Patent ID: 8169720

Claim:
A rear focus wide-angle lens system comprises a first lens group, a diaphragm, and a second lens group, in this order from an object, wherein said second lens group is moved along the optical axis thereof toward the object when focusing is performed from infinity to an object at a closer distance without movement of the first lens group along the optical axis during focusing; and wherein said rear focus wide-angle lens system satisfies the following conditions: 1.5 <F 1/ F 2<3.0 and 0.35 <D 2/ D 1 <0.7 wherein F 1 designates the focal length of said first lens group; F 2 designates the focal length of said second lens group; D 1 designates the distance along the optical axis from the most object-side surface of said first lens group to the most image-side surface thereof; and D 2 designates the distance along the optical axis from the most object-side surface of said second lens group to the most image-side surface thereof.