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:
Jun. 04, 2013
Filed:
Sep. 22, 2010
Masaru Sakamoto, Utsunomiya, JP;
Masaru Sakamoto, Utsunomiya, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A zoom lens includes, in order from an object side, a positive first lens unit without moving for zooming, a negative second lens unit for magnification, a positive third lens unit for magnification, a negative fourth lens unit compensating for image plane variation due to magnification, and a positive fifth lens unit without moving for zooming. When assuming a focal length of the entire system at a wide angle end as fW, and a zoom ratio as Z, a focal length fM at an intermediate zoom position is expressed by the equation: fM=fW×√Z. When assuming an interval between the second and third lens units at the wide angle end as LW, and a maximum value of the interval between the second and third lens units in a zoom range from the wide angle end to the focal length fM as Lmax, the following conditional expression is satisfied:1.1<2max/2<55.0.