Zoom lens and image pickup apparatus including the same

An image pickup apparatus, comprising:

• a zoom lens, comprising, in order from an object side to an image side:
• a first lens unit having a positive refractive power;
• a second lens unit having a negative refractive power;
• a third lens unit having one of a positive refractive power and a negative refractive power;
• and
• a rear lens group including at least one lens unit,
• wherein the first lens unit is not moved for zooming, and intervals between adjacent lens units are changed during zooming,
• wherein the first lens unit includes at least three lenses, and the second lens unit includes at least three lenses,
• wherein at least two lens surfaces, among lens surfaces of lenses included in the second lens unit except for a lens arranged closest to the object side, have aspherical shapes, and
• wherein the following conditional expressions are satisfied:
• 0.38<|m3/m2|;
• and
• 9.00<ft/fw,
• where fw represents a focal length of the zoom lens at a wide angle end, ft represents a focal length of the zoom lens at a telephoto end, m2 represents a movement amount of the second lens unit during zooming from the wide angle end to the telephoto end, and m3 represents a movement amount of the third lens unit during zooming from the wide angle end to the telephoto end, in which a movement amount has a positive sign when a lens unit is located on the image side at the telephoto end as compared to the wide angle end;
• and
• an image pickup element which receives light of an image formed by the zoom lens.