Microscope optical system and microscope objective lens

Abstract

A microscope optical system comprises an objective lens and an intermediate magnification varying part disposed just after the image side of the objective lens. A microscope objective lens according to another aspect of the invention comprises a first lens group and a second lens group in the mentioned order from the object side. The first lens group includes a positive meniscus lens with the concave surface facing the object side and one or more cemented lenses, the first lens group having a positive refractive power as a whole, at least one of the cemented lenses includes a lens made of a material having an Abbe's number equal to or larger than 80, and conditions 0.3≦wd/f≦0.45 and 0.6≦NA are satisfied, where f represents the focal length of the microscope objective lens as a whole, wd represents the working distance of the microscope objective lens, and NA represents the numerical aperture of the microscope objective lens.

Dependencies are inferred from the claim text.