Patent ID: 8031409

Claim:
An imaging lens, comprising at least a positive lens group, a negative lens group that moves during focusing, a positive lens group that moves toward an object during focusing from infinity to close distance, a negative lens group that is adapted to move so as to have a movement component in a direction substantially vertical to an optical axis, and a positive lens group, which are disposed in order from the object, wherein a condition of a following expression 2.0<(− f 4)/ d 34<20.8 is satisfied, where f4 is a focal length of the negative lens group that is adapted to move in a direction substantially vertical to an optical axis, and d34 is an air distance on the optical axis upon focusing on infinity, between a lens surface disposed closest to the image side of a lens group which is disposed to the object side of the negative lens group that is adapted to move in a direction substantially vertical to the optical axis, and a lens surface disposed closest to the object side of the negative lens group that is adapted to move in a direction substantially vertical to the optical axis.