Zoom lens and image pickup apparatus

An image pickup apparatus comprising a zoom lens, and

• an image pickup element for picking up an image formed by the zoom lens,
• wherein the zoom lens comprises in order from an object side to an image side, a first lens unit having a positive refractive power that does not move for zooming, three or more intermediate lens units that move during zooming, and a rear lens unit having a positive refractive power,
• wherein each interval between adjacent lens units changes during zooming,
• wherein the zoom lens includes an aperture stop in the rear lens unit, in a lens unit arranged adjacent to the rear lens unit, or between the lens unit arranged adjacent to the rear lens unit and the rear lens unit,
• wherein the first lens unit includes in order from the object side to the image side, a first lens subunit having a negative refractive power that does not move for focusing, a second lens subunit having a positive refractive power that moves for focusing, and a third lens subunit having a positive refractive power,
• wherein following inequalities are satisfied,
• 1.700≤(f1+bok1)/f1≤2.200
• 1.50≤f1/fw≤4.00
• 7.1≤ft/fw≤10.0
• where f1 represents a focal length of the first lens unit, bok1 represents a length on an optical axis from a surface arranged at a most image-side of the first lens unit to a rear principal point of the first lens unit, fw represents a focal length of the zoom lens at a wide angle end, and ft represents a focal length of the zoom lens at a telephoto end.