Immersion objective lens for a microscope

US10732395B2 · kind B2 · utility

Assignee

• LEICA MICROSYSTEMS CMS GMBH · DE

Inventors

• Christian Schulz · Duisburg, DE
• Christian Schumann · Gießen, DE

Key dates

• Filing date: Apr 19, 2018
• Grant date: Aug 4, 2020
• Expiry date: Apr 19, 2038

Classification

• Technology area (CPC G): Physics
• CPC primary: G02B27/0037
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

An immersion objective lens for a microscope includes a first lens group having positive refractive power, a second lens group having positive refractive power, a third lens group having negative refractive power and a fourth lens group having positive refractive power disposed in this sequence from the object side. The second lens group is moveable along an optical axis so as to achieve a corrective effect with respect to a spherical aberration, such that a sum of a distance between the second lens group and the first lens group and of a distance between the second lens group and the third lens group is constant. The corrective effect of the second lens group is predetermined such that the spherical aberration is minimized for a light incidence that corresponds to a mean numerical aperture that lies between zero and a nominal aperture of the immersion objective lens.