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:
Dec. 14, 1993
Filed:
Oct. 28, 1992
Toshinobu Suzuki, Tokyo, JP;
Olympus Optical Co., Ltd., Tokyo, JP;
Abstract
The invention relates to an objective-with-a-corrector-ring for microscopes that is of about 40 magnifications and has an NA of 0.93 with well-corrected aberrations over an ultra-wide field range, and is less likely to degrade in performance due to a thickness variation of the cover glass. This objective comprises a first lens group G1 that includes a positive meniscus lens concave on the object side and has positive refracting power as a whole, a second lens group G2 that is movable along the optical axis and has small refracting power, a third lens group G3 that is of positive refracting power and converts an exit luminous flux leaving the object and passing through said first and second lens groups to a converging flux, and a fourth lens group G4 that includes two lens surfaces opposite on the concave surfaces to each other through an air separation. The second lens group is movable relative to the first and third lens groups depending on a thickness change of the cover glass.