Device for distributing linearly polarised illumination light and detection light in a microscope; comprising a distribution optical unit, which guides the linearly polarised illumination light onto a sample and guides the detection light emanating from the sample onto at least one detector; wherein the distribution optical unit comprises: a polarisation unit (28, 30, 32) arranged in a first light path for converting the illumination light directed onto the sample into a first polarisation state; a beam splitter arranged in the first light path and having a polarisation dependence in such a way that it guides the illumination light that has been converted into the first polarisation state onto the sample and guides a first portion of the detection light emanating from the sample, said first portion having the first polarisation state, back into the first light path, while it guides a second portion of the detection light, said second portion having a second polarisation state, which is different from the first polarisation state, into a second light path separated from the first light path; and a beam combiner, which combines the first portion and the second portion of the detection light with one another and guides the latter onto the detector, wherein the polarisation unit (28, 30, 32) has a Faraday rotator, which rotates the direction of polarisation of the illumination light by a first angle magnitude in a predetermined direction of rotation and which rotates the direction of polarisation of the first portion of the detection light, said first portion having been guided back into the first light path, by the same first angle magnitude in the same direction of rotation, and a retardation plate, which rotates the direction of polarisation of the illumination light that has passed through the Faraday rotator by a second angle magnitude in the predetermined direction of rotation and which rotates the direction of polarisation of the linearly polarised first portion of the detection light, said first portion having been guided back into the first light path, before passage through the Faraday rotator, by the same second angle magnitude in the opposite direction of rotation, characterized in that the polarisation unit (28, 30, 32) has a polarising light entrance element, which guides the illumination light emitted by a light source onto the Faraday rotator and guides the portion of the detection light that has passed through the Faraday rotator onto the beam combiner, wherein a Faraday rotator and a retardation plate are arranged only in the first of the two light paths. a polarisation unit (28, 30, 32) arranged in a first light path for converting the illumination light directed onto the sample into a first polarisation state; a beam splitter arranged in the first light path and having a polarisation dependence in such a way that it guides the illumination light that has been converted into the first polarisation state onto the sample and guides a first portion of the detection light emanating from the sample, said first portion having the first polarisation state, back into the first light path, while it guides a second portion of the detection light, said second portion having a second polarisation state, which is different from the first polarisation state, into a second light path separated from the first light path; and a beam combiner, which combines the first portion and the second portion of the detection light with one another and guides the latter onto the detector, wherein the polarisation unit (28, 30, 32) has a Faraday rotator, which rotates the direction of polarisation of the illumination light by a first angle magnitude in a predetermined direction of rotation and which rotates the direction of polarisation of the first portion of the detection light, said first portion having been guided back into the first light path, by the same first angle magnitude in the same direction of rotation, and a retardation plate, which rotates the direction of polarisation of the illumination light that has passed through the Faraday rotator by a second angle magnitude in the predetermined direction of rotation and which rotates the direction of polarisation of the linearly polarised first portion of the detection light, said first portion having been guided back into the first light path, before passage through the Faraday rotator, by the same second angle magnitude in the opposite direction of rotation, characterized in that the polarisation unit (28, 30, 32) has a polarising light entrance element, which guides the illumination light emitted by a light source onto the Faraday rotator and guides the portion of the detection light that has passed through the Faraday rotator onto the beam combiner, wherein a Faraday rotator and a retardation plate are arranged only in the first of the two light paths.