Method of determining a distribution of fluorescence markers in a sample in which the individual fluorescence markers are located closer to one another than the diffraction barrier, the method comprising: - imaging the sample in an imaging direction onto a detector, wherein a light sensitive detection area of the detector extending transversely to the imaging direction is subdivided into partial areas, - subjecting the sample, out of a subjection direction opposite to the imaging direction, to a light intensity distribution that includes a spatially limited emission area in which the fluorescence markers are induced to emission of fluorescence light, wherein an axial dimension of the emission area along the imaging direction is at least 4-times larger than a lateral extension of the emission area in at least one transvers direction running transversely to the imaging direction, - forming the light intensity distribution in the sample from fluorescence excitation light and fluorescence inhibition light, wherein a partial light intensity distribution of the fluorescence inhibition light narrows the emission area in the at least one transvers direction with regard to an excitation area of a partial light intensity distribution of the fluorescence excitation light to not more than 50 % of a diffraction limited excitation area of a partial light intensity distribution of the fluorescence excitation light, - reading out fluorescence light signals out of the partial areas of the detector for at least one relative position of the emission are with regard to the sample, and - evaluating the fluorescence light signal with regard to the distribution of the fluorescence markers in the sample, characterized in - that a point spread function in imaging the sample in the imaging direction onto the detector is deformed and/or shifted at least in the at least one transvers direction imaged onto the detector depending on a location in the sample along the imaging direction by means of a non-diffractive optical element arranged between the sample and the detector, - wherein, for the at least one relative position of the emission area with regard to the sample, the distribution of the fluorescence markers along the imaging direction is determined under evaluating the fluorescence light signals which are read out of those of the partial areas of the detector that are, in the transvers direction imaged onto the detector, located outside a central area into which all points of the emission area would be imaged in the imaging direction onto the detector each with a minimum diffraction-limited point spread function that is not deformed and/or shifted by means of the non-diffractive optical element. - imaging the sample in an imaging direction onto a detector, wherein a light sensitive detection area of the detector extending transversely to the imaging direction is subdivided into partial areas, - subjecting the sample, out of a subjection direction opposite to the imaging direction, to a light intensity distribution that includes a spatially limited emission area in which the fluorescence markers are induced to emission of fluorescence light, wherein an axial dimension of the emission area along the imaging direction is at least 4-times larger than a lateral extension of the emission area in at least one transvers direction running transversely to the imaging direction, - forming the light intensity distribution in the sample from fluorescence excitation light and fluorescence inhibition light, wherein a partial light intensity distribution of the fluorescence inhibition light narrows the emission area in the at least one transvers direction with regard to an excitation area of a partial light intensity distribution of the fluorescence excitation light to not more than 50 % of a diffraction limited excitation area of a partial light intensity distribution of the fluorescence excitation light, - reading out fluorescence light signals out of the partial areas of the detector for at least one relative position of the emission are with regard to the sample, and - evaluating the fluorescence light signal with regard to the distribution of the fluorescence markers in the sample, - that a point spread function in imaging the sample in the imaging direction onto the detector is deformed and/or shifted at least in the at least one transvers direction imaged onto the detector depending on a location in the sample along the imaging direction by means of a non-diffractive optical element arranged between the sample and the detector, - wherein, for the at least one relative position of the emission area with regard to the sample, the distribution of the fluorescence markers along the imaging direction is determined under evaluating the fluorescence light signals which are read out of those of the partial areas of the detector that are, in the transvers direction imaged onto the detector, located outside a central area into which all points of the emission area would be imaged in the imaging direction onto the detector each with a minimum diffraction-limited point spread function that is not deformed and/or shifted by means of the non-diffractive optical element.