Zoom lens, imaging apparatus, and method for manufacturing zoom lens

摘要

A zoom lens including, from an object: a front group having negative power; and a rear group having positive power, the rear group including, from the object, a positive lens, a negative lens having a concave surface facing the object, a cemented positive lens constructed by a negative lens and a positive lens, and a cemented lens constructed by a positive lens and a negative lens, the rear group further including a focusing group disposed to the object side of the positive lens La for focusing from infinity to a close object by moving from the object side to an image side, a distance between the front group and the rear group being varied thereby zooming from a wide-angle end state to a telephoto end state, and given condition being satisfied, thereby providing a downsized zoom lens having wide angle of view and excellent optical performance with fewer lenses.

主权项

1. A zoom lens comprising, in order from an object side:
a front lens group having negative refractive power; and a rear lens group having positive refractive power, the front lens group including, in order from the object side, an aspherical lens component Ga that has negative refractive power and a shape that the negative refractive power becomes smaller toward the periphery, and an aspherical lens component Gb that has positive refractive power and a shape that the positive refractive power turns to negative refractive power toward the periphery or has negative refractive power and a shape that the negative refractive becomes stronger toward the periphery, a distance between the front lens group and the rear lens group being varied thereby carrying out zooming from a wide-angle end state to a telephoto end state, the following conditional expression being satisfied:
0.0406≦(−Fa)/|Fb|<0.650 where Fa denotes a focal length of the aspherical lens component Ga in the front lens group, and Fb denotes a focal length of the aspherical lens component Gb in the front lens group.