Liquid immersion microscope objective

Abstract

The invention is directed to an immersion microscope objective. This microscope objective contains four lens groups. The first lens group has a focal length of 2.6f–3.1f, where f is the total focal length of the microscope objective. The first lens group contains two lens components with a collecting effect. The first lens component has a focal length of 3f–4.5f. One of the lenses in the first lens component is made from a material with n greater than 1.72. A lens of the second lens component is made from a material with a partial dispersion of a first type. The second lens group with a focal length of 8f–10.2f comprises at least two lenses which are cemented together. A collecting lens is made from a material with a partial dispersion of the first type, and a diverging lens is made from a material with a partial dispersion of a second type. There follows a third lens group with a focal length greater than |25f|. The third lens group-times contains at least two lenses which are cemented together, one of which is a collecting lens made from a material with a fluor crown anomaly. Finally, there follows a fourth lens group with a focal length greater than |6⅔f| and comprising two meniscus-shaped lenses whose hollow surfaces face one another.