Patent ID: 7245442

Claim:
A zoom lens, comprising: four lens groups including a first lens group having a positive refracting power, a second lens group having a negative refracting power, a third lens group having a positive refracting power and a fourth lens group having a positive refracting power, said first, second, third and fourth lens groups being disposed in order from an object side, said second lens group moving, when a lens position state varies from a wide angle end state to a telephoto end state, to an image side while said fourth lens group moves so as to compensate for a variation of an image plane position caused by the movement of said second lens group whereas said first and third lens groups are fixed in the direction of an optical axis; and an aperture stop disposed on the object side of said third lens group; said third lens group including a negative sub group having a negative refracting power and a positive sub group having a positive refracting power and disposed on the image side of said negative sub group with an air distance left therebetween; said positive sub group being shiftable in a direction substantially perpendicular to the optical axis to shift an image in a direction substantially perpendicular to the optical axis; a conditional expression (1) 1.4 <|f 3 n|/f 3<3 (1) being satisfied where f 3 n is the focal distance of said negative sub group disposed in said third lens group and f 3 is the focal distance of said third lens group.