The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 22, 2022
Filed:
Oct. 02, 2019
Canon Kabushiki Kaisha, Tokyo, JP;
Makoto Nakahara, Utsunomiya, JP;
Takeo Mori, Utsunomiya, JP;
CANON KABUSHIKI KAISHA, Tokyo, JP;
Abstract
The optical system according to the present invention consists of a first lens unit with positive refractive power disposed closest to an object side, a middle group including at least two lens units, and a final lens unit with negative refractive power disposed closest to an image side in which intervals between adjacent lens units are changed during focusing. The middle group includes a first focus lens unit configured to move during focusing, and a second focus lens unit disposed on the image side of the first focus lens unit and configured to move during focusing. An aperture stop is disposed between two lenses included in the middle group. Here, a focal length of the optical system, a focal length of the final lens unit, and a focal length of a second focus lens unit are appropriately determined.