Patent ID: 7940472

Claim:
A zoom lens comprising a plurality of lens groups including, in order from an object side: a first lens group having positive refractive power; a second lens group having negative refractive power; a third lens group; and a fourth lens group; the third lens group including, in order from the object side, a first positive lens of the third lens group, a negative lens of the third lens group, and a second positive lens of the third lens group, and the following conditional expressions being satisfied: 1.00 <F 3 /Fw< 3.40 0.700 <D 30 ×N 3133 / Fw< 1.435 where F 3 denotes a focal length of the third lens group, Fw denotes a focal length of the zoom lens in a wide-angle end state, D 30 denotes a thickness of the third lens group, and N 3133 denotes an average refractive index of the first positive lens of the third lens group and the second positive lens of the third lens group.