System for confocal illumination of a sample

A system for confocal observation of a sample, comprising:

• a mask which is arranged in both an illumination beam path and in an image beam path and which is rotatable around a central axis, the mask comprising openings arranged in a geometric arrangement in a pinhole plane,
• an arrangement of focusing micro-optics aligned with the geometric arrangement of the openings of the mask so as to focus the illumination light by each of the micro-optics in a focal plane in order to generate a focal pattern there, and
• an optical assembly comprising an objective configured to image the focal pattern onto the sample for generating an illumination pattern moving across the sample and to collect light from the sample by the objective and to image it onto the openings of the mask for confocal filtering,
• wherein the focal plane and the pinhole plane are separated by a distance from each other,
• wherein the optical assembly comprises a path length difference compensation arrangement which is selective with regard to the illumination light and the light collected from the sample so as to compensate for the path length difference between the location of the focal plane of the micro-lenses and the location of the pinhole plane for the light collected from the sample, and
• wherein the mask is transmitting for the illumination light and is non-transmitting for the light collected from the sample.

A system for confocal observation of a sample, comprising:

• a mask which is arranged in both an illumination beam path and in an image beam path and which is rotatable around a central axis, the mask comprising openings arranged in a geometric arrangement in a pinhole plane,
• an arrangement of focusing micro-optics aligned with the geometric arrangement of the openings of the mask so as to focus the illumination light by each of the micro-optics in a focal plane in order to generate a focal pattern there, and
• an optical assembly comprising an objective configured to image the focal pattern onto the sample for generating an illumination pattern moving across the sample and to collect light from the sample by the objective and to image it onto the openings of the mask for confocal filtering,
• wherein the focal plane and the pinhole plane are separated by a distance from each other,
• wherein the optical assembly comprises a path length difference compensation arrangement which is selective with regard to the illumination light and the light collected from the sample so as to compensate for the path length difference between the location of the focal plane of the micro-lenses and the location of the pinhole plane for the light collected from the sample, and
• wherein the micro-optics are located as micro-lenses on a side of the mask which faces the sample with regard to the beam path, wherein the mask is reflecting for the illumination light, and wherein the arrangement is configured to direct the illumination light from the side facing the sample with regard to the beam path to the micro-optics so that the illumination light passes twice through the micro-optics in order to generate the focal pattern.