Patent ID: 7177100

Claim:
A zoom lens comprising: a first lens group having a negative refractive power; a second lens group having a positive refractive power; and a third lens group having a positive refractive power in this order from an object side, wherein the zoom lens varies a magnification thereof by changing distances among the first, second and third lens groups, the first lens group comprises: a first lens that has a negative refractive power and has a meniscus shape directing a convex surface on the object side; a second lens that has a negative refractive power and has a meniscus shape directing a convex surface on the object side; and a third lens that has a positive refractive power and has a meniscus shape directing a convex surface on the object side, wherein the first, second and third lenses are arranged in this order from the object side, the second lens group comprises: a fourth lens having a bi-convex shape; a fifth lens having a bi-concave shape; and a sixth lens having a meniscus shape directing a concave surface on the object side, wherein the fourth, fifth and sixth lenses are arranged in this order from the object side, and the fourth and fifth lenses comprises a cemented lens in which lens surfaces of the fourth and fifth lenses are cemented with each other, the third lens group consists of a positive lens, and each of the first and second lens groups has at least one aspherical surface.