Patent ID: 8498058

Claim:
A zoom lens comprising: 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 positive refractive power, wherein the first through fourth lens groups are sequentially arranged from an object side to an image side, when zooming is performed from a wide angle position to a telephoto position, the distance between the first lens group and the second lens group increases, the distance between the second lens group and the third lens group decreases, and the distance between the third lens group and the fourth lens group increases, the second lens group comprises a first lens, a second lens, and a third lens, and the second lens group satisfies 1.45≦N (2-2) ≦1.65, and 1.45≦N (2-3) ≦1.65, where N (2-2) is the refractive index of the second lens of the second lens group, and N (2-3) is the refractive index of the third lens of the second lens group.