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:
Apr. 03, 2012
Filed:
May. 25, 2010
Takahiro Yoshimi, Utsunomiya, JP;
Youtarou Sanjou, Utsunomiya, JP;
Takahiro Yoshimi, Utsunomiya, JP;
Youtarou Sanjou, Utsunomiya, JP;
Canon Kabushiki Kaisha, , JP;
Abstract
A zoom lens comprises, 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, and a fourth lens unit having a positive refractive power. The fourth lens unit includes a forty-first lens unit having a negative refractive power and arranged at the object side with reference to the longest air gap and a forty-second lens unit having a positive refractive power and arranged at the image side with reference to the air gap. The forty-first lens unit includes a negative 411st lens, and the forty-second lens unit includes a positive 421st lens. Abbe numbers and partial dispersion ratios of materials of the 411st lens and the 421st lens νd, θgF, νdand θgFare appropriately set.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile