Patent ID: 11899191
Assignee: CANON KABUSHIKI KAISHA
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 0:
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 plurality of zooming lens units configured to move along an optical axis in zooming and including a lens unit having a negative refractive power; and
a final lens unit having a positive refractive power,
wherein a distance between each pair of adjacent lens units changes in zooming,
wherein the zoom lens comprises a diaphragm configured to move along the optical axis in zooming,
wherein the first lens unit includes, in order from the object side to the image side, a first subunit having a negative refractive power, a second subunit having a negative refractive power, and at least one subsequent subunit, a distance between each pair of adjacent subunits changing for focusing,
wherein the second subunit is configured to move along the optical axis for focusing, and
wherein the following inequality is satisfied:

0.20<f1R/f1<1.10; and

−0.60<β12/β1R<0.00, where f1R is a focal length of the at least one subsequent subunit in an in-focus state at infinity, f1 is a focal length of the first lens unit in the in-focus state at infinity, β12 is a lateral magnification of the second subunit in the in-focus state at infinity, and β1R is a lateral magnification of the at least one subsequent subunit in the in-focus state at infinity.