US 12,013,520 B2
Zoom lens and image pickup apparatus
Tomoya Yamada, Tochigi (JP); Masaru Sakamoto, Tochigi (JP); Yu Inomoto, Saitama (JP); and Naotoshi Ogawa, Tochigi (JP)
Assigned to CANON KABUSHIKI KAISHA, Tokyo (JP)
Filed by CANON KABUSHIKI KAISHA, Tokyo (JP)
Filed on Jun. 23, 2021, as Appl. No. 17/355,730.
Claims priority of application No. 2020-111195 (JP), filed on Jun. 29, 2020.
Prior Publication US 2021/0405336 A1, Dec. 30, 2021
Int. Cl. G02B 15/14 (2006.01); G02B 15/20 (2006.01); G02B 27/00 (2006.01)
CPC G02B 15/1461 (2019.08) [G02B 15/1441 (2019.08); G02B 15/145119 (2019.08); G02B 15/145125 (2019.08); G02B 15/145129 (2019.08); G02B 15/20 (2013.01); G02B 27/0025 (2013.01)] 19 Claims
OG exemplary drawing
 
1. 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 move for zooming;
two or more intermediate lens units configured to move in zooming; and
a rear lens unit having a positive refractive power,
wherein an interval between each pair of adjacent lens units changes in zooming,
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 and configured not to move for focusing, a second lens subunit having a positive refractive power and configured to move for focusing, and a third lens subunit having a positive refractive power, and
wherein the zoom lens satisfies following inequalities:
1.655≤(f1+bok1)/f1≤3.000, and
2.370≤ft/f1≤3.145,
1.30≤Fnow≤3.50,
where f1 denotes a focal length of the first lens unit, bok1 denotes a length on an optical axis from a last surface of the first lens unit to a rear principal point of the first lens unit, and ft denotes a focal length of the zoom lens at a telephoto end, and Fnow denotes an F-number of the zoom lens at a wide-angle end.