is satisfied:0.000&#x3c;&#x3b2;&#x3c;0.800

A first lens group (G) having positive refractive power, a front-side lens group (GX), an intermediate lens group (GM) having positive refractive power, and a rear-side lens group (GR) are arranged in order from an object side. The front-side lens group (GX) is composed of one or more lens groups and has a negative lens group At least part of the intermediate lens group (GM) is a focusing lens group (GF). The rear-side lens group (GR) is composed of one or more lens groups. Upon zooming, the first lens group (G) is moved with respect to an image surface, a distance between the first lens group (G) and the front-side lens group (GX) is changed, a distance between the front-side lens group (GX) and the intermediate lens group (GM) is changed, and a distance between the intermediate lens group (GM) and the rear-side lens group (GR) is changed.

Providing a zoom lens system having excellent optical performance with a high zoom ratio, an imaging apparatus, and a method for zooming the zoom lens system. The system including, in order from an object, a first group Ghaving negative refractive power, a second group Ghaving positive refractive power, a third group Ghaving negative refractive power, and a fourth group Ghaving positive refractive power. An aperture stop S is disposed between the second group Gand the fourth group G. Upon zooming from a wide-angle end state to a telephoto end state, each group is moved such that a distance between the second group Gand the third group Gincreases, a distance between the third group Gand the fourth group Gdecreases, and the aperture stop S is moved together with the third group G. Given conditions are satisfied.

Growing community of inventors

Yokohama, Japan

Satoru Shibata