Patent ID: 8228616

Claim:
A zoom lens comprising, in order from the object side to the image side: a first lens group having positive refractive power, the first lens group consisting of, in order from the object side to the image side, a negative lens, a biconvex positive lens, a positive lens having a convex surface on the object side, and a meniscus positive lens having a convex surface on the object side; a second lens group having negative refractive power, the second lens group consisting of, in order from the object side to the image side, three negative lenses and one positive lens; a third lens group having positive refractive power, the third lens group including a lens having aspherical surfaces on both sides; and a fourth lens group having positive refractive power, the fourth lens group consisting of, in order from the object side to the image side, a biconvex positive lens having aspherical surfaces on both sides and a cemented lens composed of a meniscus negative lens having a concave surface on the image side and a positive lens having a convex surface on the object side, wherein at least the second and fourth lens groups are moved along the optical axis during zooming.