Patent ID: 7576923

Claim:
A zoom lens comprising: a plurality of lens units each moving independently during a zooming operation including a first lens unit which doesn't move for the zooming operation, is disposed most adjacent to an enlargement side, has a negative refractive power, and composed of two sub-lens units, wherein at least one of said plurality of lens units is moved in the direction of the optical axis thereof during zooming, and wherein the two sub-lens units of said first lens unit includes, in succession from the enlargement side, a 1-1 st lens unit comprising at least one lens having the negative refractive power and configured to be moved during a focusing operation, and a 1-2 nd lens unit having a positive refractive power and configured to be fixed during the focusing operations, wherein the 1-1 st lens unit includes a plurality of lenses having only the negative refractive power.