Zoom lens and image pickup apparatus including the same

A zoom lens comprising in order from an object side to an image side:

• a first lens unit having a positive refractive power and configured not to be moved for zooming;
• a second lens group including one or more lens units, having a negative refractive power as a whole, and configured to be moved for zooming;
• an aperture stop;
• a third lens group including one or more lens units, having a positive refractive power as a whole, and configured to be moved for zooming;
• and
• a rear lens unit arranged closest to the image side and configured not to be moved for zooming, wherein
• the first lens unit includes in order from the object side to the image side:
• an 11 sub lens unit having a negative refractive power and configured not to be moved for focusing;
• a 12 sub lens unit having a positive refractive power and configured to be moved for focusing;
• and
• a 13 sub lens unit having a positive refractive power, and
• conditional expressions
• 0.5<f1/fw<4.5;
• and
• 1.1<SPt/SPw<3.0
• are satisfied where f1 represents a focal length of the first lens unit, fw represents a focal length of the zoom lens at a wide angle end, and SPw and SPt respectively represent aperture diameters of the aperture stop at the wide angle end and a telephoto end with respect to an open F-number.

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 a positive refractive power;
• a fourth lens unit having a positive refractive power;
• and
• a fifth lens unit, wherein
• an interval between each pair of adjacent lens units is changed for zooming,
• the zoom lens further comprises an aperture stop between the second lens unit and the third lens unit or between the third lens unit and the fourth lens unit;
• the first lens unit includes:
• an 11 sub lens unit having a negative refractive power and configured not to be moved for focusing;
• a 12 sub lens unit having a positive refractive power and configured to be moved for focusing;
• and
• a 13 sub lens unit having a positive refractive power and configured not to be moved for focusing;
• the 11 sub lens unit includes in order from the object side to the image side:
• a 111 lens having a negative refractive power;
• a 112 lens having a negative refractive power;
• and
• a 113 lens having a positive refractive power,
• conditional expressions
• −0.5<(G112R1+G112R2)/(G112R1−G112R2)<2.0, and
• 0.1<Lsp/L<0.6
• are satisfied where G112R1 represents a curvature radius of a lens surface on the object side of the 112 lens, G112R2 represents a curvature radius of a lens surface on the image side of the 112 lens, Lsp represents a distance on an optical axis from a lens surface closest to the object side to the aperture stop at the wide angle end, and L represents a distance on the optical axis from the lens surface closest to the object side to a lens surface closest to the image side at the wide angle end.

A zoom lens comprising in order from an object side to an image side:

• a first lens unit having a negative refractive power;
• a second lens unit having a positive refractive power;
• a third lens unit having a negative refractive power;
• a fourth lens unit having a positive refractive power;
• a fifth lens unit having a negative refractive power;
• and
• a sixth lens unit having a positive refractive power,
• wherein
• an interval between each adjacent lens units, among the first lens unit, the second lens unit, the third lens unit, the fourth lens unit, the fifth lens unit, and the sixth lens unit, is changed for zooming,
• the first lens unit is configured not to be moved for zooming,
• the first lens unit includes a negative lens at a position closest to the object side, and
• a conditional expression
• 0.5<M4/M2<0.95
• is satisfied where M2 represents a difference between positions of the second lens unit at a wide angle end and a telephoto end in an optical axis direction, M4 represents a difference between positions of the fourth lens unit at the wide angle end and the telephoto end in the optical axis direction, M2 has a positive sign in a case where the second lens unit is moved to the image side for zooming from the wide angle end to the telephoto end, and M4 has a positive sign in a case where the fourth lens unit is moved to the image side for zooming from the wide angle end to the telephoto end.

An image pickup apparatus comprising a zoom lens,

• the zoom lens comprising in order from an object side to an image side:
• a first lens unit configured not to be moved for zooming;
• an Nf lens unit including three or more lenses and having a negative refractive power;
• an aperture stop;
• a first rear lens unit configured to be moved for zooming;
• a second rear lens unit configured to be moved for zooming;
• and
• a third rear lens unit configured not to be moved for zooming, wherein
• the first lens unit includes four or more lenses and includes one or more sub lens units each having a positive refractive power, and
• conditional expressions
• −0.80<Mr2/fr2<0.45;
• −2.0<Mr2/fw<0.3;
• and
• −15.0<Mr1/Mr2<2.0
• are satisfied where Mr1 represents a difference between positions of the first rear lens unit at a wide angle end and a telephoto end in an optical axis direction, Mr2 represents a difference between positions of the second rear lens unit at the wide angle end and the telephoto end in the optical axis direction, fr2 represents a focal length of the second rear lens unit, fw represents a focal length of the zoom lens at the wide angle end, Mr1 has a positive sign in a case where the first rear lens unit is moved to the image side for zooming from the wide angle end to the telephoto end, and Mr2 has a positive sign in a case where the second rear lens unit is moved to the image side for zooming from the wide angle end to the telephoto end.

An image pickup apparatus comprising a zoom lens,

• the zoom lens comprising in order from an object side to an image side:
• a first lens unit having a positive refractive power and configured not to be moved for zooming;
• a second lens group including one or more lens unit, having a negative refractive power as a whole, and configured to be moved for zooming;
• an aperture stop;
• a third lens group including one or more lens units, having a positive refractive power as a whole, and configured to be moved for zooming;
• and
• a rear lens unit arranged closest to the image side and configured not to be moved for zooming, wherein
• the first lens unit includes in order from the object side to the image side:
• an 11 sub lens unit having a negative refractive power and configured not to be moved for focusing;
• a 12 sub lens unit having a positive refractive power and configured to be moved for focusing;
• and
• a 13 sub lens unit having a positive refractive power, and
• conditional expressions
• 0.5<f1/fw<4.5;
• and
• 1.1<SPt/SPw<3.0
• are satisfied where f1 represents a focal length of the first lens unit, fw represents a focal length of the zoom lens at a wide angle end, and SPw and SPt respectively represent aperture diameters of the aperture stop at the wide angle end and a telephoto end with respect to an open F-number.

An image pickup apparatus comprising a zoom lens, the 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 a positive refractive power;
• a fourth lens unit having a positive refractive power;
• and
• a fifth lens unit, wherein
• an interval between each pair of adjacent lens units is changed for zooming,
• the zoom lens further comprises an aperture stop between the second lens unit and the third lens unit or between the third lens unit and the fourth lens unit;
• the first lens unit includes:
• an 11 sub lens unit having a negative refractive power and configured not to be moved for focusing;
• a 12 sub lens unit having a positive refractive power and configured to be moved for focusing;
• and
• a 13 sub lens unit having a positive refractive power and configured not to be moved for focusing;
• the 11 sub lens unit includes in order from the object side to the image side:
• a 111 lens having a negative refractive power;
• a 112 lens having a negative refractive power;
• and
• a 113 lens having a positive refractive power,
• conditional expressions
• −0.5<(G112R1+G112R2)/(G112R1−G112R2)<2.0, and
• 0.1<Lsp/L<0.6
• are satisfied where G112R1 represents a curvature radius of a lens surface on the object side of the 112 lens, G112R2 represents a curvature radius of a lens surface on the image side of the 112 lens, Lsp represents a distance on an optical axis from a lens surface closest to the object side to the aperture stop at the wide angle end, and L represents a distance on the optical axis from the lens surface closest to the object side to a lens surface closest to the image side at the wide angle end.

An image pickup apparatus comprising a zoom lens,

• the zoom lens comprising in order from an object side to an image side:
• a first lens unit having a negative refractive power;
• a second lens unit having a positive refractive power;
• a third lens unit having a negative refractive power;
• a fourth lens unit having a positive refractive power;
• a fifth lens unit having a negative refractive power;
• and
• a sixth lens unit having a positive refractive power,
• wherein
• an interval between each adjacent lens units, among the first lens unit, the second lens unit, the third lens unit, the fourth lens unit, the fifth lens unit, and the sixth lens unit, is changed for zooming,
• the first lens unit is configured not to be moved for zooming,
• the first lens unit includes a negative lens at a position closest to the object side, and
• a conditional expression
• 0.5<M4/M2<0.95
• is satisfied where M2 represents a difference between positions of the second lens unit at a wide angle end and a telephoto end in an optical axis direction, M4 represents a difference between positions of the fourth lens unit at the wide angle end and the telephoto end in the optical axis direction, M2 has a positive sign in a case where the second lens unit is moved to the image side for zooming from the wide angle end to the telephoto end, and M4 has a positive sign in a case where the fourth lens unit is moved to the image side for zooming from the wide angle end to the telephoto end.