Tamron Company, Ltd.

Takahiro Mitsuhashi

Takayuki Noda

Toshiya Segawa

Hirofumi Tabata

Minoru Ando

Seigou Nakai

A zoom lens includes a first lens group having a positive refractive power, a second lens group having a negative refractive power, and a rear group having a positive refractive power as a whole in order from an object side. The zoom lens has specific optical characteristics indicated by two expressions.

Zoom lens and imaging apparatus

A zoom lens includes, in order from an object side, a first lens group that is positive, a second lens group that is negative, a third lens group that is positive, and a fourth lens group that is positive. During zooming from a wide angle end to a telephoto end, at least the first lens group and the third lens group are fixed and an interval on an optical axis of an adjacent lens group relative thereto is changed. In the zoom lens, the fourth lens group includes at least one positive lens and satisfies a predetermined conditional expression. In addition, an imaging device includes the zoom lens and an image sensor.

Zoom lens and imaging device

A wide angle zoom lens includes sequentially from the object side, a first lens group having a negative refractive power overall and three lenses, including first to third lenses, having a negative refractive power and disposed farthest on the object side; a second lens group having a positive refractive power overall and one or more sets of cemented lenses; and a third lens group having a negative refractive power. This ultra wide angle zoom lens varies intervals between the first lens group, the second lens group, and the third lens group on the optical axis to zoom from the wide angle end to the telephoto end and satisfies given conditions to thereby enable a high zoom ratio, large diameter, and high resolution.

Wide angle zoom lens

A zoom 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, an aperture stop, a third lens group having a positive refractive power, a fourth lens group having a positive refractive power, and fifth lens group. The zoom lens further satisfies given conditions.

Zoom lens

A zoom 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, an aperture stop, and a third lens group having a positive refractive power. The first lens group includes a negative lens and a positive lens. The second lens group includes sequentially from the object side, a negative lens, a negative lens, and a positive lens. The third lens group includes sequentially from the object side a front group having a positive refractive power, a middle group having a negative refractive power, and a rear group having a positive refractive power. The front group is formed by a positive aspheric lens. The middle group is includes a cemented lens formed by a positive lens and a negative lens.

An imaging lens includes, sequentially from an object side, a first lens (L) configured by a negative meniscus lens disposed with the convex surface on the object side; a second lens (L) configured by a positive biconvex lens; a negative third lens (L); and a fourth lens group (L) configured by a positive meniscus lens disposed with the convex surface on the image plane IMG side. By satisfying given conditions, the imaging lens is able to control ghosting occurring between the last lens surface and the imaging element and ghosting caused by light reflected by the lens surface nearest the object, without sacrifice to the compact-size of the optical system or high optical performance.

Growing community of inventors

Saitama, Japan

Takahiro Mitsuhashi