Abstract: To provide an immersion microscope objective lens capable of making a numerical aperture NA larger than 1.45 even if an ordinary oil is used, the objective lens includes, in order from an object, a first lens group, a second lens group, and a third lens group. The first lens group includes a first cemented lens constructed by a plano-convex lens having a plane surface facing to the object cemented with a meniscus lens having a convex surface facing to an image, and two or more cemented positive lenses disposed to the image side of the first cemented lens. The second lens group includes one or more cemented lens. The third lens group includes, in order from the object, a cemented meniscus lens having a strong concave surface facing to the image, and a cemented meniscus lens having a strong concave surface facing to the object. Given conditional expressions are satisfied.

Abstract: To provide an immersion microscope objective lens capable of making a numerical aperture NA larger than 1.45 even if an ordinary oil is used, the objective lens includes, in order from an object, a first lens group, a second lens group, and a third lens group. The first lens group includes a first cemented lens constructed by a plano-convex lens having a plane surface facing to the object cemented with a meniscus lens having a convex surface facing to an image, and two or more cemented positive lenses disposed to the image side of the first cemented lens. The second lens group includes one or more cemented lens. The third lens group includes, in order from the object, a cemented meniscus lens having a strong concave surface facing to the image, and a cemented meniscus lens having a strong concave surface facing to the object. Given conditional expressions are satisfied.