Patent ID: 7286299

Claim:
A zoom lens sequentially comprising, along an optical axis from an object to be imaged: a first lens group which has positive refracting power and is always fixed at a position in an optical axis direction in zooming and focusing; 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, said fourth lens group sequentially comprising a positive lens, negative lens, and positive lens along the optical axis from the object to be imaged; wherein zooming is performed by moving at least said second lens group and said fourth lens group, focusing is performed by moving at least said fourth lens group, and said first lens group includes an optical element having an effect of bending an optical path of a light beam and satisfies the following conditional expression: 2.0 <f 1 /fw< 4.5 where f 1 is a focal length of said first lens group and fw is a focal length of said zoom lens at a wide-angle end.