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:
Jan. 19, 2010
Filed:
Dec. 16, 2008
Tomohiko Ishibashi, Utsunomiya, JP;
Tomohiko Ishibashi, Utsunomiya, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A cemented lens comprises first, second and third optical elements respectively formed by different solid materials, the third and first optical elements being cemented to each other, and the first and the second optical elements being cemented to each other, wherein both an incident surface and an exit surface of the first and second optical elements are refracting surfaces, and the following conditional expressions are satisfied:|Δθ1|>0.0272|Δθ2|>0.0272Δθ1×Δθ2<0φ1×φ<0where ΔθgFand ΔθgFare respectively anomalous dispersion characteristics of the materials for the first and the second optical elements with respect to a g line and an F line, and φand φare respectively refracting powers of the first and second optical elements when both the incident surface and the exit surface of the first and the second optical element are surfaces in contact with air.