US 11,703,669 B2
Zoom lens and image pickup apparatus
Kenta Sudo, Tochigi (JP); and Kazuki Someya, Tochigi (JP)
Assigned to CANON KABUSHIKI KAISHA, Tokyo (JP)
Filed by CANON KABUSHIKI KAISHA, Tokyo (JP)
Filed on Dec. 18, 2020, as Appl. No. 17/126,458.
Claims priority of application No. 2019-233783 (JP), filed on Dec. 25, 2019; and application No. 2019-234095 (JP), filed on Dec. 25, 2019.
Prior Publication US 2021/0199937 A1, Jul. 1, 2021
Int. Cl. G02B 15/14 (2006.01); G02B 15/16 (2006.01)
CPC G02B 15/1441 (2019.08) [G02B 15/144113 (2019.08); G02B 15/145121 (2019.08); G02B 15/16 (2013.01)] 8 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;
a second lens unit having a negative refractive power;
a third lens unit having a positive refractive power; and
one or more rear lens units,
wherein the first lens unit does not move for zooming,
an interval between each pair of adjacent lens units changes in zooming,
the first lens unit includes four positive lenses including a positive lens made of material with an Abbe number less than 30, and
following conditional expressions are satisfied:
0.05<TL1/f1<0.80,
40<ft/fw<200, and
0.2<TL/ft<0.7,
where TL1 represents a distance on an optical axis from a surface of the first lens unit closest to the object side to a surface of the first lens unit closest to the image side, f1 represents a focal length of the first lens unit, ft represents a focal length of the zoom lens at a telephoto end, fw represents a focal length of the zoom lens at a wide-angle end, and TL represents a total length of the zoom lens at the telephoto end.