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:
Nov. 30, 2010
Filed:
Jun. 20, 2007
Daisuke Koreeda, Saitama, JP;
Shuichi Takeuchi, Saitama, JP;
Daisuke Koreeda, Saitama, JP;
Shuichi Takeuchi, Saitama, JP;
Hoya Corporation, Tokyo, JP;
Abstract
There is provided an objective lens including a first optical member and a second optical member which are made of materials different from each other and are cemented together at a cementing surface. The cementing surface includes a first phase shift structure having a plurality of refractive surface zones concentrically formed about an optical axis of the objective lens. The first phase shift structure satisfies conditions (1) and (2):0.85<Φ2/Φ1<1.15  (1)0.10<|(Φ3−Φ2)/Φ1|<0.50  (2) where Φ1=m(λ)×(λ/(n2(λ)−n1(λ))), Φ2=m(λ)×(λ/(n2(λ)−n1(λ))), Φ3=m(λ)×(λ/(n2(λ)−n1(λ))), m(λ), m(λ), and m(λ) are diffraction orders at which diffraction efficiencies of the first through third light beams are maximized, respectively, n1 (λ), n1 (λ), and n1 (λ) are refractive indexes of the first optical member, respectively, and n2 (λ), n2 (λ), and n2 (λ) are refractive indexes of the second optical member, respectively.