Tamron Company, Ltd.

Sony Corporation

Kazuya Watanabe

Hiroki Yamano

So Miyasaka

Yoshito Iwasawa

Masafumi Sueyoshi

Daisuke Kuroda

Wataru Kusaka

Hiromitsu Sakuraba

Hisashi Sutoh

The present invention provides a zoom lens which is the zoom lens that includes a first lens group G1 having positive refractive power, a second lens group G2 having negative refractive power, and a third lens group G3 having positive refractive power in order from an object side, and changes focal length by changing an air interval between the respective lens groups, the zoom lens including a focus group F constituted from one lens in or after the third lens group G3, moving only the focus group F along an optical axis direction when focusing from an infinity object to a proximity object, and satisfying specific conditional expressions, and an imaging apparatus including the zoom lens.

Zoom lens and imaging apparatus

An imaging lens includes, sequentially from an object side, a first lens group having a positive refractive power; a second lens group having a negative refractive power; a third lens group having a positive refractive power; and a fourth lens group having a negative refractive power. The third lens group is configured by a single lens element, and is moved along an optical axis, whereby focusing is performed.

Imaging lens

A retractable zoom lens includes sequentially from an object side, a first lens group having positive refractive power, a second lens group having negative refractive power, a third lens group having positive refractive power, and a fourth lens group having positive refractive power. The third lens group includes sequentially from the object side, a first lens that is a positive lens, a second lens that is a positive lens, and a third lens that is a negative lens. The retractable zoom lens performs variable magnification by independently moving the respective lens groups along the optical axis. Further, the retractable zoom lens satisfies given conditions and maintains high optical performance while enabling a wider angle and a reduction of overall length.

Retractable zoom lens

The positioning of the first through the third lenses in the optical axis direction is performed in the state that the optical axes are aligned by press-fitting the outer circumference surfaces of the first through the third lenses of the second lens group respectively to the first through the third lens holding portions of the lens frame and the state that the first reference plane of the first lens and the second reference plane of the second lens are contacted and the third reference plane of the second lens and the fourth reference plane of the third lens are contacted.

Lens barrel and imaging apparatus

The bent zoom lens is configured to include, arranged in order from an object side, a first lens group GRhaving a positive refractive power, a second lens group GRhaving a negative refractive power, a third lens group GRhaving a positive refractive power, a fourth lens group GRhaving a negative refractive power, and a fifth lens group GRhaving a positive refractive power. The first lens group GRincludes a single piece of meniscus lens having a negative refractive power and having a convex surface directed toward an object side, a prism that bends an optical path, and a single piece of double-convex lens having a positive refractive power.

Bent zoom lens

There is provided a zoom lens system including at least a first lens group GRhaving a positive refractive power, a second lens group GRhaving a negative refractive power, a third lens group GRhaving a positive refractive power, a fourth lens group GRhaving a negative refractive power, a fifth lens group GRhaving a positive refractive power, and a sixth lens group GRhaving a negative refractive power, arranged sequentially from the object side. Zoom ratio is varied by changing the distance between the adjacent lens groups. The distance, taken as DW(i-j), between the i- and j-th lens groups at the wide angle end during at-infinity imaging and that, taken as DT(i-j), between the i- and j-th lens groups at the telephoto end during at-infinity imaging meet the following conditions (1), (2), (3), (4) and (5)DW(1-2)&#x3c;DT(1-2)&#x2003;&#x2003;(1)DW(2-3)&#x3e;DT(2-3)&#x2003;&#x2003;(2)DW(3-4)&#x3e;DT(3-4)&#x2003;&#x2003;(3)DW(4-5)&#x3c;DT(4-5)&#x2003;&#x2003;(4)DW(5-6)&#x3c;DT(5-6)&#x2003;&#x2003;(5)and focusing is made by moving the fourth lens group GRaxially of the lenses.

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Saitama, Japan

Kazuya Watanabe