Patent ID: 8743469

Claim:
A zoom lens, comprising, in order from an object side to an image 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; a third lens unit having a negative refractive power which moves during zooming; a fourth lens unit having a positive refractive power which moves during zooming; and a fifth lens unit having a positive refractive power which does not move for zooming, wherein the following conditions are satisfied: 5 <L 2 w/L 2 t< 50; 0.6 <L 2 w/L 3 w< 2.5; and 10<| f 1 /f 23 w|< 25, where L 2 w and L 2 t represent air intervals between the second lens unit and the third lens unit at a wide-angle end and at a telephoto end, respectively, L 3 w represents an air interval between the third lens unit and the fourth lens unit at the wide-angle end, f 1 represents a focal length of the first lens unit, and f 23 w represents a combined focal length of the second lens unit and the third lens unit at the wide-angle end.