Zoom lens and image capturing apparatus

An image capturing apparatus comprising:

• a zoom lens;
• and
• an image sensor that receives an image formed by the zoom lens,
• wherein the zoom lens includes
• a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, a third lens unit having a positive refractive power, a fourth lens unit having a negative refractive power as an N−1th lens unit, and a fifth lens unit having a negative refractive power as an Nth lens unit, and the lens units being arranged in order from an object side to an image side,
• wherein a distance between adjacent ones of the lens units changes during zooming,
• wherein the N−1th lens unit is arranged second from the image side and the Nth lens unit is arranged closest to the image side among the lens units arranged in the zoom lens,
• wherein the N−1th lens unit and the Nth lens unit are located on the image side with respect to an aperture stop,
• wherein the N−1th lens unit is referred to as an image-side lens unit, and consists of one cemented lens including a positive lens and a negative lens,
• wherein a combined refractive power of lenses from a lens unit having the aperture stop to a lens unit located adjacent to the object side of the image-side lens unit at a wide-angle end when focusing on an object at infinity is a positive refractive power,
• wherein the following inequalities are satisfied:
• 0.4
• <
• fw
• /
• skw
• <
• 2.9
• -
• 8.5
• <
• f
• ⁢
• 1
• /
• f
• ⁢
• 2
• <
• -
• 5.9
• 2.7
• <
• f
• ⁢
• 1
• /
• skw
• <
• -
• 25.
• ,
• and
• -
• 1.27
• <
• fn
• /
• fp
• <
• -
• 0
• .
• 7
• ⁢
• 0
• where fw is a focal length of the zoom lens at the wide-angle end when focusing on an object at infinity, skw is a back focus at the wide-angle end when focusing on an object at infinity, f1 is a focal length of the first lens unit, f2 is a focal length of the second lens unit, fp is a combined focal length of the lenses from a lens unit having the aperture stop to a lens unit located adjacent to the object side of the image-side lens unit at the wide-angle end when focusing on an object at infinity, and fn is a combined focal length of the lenses from the image-side lens unit to the image plane at the wide-angle end when focusing on an object at infinity.

A zoom lens comprising:

• a plurality of lens units, the plurality of lens units consisting of, 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 a positive refractive power, a fourth lens unit having a negative refractive power, and a fifth lens unit having a negative refractive power as an Nth lens unit,
• wherein during zooming, each distance between adjacent lens units changes,
• wherein the fifth lens unit is located on the image side with respect to an aperture stop,
• wherein the fifth lens unit consists of one cemented lens including a positive lens and a negative lens,
• wherein a combined refractive power of the third lens unit having the aperture stop and the fourth lens unit at a wide-angle end when focusing on an object at infinity is a positive refractive power, and
• wherein the following inequalities are satisfied:
• 0.4
• <
• fw
• /
• skw
• <
• 2.9
• -
• 8.5
• <
• f
• ⁢
• 1
• /
• f
• ⁢
• 2
• <
• -
• 5.9
• 2.7
• <
• f
• ⁢
• 1
• /
• skw
• <
• -
• 25.
• ,
• and
• where fw is a focal length of the zoom lens at the wide-angle end when focusing on an object at infinity, skw is a back focus at the wide-angle end when focusing on an object at infinity, f1 is a focal length of the first lens unit, and f2 is a focal length of the second lens unit.