Patent ID: 9001256
Filing Date: 2015-04-07
Classification: G02B

Abstract:
1. A zoom lens, comprising, in order from an object side: a first lens unit having a positive refractive power which does not move for zooming; a second lens unit having a negative refractive power which moves during zooming; at least one zoom lens unit which moves during zooming; a stop; and an imaging lens unit which does not move for zooming, wherein the first lens unit comprises: wherein the following conditional expressions are satisfied: where f1 is a focal length of the first lens unit, f2 is a focal length of the second lens unit, f11 is a focal length of the first sub lens unit, f12 is a focal length of the second sub lens unit, δ12 is an amount of movement of the second sub lens unit during the focus adjustment from the object at infinity to an object at a minimum distance, and δ13 is an amount of movement of the third sub lens unit during the focus adjustment from the object at infinity to the object at the minimum distance.