Patent ID: 7830613

Claim:
A zoom lens, comprising, in order from an object side toward an image side thereof, a first lens group having positive refracting power, a second lens group having negative refracting power, a third lens group having positive refracting power, and a fourth lens group having positive refracting power, wherein: said zoom lens further comprises an aperture stop located on an image side with respect to said second lens group and on an object side with respect to a lens surface located in said third lens group and nearest to the image side; upon zooming from a wide-angle end to a telephoto end, a space between said first lens group and said second lens group grows wide, a space between said second lens group and said third lens group becomes narrow, and a space between said third lens group and said fourth lens group changes; said first lens group comprises a positive lens and a negative lens; a total number of lenses in said first lens group is 2; said second lens group consists of, in order from the object side, a front unit of negative refracting power and a rear unit of positive refracting power; said third lens group consists of, in order from the object side, a front unit of positive refracting power and a rear unit of negative refracting power; said fourth lens group comprises a positive lens component; a total number of lens components in said fourth lens group is 1; said front unit of said second lens group comprises a negative lens component; a total number of lens components in the front unit of said second lens group is 1; said rear unit of said second lens group comprises, in order from the object side toward the image side, a negative lens and a positive lens; a total number of lenses in the rear unit of said second lens group is 2; and said negative lens component in the front unit of said second lens group and said negative lens in the rear unit of said second lens group satisfy the following condition (1A): 2.9 <f 2GN2 /f 2GN1 <30 (1A) where f 2GN1 is a focal length of said negative lens component in the front unit of said second lens group, and f 2GN2 is a focal length of said negative lens in the rear unit of said second lens group.