Artefact reduction for angularly-selective illumination

An optical device, comprising:

• a sample holder configured to fix an object in the beam path of the optical device;
• an illumination module having a plurality of light sources and configured to illuminate the object from a plurality of illumination directions by operating the light sources;
• a detector arranged in the beam path of the optical device;
• and
• a computing unit configured to control the illumination module for illuminating an object from a plurality of measurement illumination directions;
• wherein the computing unit is configured to control the detector for capturing measurement images of the object, wherein the measurement images are assigned to the measurement illumination directions,
• wherein the computing unit is configured, for each measurement image, to carry out an artefact reduction which reduces an artefact in the respective measurement image on account of a contaminant arranged in defocused fashion, and
• wherein the computing unit is configured, after carrying out the artefact reduction for all the measurement images, to combine the measurement images in order to obtain a result image.

An optical device, comprising:

• a sample holder configured to fix an object in the beam path of the optical device;
• an illumination module having a plurality of light sources and configured to illuminate the object from a plurality of illumination directions by operating the light sources, wherein each illumination direction has an assigned luminous field;
• and
• a filter arranged between the illumination module and the sample holder and configured to expand the assigned luminous field for each illumination direction.