Patent ID: 7403339

Claim:
A zoom lens comprising: a first lens unit which is disposed most adjacent to an enlargement side, has negative refractive power, and doesn't move for zooming; a last lens unit disposed most adjacent to a reduction side and having positive refractive power; and one or more lens units moved in the direction of the optical axis thereof during zooming; wherein a first lens in said first lens units which is disposed most adjacent to the enlargement side within said first lens unit, has negative refractive power, the last lens in said last lens units which is disposed most adjacent to the reduction side within said last lens unit, has positive refractive power, and the following condition is satisfied, 32< νdR−νdF, where νdF represents the Abbe number of the material of the first lens and νdR represents the Abbe number of the material of the last lens, wherein the following condition is satisfied, ν dR−νdF< 50.