Abstract: An optical microscope can be converted by the user quickly with a few movements of the hand so that it can be used as an upright variant or as an inverted variant. The required optical elements are accommodated in components that can be mechanically separated from one another and variously combined. The optical system is calculated in such a way that an upright microscope with vertical illumination or transmitted illumination or an inverted microscope with vertical illumination or transmitted illumination results when the components are combined in the required manner by interfaces provided for this purpose.

Abstract: A transmitted-light illumination arrangement for microscopes has at least one LED which is arranged interchangeably in or in the vicinity of the plane of the aperture diaphragm of illumination optics or in front of Köhler illumination optics. The transmitted-light illumination arrangement advantageously has at least one LED light source radiating in the illumination direction of the microscope and at least one LED light source radiating in the opposite direction, wherein the light of the oppositely radiating light source is deflected in the illumination direction via deflecting mirrors, preferably a concave mirror, this light source being located in the focal point thereof.

Abstract: A transmitted-light illumination arrangement for microscopes has at least one LED which is arranged interchangeably in or in the vicinity of the plane of the aperture diaphragm of illumination optics or in front of Köhler illumination optics. The transmitted-light illumination arrangement advantageously has at least one LED light source radiating in the illumination direction of the microscope and at least one LED light source radiating in the opposite direction, wherein the light of the oppositely radiating light source is deflected in the illumination direction via deflecting mirrors, preferably a concave mirror, this light source being located in the focal point thereof.

Abstract: A transmitted-light illumination arrangement for microscopes has at least one LED which is arranged interchangeably in or in the vicinity of the plane of the aperture diaphragm of illumination optics or in front of Köhler illumination optics. The transmitted-light illumination arrangement advantageously has at least one LED light source radiating in the illumination direction of the microscope and at least one LED light source radiating in the opposite direction, wherein the light of the oppositely radiating light source is deflected in the illumination direction via deflecting mirrors, preferably a concave mirror, this light source being located in the focal point thereof.