US 11,835,698 B2
Zoom lens and image pickup apparatus having the same
Kohei Kimura, Saitama (JP)
Assigned to CANON KABUSHIKI KAISHA, Tokyo (JP)
Filed by CANON KABUSHIKI KAISHA, Tokyo (JP)
Filed on May 4, 2021, as Appl. No. 17/306,983.
Claims priority of application No. 2020-085406 (JP), filed on May 14, 2020.
Prior Publication US 2021/0356722 A1, Nov. 18, 2021
Int. Cl. G02B 15/14 (2006.01); G02B 15/20 (2006.01); G02B 15/177 (2006.01)
CPC G02B 15/144515 (2019.08) [G02B 15/1465 (2019.08); G02B 15/144507 (2019.08); G02B 15/177 (2013.01); G02B 15/20 (2013.01)] 20 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 negative refractive power, a second lens unit having a positive refractive power, and three or more lens units,
wherein a distance between adjacent lens units varies during zooming, and
wherein the following conditional expressions are satisfied:
4.8<m1·f1/skw2<15.0
2.45<β2t/β2w<50.00
where m1 is a moving amount of the first lens unit during zooming from a wide-angle end to a telephoto end, f1 is a focal length of the first lens unit, skw is a backfocus at the wide-angle end, β2t is a lateral magnification of the second lens unit at the telephoto end, and β2w is a lateral magnification of the second lens unit at the wide-angle end.