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:
Mar. 26, 1996
Filed:
Nov. 19, 1993
Toshinobu Suzuki, Tokyo, JP;
Olympus Optical Co., Ltd., Tokyo, JP;
Abstract
An apochromat-class immersion microscope objective having a magnification of about 40, a NA of about 1.0, and a satisfactorily flattened image field. The microscope objective includes a first lens unit G1 of positive refractive power which has a cemented lens composed of a plano-convex lens and a meniscus lens having a strong concave surface directed toward the object side, a second lens unit G2 having a cemented lens composed of three lens elements, that is, negative, positive and negative lenses, a third lens unit G3 having a cemented lens, a fourth lens unit G4 including a cemented meniscus lens having a strong concave surface directed toward the image side, and a fifth lens unit G5 including a cemented meniscus lens composed of a negative lens and a positive lens and having a strong concave surface directed toward the object side. The microscope objective satisfies conditions concerning the refractive index difference between the first and fifth lens units, the focal lengths of the first and fourth lens units, and the back focus of the entire system.