Abstract: An incident light, bright-field, Kohler illuminating device for a microscope which reflects an illuminating beam into one half of the pupil of a microscope objective, which avoids vignetting of the field of vision without requiring especially short objectives, which can provide illumination with polarized light, and which can be added to any transmitted light microscope including microscopes with revolvable turrets without requiring a specially designed microscope stand.

Abstract: Direct illumination apparatus for microscopes for generating illumination of light fields, phase contrasts, interference contrast and dark fields. A deflecting mirror is located in the observation beam, which is partly specular at its center region and fully specular in an annular zone, and an annular condensor is associated with the illumination system. The apparatus is provided with an adjustable stop or diaphragm for the purpose of suppressing the light field beam and with optical components for illuminating an objective pupil for the light field and the annular condensor with collimated light for the dark field. An aperture stop is located in the path of the light field beam nearly or approximately limiting the illumination of the object field in the path of the dark field beam.

Abstract: An incident light illumination device or instrument for generating dark and light field illumination, wherein at least one optical component is used in a region where the dark field and the light field illumination beams are kept in separate zones. The inner zone is traversed by the light field beam and is endowed with an index of refraction other than the outer zone which is traversed by the dark field beam. A switchable stop for eliminating the light field beam is provided in the vicinity of the optical component (s). The index of refraction of the inner zone of at least one optical component is selected so that the light source is reproduced in the rear focal plane of a microscope objective. A mirror designed as a rotating body and reflecting from its inside surface is located in the optic path from the optic component to the microscope objective and this mirror solely reproduces the dark field beam as a light ring in a plane on the rear side of the microscope objective.