Abstract: The invention relates to a confocal microscope with a perforated disc arranged in an intermediate plane (perforated disc microscope). A confocal diaphragm is arranged in an intermediate tube which is to be installed on a conventional microscope between the microscope stand and the eyepiece tube. In addition to the movable diaphragm disc, the intermediate tube has an illumination system for confocal microscopy. The reflection of the additional illumination preferably takes place at a dichroic beam splitter. The intermediate tube is thus particularly suitable for confocal fluorescence microscopy. The entering and leaving beam paths of the intermediate tube are telecentric, so that the intermediate tube can also be used in microscopes with objects corrected to infinity focal intercept. The fluorescence wavelength can be varied by means of different dichroic beam splitters in a reflector turret.