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

摘要

In a zoom lens system, an optical apparatus, and a manufacturing method, there are provided, in order from an object side: a first lens group having positive power, a second lens group having negative power, a third lens group having positive power, a fourth lens group having negative power, a fifth group having positive power, and an aperture stop disposed to an image side of the second lens group. Upon zooming from a wide-angle end state to a telephoto end state, a distance between the first lens and second lens groups increases, a distance between the second and third lens groups decreases, a distance between the third and fourth lens groups varies, and a distance between the fourth and fifth lens groups varies. With given conditions being satisfied, high optical performance with suppressing variation in aberrations are achieved.

主权项

1. A zoom lens system comprising, in order from an object side along an optical axis:
a first lens group having positive refractive power; a second lens group having negative refractive power; and a third lens group having positive refractive power, upon zooming from a wide-angle end state to a telephoto end state, a distance between the first lens group and the second lens group increasing, a distance between the second lens group and the third lens group decreasing, the third lens group including, in order from the object side along the optical axis, a first sub-lens group having positive refractive power, a second sub-lens group having negative refractive power, and a third sub-lens group, upon zooming from the wide-angle end state to the telephoto end state, a distance between the first sub-lens group and the second sub-lens group varying, and a distance between the second sub-lens group and the third sub-lens group varying, and the first sub-lens group including, in order from the object side along the optical axis, a first positive lens, a second positive lens and a cemented lens, wherein the cemented lens includes, in order from the object side along the optical axis, a third positive lens and a negative lens, wherein the following conditional expression is satisfied:
35.0<νd31−νd34<70.0where νd31 denotes an Abbe number of the first positive lens at d-line, and νd34 denotes an Abbe number of the negative lens at d-line,
wherein the following conditional expression is satisfied:
40.0<νd32−νd34<65.0where νd31 denotes an Abbe number of the second positive lens at d-line, and νd34 denotes the Abbe number of the negative lens at d-line,
wherein the following conditional expression is satisfied:
40.0<νd33−νd34<70.0where νd33 denotes an Abbe number of the third positive lens at d-line, and νd34 denotes the Abbe number of the negative lens at d-line, and
wherein the third positive lens has a biconvex shape and the negative lens has a negative meniscus shape.